Autor Wątek: [AS]SpaceX Readies First Batch of Starlink Satellites for Wednesday Night Launch  (Przeczytany 3885 razy)

0 użytkowników i 1 Gość przegląda ten wątek.

Online Orionid

  • Weteran
  • *****
  • Wiadomości: 14825
  • Very easy - Harrison Schmitt
SpaceX Readies First Batch of Starlink Satellites for Wednesday Night Launch
By Ben Evans, on May 14th, 2019


On its sixth launch of 2019, Wednesday’s planned night launch of the first members of Starlink will also be SpaceX’s fourth flight of the year executed in the hours of darkness. Photo Credit: John Studwell / AmericaSpace

If you believe Elon Musk, the first baby-steps on the journey to Mars begin late Wednesday evening from Space Launch Complex (SLC)-40 at Cape Canaveral Air Force Station, Fla. The SpaceX CEO has made no secret of the fact that he intends to transform humanity into a spacefaring civilization—with the fabrication of a permanently-inhabited base on the Red Planet his ultimate personal goal—and expects part of the financial base for that endeavor to come from the Starlink flotilla of low-Earth-orbiting internet communications satellites.

When the next Upgraded Falcon 9 lights up the night sky along the Space Coast on Wednesday, it will deliver 60 of these smallsat-class satellites into space to begin what Mr. Musk expects will revolutionize low-cost broadband internet provision. In Twitter comments provided late Saturday, the SpaceX CEO noted that the five-dozen-strong swarm of satellites were “flat-packed” into the booster’s payload fairing, with no dispenser.



The Upgraded Falcon 9, bearing the Paz payload fairing, is raised to the vertical for launch in February 2018. This mission included a pair of Starlink demo satellites, later dubbed “Tintin A” and “Tintin B”. Photo Credit: SpaceX/Twitter

Current plans are for the Block 5 core to rise from SLC-40 during a 90-minute “launch window”, extending from 10:30 p.m. through midnight EDT Wednesday, 15 May. Weather conditions were predicted to be 70/80-percent favorable and the customary Static Fire Test of the nine Merlin 1D+ first-stage engines was performed on Monday, 13 May.

If the mission launches on time, it will occur a few hours shy of 12 days since another Upgraded Falcon boosted the CRS-17 Dragon from the same launch pad, en-route to the International Space Station (ISS). This will mark the shortest interval yet achieved by SpaceX in executing flights from SLC-40, slightly pipping the 13 days which elapsed between the launches of the CRS-6 Dragon and the heavyweight TurkmenÄlem52E/MonacoSat communications satellite, way back in April 2015.

Should the mission fly on time, it will also eclipse SpaceX’s all-time record between launches achieved from neighboring Pad 39A in the summer of 2017, when it lofted the BulgariaSat-1 and Intelsat 35e communications satellites, just 12 days and a few hours apart.

The $10 billion Starlink constellation was unveiled by Mr. Musk during an event in Seattle, Wash., back in January 2015, in which he identified it as a means of opening the way for low-cost broadband access to boost data-speeds and increase the availability of internet access around the world. He added that it could provide competitively-priced services to urban regions. Indeed, Federal Communications Commission (FCC) Chairman Ajit Pai stressed that Starlink has the potential to bring internet access to rural and underserved regions of the United States. Under the announced Starlink plans, an eventual network of around 12,000 satellites in very-low-Earth orbit would have the bandwidth potential to carry up to half of all backhaul communications traffic and up to a tenth of all local internet traffic in high-population-density cities.



The 60 flat-packed Starlink satellites, pictured aboard the Upgraded Falcon 9 payload fairing. Photo Credit: Elon Musk/Twitter

In November 2016, SpaceX filed an application with the FCC, in which it identified the proposed network as a “non-geostationary orbit satellite system”. The initial concept covered the Ku-band and Ka-band portions of the electromagnetic spectrum, respectively between 12-18 GHz and 26.5-40 GHz. By March 2017, a second orbital “shell” of satellites was filed with the FCC, using the V-band, a region not “heavily employed for commercial communications services”. The V-band covers 40-75 GHz and historically has been utilized for millimeter-wave radar research and other scientific investigations, but has acute potential for high-capacity terrestrial millimeter-wave communications systems.

All told, it was expected that Starlink would comprise 4,425 Ku-/Ka-band satellites at an altitude of 710 miles (1,150 km) and 7,518 V-band satellites at just 210 miles (340 km) above the Home Planet, producing a constellation of around 12,000 smallsat-sized satellites in low-Earth orbit by the mid-2020s. However, in November of last year, SpaceX made new regulatory filings with the FCC to alter its previously granted license to operate almost a third of the Ku-/Ka-band Starlink complement—some 1,584 satellites—at a much lower altitude, just 340 miles (550 km) above Earth. That request was approved last month by the FCC.

Operations at such low altitude, of course, are expected to suffer from exceptionally high atmospheric drag and a shorter nominal orbital lifetime. SpaceX has previously indicated that the satellites’ useful lives are expected to range from five to seven years apiece, after which they will be propulsively maneuvered to a “disposal orbit”, for controlled re-entry within 12 months of completing their missions.

A pair of test satellites, dubbed “MicroSat-1a” and “MicroSat-1b”, were originally slated to validate the broadband antenna platform for Starlink, traveling to orbit alongside one of the Iridium NEXT missions from Vandenberg Air Force Base, Calif. However, they were ultimately relegated to use as ground-based test articles, as development of the more capable “MicroSat-2a” and “MicroSat-2b” test satellites got underway in earnest.



The Tintin A and Tintin B test satellites were deployed in February 2018, alongside Spain’s Paz radar-imaging observation/reconnaissance satellite. Photo Credit: SpaceX

In February 2018, MicroSat-2a and 2b—subsequently renamed “Tintin A” and “Tintin B”—were launched from Vandenberg, riding piggyback alongside Spain’s Paz radar-imaging Earth-observation/reconnaissance satellite. The duo entered a circular orbit 319 miles (514 km) high and served to validate the design of a phased-array broadband antenna communications platform for Starlink, using five broadband array test ground stations in the western United States, together with three transportable ground stations.

In his Twitter comments over the weekend, Mr. Musk stressed that the 60 Starlink satellites aboard Wednesday’s mission are different from Tintin A and Tintin B. “These are production design,” he told his 26.4 million followers, “unlike our earlier Tintin demo sats.” He also noted the risk that “much will likely go wrong on first mission” and gave an indication of the kind of numbers of Starlinks needed in orbit to achieve capacity. “Also, six more launches of 60 sats needed for minor coverage, 12 for moderate.” This would appear to be in keeping with earlier allusions that at least two more Starlink-dedicated missions may fly later in 2019.

With 60 flat-packed Starlink payloads aboard Wednesday’s mission, the size of these satellites are believed to be in the “smallsat” class, with a mass range approximating 850 pounds (390 kg). Mr. Musk has previously indicated his intention to mass-produce them and “try to do for satellites what we’ve done for rockets”


Source: https://www.americaspace.com/2019/05/14/spacex-readies-first-batch-of-starlink-satellites-for-wednesday-night-launch/#more-108202

Online Orionid

  • Weteran
  • *****
  • Wiadomości: 14825
  • Very easy - Harrison Schmitt
Musk says Starlink “economically viable” with around 1,000 satellites
by Caleb Henry — May 15, 2019 [SN]


Each batch of 60 Starlink satellites will bring about a terabit of usable broadband capacity, according to SpaceX CEO Elon Musk. Credit: SpaceX

WASHINGTON — SpaceX shared details about its largely secretive Starlink constellation program March 15, providing updated targets for commercial service, details about satellite design and the thought process behind why the company’s upper target is 12,000 satellites — about six times the number functioning in orbit for the rest of the world combined.

SpaceX’s first launch with a large number of Starlink satellites was pushed back 24 hours, with a new launch window opening at 10:30 p.m. Eastern May 16. The Falcon 9 mission will carry 60 Starlink satellites.

Though the spacecraft lack intersatellite links and other features expected in later iterations, SpaceX CEO Elon Musk said the satellites mark the start of deployment for a constellation designed to deliver internet access to unreached and underserved parts of the world.

Musk, in a call with reporters, said SpaceX views 1,000 satellites as the point when Starlink becomes economically solid.

“For the system to be economically viable, it’s really on the order of 1,000 satellites,” he said. “If we are putting a lot more satellites than that in orbit, that’s a very good thing — it means there is a lot of demand for the system.”

SpaceX asked for and received U.S. market access for a constellation numbering almost 12,000 satellites. Until recently, regulatory filings with the U.S. Federal Communications Commission have been the main way information about SpaceX’s constellation was made publicly available.

Musk said reaching 12,000 satellites would indicate a “very successful outcome” for Starlink.

SpaceX President and COO Gwynne Shotwell said May 7 that the company plans three to seven Starlink launches this year.

Musk said subsequent Starlink launches would each carry roughly 60 satellites. Going forward, Musk said SpaceX  could launch 1,000 to 2,000 satellites a year using its Falcon family of rockets.

“It’s a heck of a lot of launches. We will hopefully have Starship active by the time we are anywhere near 12,000 satellites,” he said, referring to the next-generation fully reusable launch system SpaceX is developing.

There are roughly 2,100 operational satellites in orbit today from all the world’s satellite operators, according to a report from Bryce Space and Technology issued May 8.

Musk said Starlink will have continual coverage of limited geographies at around 400 satellites, or seven launches including tomorrow’s mission. Mark Juncosa, SpaceX’s vice president of vehicle engineering, said 12 Starlink launches would ensure coverage of the United States. After 24 launches, Starlink would cover most of the world’s population, and 30 launches would be sufficient to cover the planet, Juncosa said.

With every launch, SpaceX will add about a terabit of “usable capacity,” Musk said, and two to three terabits overall.

Satellite operators sometimes draw a distinction between usable capacity and aggregate capacity when discussing low-Earth-orbit constellations, since the constellations are generally designed for global coverage, but are unlikely to have customers in every location where beams are active.

SpaceX’s projection for Starlink puts its usable capacity higher than any single geostationary communications satellite in orbit today, and would significantly outpace any other publicly known low-Earth-orbit constellation under development. Telesat, which is planning a constellation of 300 satellites, estimates it will provide 8 terabits of “useful capacity.” The satellites in OneWeb’s first-generation constellation of 600 operational satellites and 50 spares are designed to carry 10 gigabits per second each, meaning the system should presumably offer 6 terabits per second of aggregate capacity (OneWeb did not respond to a May 14 request to confirm that number).


Updated Starlink designs

SpaceX launched two prototype Starlink satellites in February 2018. These new satellites will be significantly different, Musk said.

Musk said Starlink’s newest 60 satellites carry phased array antennas and ion propulsion units that run on krypton instead of the typical xenon gas. SpaceX chose krypton because it is less expensive than xenon, Musk said.

SpaceX’s first-generation satellites won’t have intersatellite links, but will be able to use ground stations as relays to “ground bounce” signals around the world, he said. Later generations would include intersatellite links and other upgrades, he said, though he didn’t give a timeframe for when those would be introduced.

Musk said SpaceX would like to keep Starlink satellites in orbit for four to five years before deorbiting and replacing them with newer, more capable models.


Antennas and customers

Musk said Starlink user terminals will also use phased array, electronically steered antennas — a technology widely considered essential for the success of low-Earth-orbit broadband constellations.

In contrast to traditional dish antennas, electronically steered systems can track two or more satellites simultaneously, meaning no loss in connection when satellites rise and set over the horizon.

Musk said Starlink terminals, leveraging work by SpaceX’s “chip team,” can switch between satellites in under a thousandth of a second, and will support a system where the overall latency is under 20 milliseconds.

Musk described the terminals as similar in size to a small or medium pizza. While Musk mainly talked about Starlink as a system to bridge the digital divide by connecting unreached peoples, Musk said the antennas could also serve the more lucrative markets of aviation and maritime that most satellite operators are pursuing. The antennas could also be used to connect cars, he said.

Musk didn’t say how much the antennas would cost, however, or when they would be available. Most electronically steered antennas are too expensive for consumers and businesses to utilize.

Musk said SpaceX has not tried to win customers for Starlink yet, believing it would be better to have a firm grasp on its constellation deployment schedule first. SpaceX will likely start selling connectivity later this year or early next year if all goes well, he said.

Musk said SpaceX is interested in signing telcos as customers, as well as governments that want to connect hard to reach parts of their countries.

SpaceX plans to use Starlink to generate more funding in support of its goal of establishing a colony on Mars, Musk said. Starlink revenue would also help fund a base on the moon, he said.


Source: https://spacenews.com/musk-says-starlink-economically-viable-with-around-1000-satellites/

Online Orionid

  • Weteran
  • *****
  • Wiadomości: 14825
  • Very easy - Harrison Schmitt
SpaceX releases new details on Starlink satellite design
May 15, 2019 Stephen Clark [SFN]


The mission patch for SpaceX’s first dedicated launch for the Starlink network. Credit: SpaceX

The 60 satellites SpaceX is set to launch Wednesday night, beginning the build-out of a broadband network of orbiting spacecraft that could eventually number thousands, are based on a new flat-panel design, with krypton-fueled plasma thrusters, high-power antennas, and a capability to autonomously steer away from other objects in space.

Each of the Starlink satellites weighs around 500 pounds (227 kilograms), according to SpaceX. Stacked together inside the payload shroud of a Falcon 9 rocket, the 60 satellites weigh 15 tons (13,620 kilograms), making the cargo on Wednesday night’s launch the heaviest ever lofted into orbit by SpaceX.

The new mass record bests the weight of SpaceX’s fully-fueled Crew Dragon spacecraft, which launched March 2 on an unpiloted test flight to the International Space Station.

In a press kit released early Wednesday, SpaceX disclosed new information about the Starlink satellites’ design and functionality. Each Starlink spacecraft has a flat-panel design with multiple high-throughput antennas and a single solar array, according to information released in the press kit.

The Starlink satellites carry Hall thrusters, which use electricity and krypton gas to generate an impulse, to maneuver in orbit, maintain altitude and guide the spacecraft back into the atmosphere at the end of their mission.

Hall thrusters provide a more fuel-efficient form of propulsion than conventional liquid propellants, but most satellites that use Hall thrusters consume xenon gas. Krypton is less expensive than xenon, but offers less thrust efficiency, according to a 2011 paper presented by U.S. Air Force and satellite industry engineers.

The satellites also host optical trackers to detect space debris, allowing the craft to autonomously avoid collisions with other objects in space.

Proposals by SpaceX and other would-be commercial broadband providers to launch thousands of new satellites into orbit have raised questions about traffic management. SpaceX originally intended to launch the first batch of Starlink satellites to a higher 741-mile-high (1,150-kilometer) orbit, but the company requested authority from the Federal Communications Commission last year to begin operating the network at a lower altitude.

The FCC approved the request last month.

SpaceX officials said the lower operating altitude for the first Starlink satellites will help assuage space debris concerns. If a Starlink relay station in the lower orbit fails, atmospheric drag will bring the satellite back to Earth within about five years.

“Additionally, 95 percent of all components of this design will quickly burn in Earth’s atmosphere at the end of each satellite’s life cycle — exceeding all current safety standards — with future iterative designs moving to complete disintegration,” SpaceX said in the press kit published early Wednesday.

The 229-foot-tall (70-meter) Falcon 9 rocket is set for liftoff from Cape Canaveral’s Complex 40 launch pad during a 90-minute window that opens at 10:30 p.m. EDT Wednesday (0230 GMT Thursday).

There is an 80 percent chance of good weather for liftoff during Wednesday night’s launch window, according to the U.S. Air Force’s 45th Weather Squadron. SpaceX plans to recover the Falcon 9’s first stage booster, which flew on two previous missions in September 2018 and in January, on the company’s drone ship a few hundred miles northeast of Cape Canaveral.

The mission will be SpaceX’s sixth launch of the year, and the 71st flight of a Falcon 9 rocket since 2010.

The 60 spacecraft packed on top of the Falcon 9 rocket for launch Wednesday introduce a new satellite design SpaceX intends to mass-produce at a factory in Redmond, Washington, to populate a fleet that could eventually number nearly 12,000 Internet relay nodes in low Earth orbit.

SpaceX has closely held details about the Starlink satellite layout, including basic information such as the number of spacecraft slated to fly on the company’s first rocket launch dedicated to the broadband network. Elon Musk, SpaceX’s founder and CEO, revealed in a tweet Saturday that 60 satellites will be aboard the Falcon 9 rocket when it takes off from Florida’s Space Coast.

Musk also tweeted a picture showing the 60 satellites stacked in launch configuration, ready for encapsulation inside the Falcon 9’s payload fairing.



SpaceX is set to launch 60 satellites to begin deployment of the company’s Starlink broadband network, which eventually aims to beam Internet signals to consumers around the world. Credit: SpaceX

SpaceX’s Starlink fleet is one of several commercial projects in development to beam Internet connectivity around the world. OneWeb launched the first six of its planned 648 satellites in February, with up to 100 more spacecraft scheduled for launch by early 2020.

And Amazon, backed by the fortune of billionaire Jeff Bezos, is looking to join the race to provide broadband services from satellite constellations.

SpaceX’s Starlink fleet is reportedly set to cost around $10 billion, with nearly 12,000 Ku-band, Ka-band and V-band satellites positioned in at different altitudes in multiple orbital planes. The first 1,584 Starlink satellites are slated to operate in orbits 341 miles (550 kilometers) above Earth, spread in 24 orbital planes inclined 53 degrees to the equator.

The Falcon 9 rocket launching Wednesday will begin deploying the 60 Starlink satellites around 62 minutes after liftoff. The launcher will target a 273-mile-high (440-kilometer) orbit for the separation sequence, and the satellites will activate their Hall-effect thrusters to raise their altitude to their 341-mile-high operating orbit.

SpaceX launched two Starlink demonstration satellites in February 2018 as piggyback payloads on a Falcon 9 launch from California. The spacecraft launching Wednesday have a different design, and are smaller than the testbeds launched last year.

“SpaceX designed Starlink to connect end users with low-latency, high-bandwidth broadband services by providing continual coverage around the world using a network of thousands of satellites in low Earth orbit,” SpaceX said in the press kit. “To manufacture and launch a constellation of such scale, SpaceX is using the same rapid iteration in design approach that led to the successes of Falcon 1, Falcon 9, Falcon Heavy, and Dragon.

“As such, Starlink’s simplified design is significantly more scalable and capable than its first experimental iteration,” SpaceX said.

“This mission will push the operational capabilities of the satellites to the limit,” SpaceX said. “SpaceX expects to encounter issues along the way, but our learnings here are key to developing an affordable and reliable broadband service in the future.”


Source: https://spaceflightnow.com/2019/05/15/spacex-releases-new-details-on-starlink-satellite-design/

Online Orionid

  • Weteran
  • *****
  • Wiadomości: 14825
  • Very easy - Harrison Schmitt
SpaceX’s first 60 Starlink broadband satellites deployed in orbit
May 24, 2019 Stephen Clark [SFN]


A SpaceX Falcon 9 rocket lifts off Thursday night from pad 40 at Cape Canaveral Air Force Station, Florida. Credit: SpaceX

SpaceX successfully delivered the first 60 members of the company’s Starlink broadband satellite fleet to orbit Thursday night after a launch from Cape Canaveral.

The 60 small satellites, each with a flat-panel design and built by an in-house SpaceX team, will be joined by hundreds more Starlink craft over the next year to fill out the network’s preliminary constellation. Eventually, SpaceX says thousands of Starlink satellites may be launched to provide high-speed Internet services to consumers around the world.

Thursday night’s launch from Cape Canaveral was the first mission dedicated to the multibillion-dollar Starlink project.

“This is one of the hardest engineering projects I’ve ever seen done, and it’s been executed really well,” said Elon Musk, SpaceX’s founder and CEO, during a press briefing last week. “There is a lot of new technology here, and it’s possible that some of these satellites may not work, and in fact a small possibility that all the satellites will not work.

“We don’t want to count anything until it’s hatched, but these are, I think, a great design and we’ve done everything we can to maximize the probability of success,” he said.

A 229-foot-tall (70-meter) Falcon 9 rocket took off from Cape Canaveral’s Complex 40 launch pad at 10:30 p.m. EDT Thursday (0230 GMT Friday) to begin the journey into orbit atop 1.7 million pounds of thrust from nine Merlin main engines.

SpaceX tried to launch the mission twice last week, but unfavorable upper level winds forced the team to call off one launch attempt. Then SpaceX scrubbed another countdown the next day to allow time for engineers to update the software on the Starlink satellites, delaying the mission by a week.

Heading northeast from Florida’s Space Coast, the launcher’s first stage finished its job on the mission in two-and-a-half minutes, then separated and accomplished an on-target propulsive landing on SpaceX’s drone ship in the Atlantic Ocean.

The landing punctuated the booster’s third flight, following successful launches and recoveries last September and in January. SpaceX could refurbish and reuse the rocket again.

Recovery teams in the Atlantic also retrieved the two-part nose cone from the Falcon 9 rocket, which fell into the sea under parachutes. SpaceX has not yet re-flown a payload fairing.

The Falcon 9’s second stage engine shut down just shy the flight’s nine-minute point, and the rocket coasted across the Atlantic, over Europe and the Middle East, then reignited its Merlin engine for a brief maneuver to nudge the Starlink satellites into a targeted orbit 273 miles (440 kilometers) above Earth.

The rocket commanded release of the 60 Starlink satellites, each weighing around 500 pounds (227 kilograms), at 11:32 p.m. EDT (0332 GMT) as the launcher soared over a ground station in Tasmania. Live video transmitted through the tracking station showed the satellites flying free of the Falcon 9’s second stage, backdropped by the curvature of the Earth.

Stacked together inside the payload shroud of the Falcon 9 rocket, the 60 satellites weighed 15 tons (13,620 kilograms), making the cargo on Thursday night’s launch the heaviest ever lofted into orbit by SpaceX. The new mass record bested the weight of SpaceX’s fully-fueled Crew Dragon spacecraft, which launched March 2 on an unpiloted test flight to the International Space Station.

Musk described the unique Starlink separation scheme in a pre-launch press briefing.

“It will be a little bit different looking deployment than people are used to,” Musk told reporters last week. “It’s going to be a very slow deployment where we rotate the stage, and each of the satellites on the stack has a slightly different amount of rotational inertia.”

Live video from a camera on-board the upper stage showed the rocket begin a spin maneuver just before the deployment. The 60 flat-panel satellites separated in a clump, instead of one-at-a-time or in pairs, as spacecraft often do when releasing from the launch vehicle.

“So there’s not actually a spring-based or specific deployment mechanism per satellite,” Musk said. The satellites will kind of be deployed, it’s almost like spreading a deck of cards on a table. This will be kind of weird compared to normal satellite deployments.”

The Starlink satellites could be seen slowly dispersing soon after separating from the Falcon 9, before SpaceX ended its live webcast of the mission. The upper stage later conducted a deorbit burn to drop back into the atmosphere and burn up.

Musk tweeted after Thursday night’s launch that all 60 Starlink satellites were “online.” He said the satellites were expected to extend their power-generating solar panels and activate their ion thrusters within a few hours.

Each satellite carries a krypton ion propulsion system and Ku-band antennas to continue in-orbit demonstrations of SpaceX’s planned broadband network, which may eventually number up to 12,000 small relay stations in low Earth orbit.

Future Starlink satellites will carry Ka-band and V-band radio transmission hardware, along with laser inter-satellite links to allow signals to bounce between spacecraft in orbit, rather than going through a ground station.

Each Starlink spacecraft has a flat-panel design with four high-throughput phased array antennas and a single solar array, according to information released by SpaceX. The company built the satellites at a new facility in Redmond, Washington.

SpaceX says the Starlink satellites are the first to use krypton-fueled ion thrusters. The propulsion system ionizes the krypton gas and uses electricity to accelerate the atoms out the back of the engine to produce a low level of thrust.

Ion thrusters provide a more fuel-efficient form of propulsion than conventional liquid propellants, but most satellites that use ion propulsion consume xenon gas. Krypton is less expensive than xenon, but offers lower thrust efficiency, according to a 2011 paper presented by U.S. Air Force and satellite industry engineers.

The satellites also have computer smarts allowing the craft to autonomously avoid collisions with other objects in space.

Proposals by SpaceX and other would-be commercial broadband providers planning to launch thousands of new satellites into orbit have raised questions about traffic management. SpaceX originally intended to launch the first batch of Starlink satellites to a higher 741-mile-high (1,150-kilometer) orbit, but the company requested authority from the Federal Communications Commission last year to begin operating the network at a lower altitude.

The FCC approved the request last month.



Artist’s concept of a Starlink satellite with its solar array wing unfurled. Credit: SpaceX

SpaceX officials said the lower operating altitude for the first Starlink satellites will help assuage space debris concerns. If a Starlink relay station in the lower orbit fails, atmospheric drag will bring the satellite back to Earth within about five years.

“Additionally, 95 percent of all components of this design will quickly burn in Earth’s atmosphere at the end of each satellite’s life cycle — exceeding all current safety standards — with future iterative designs moving to complete disintegration,” SpaceX said in the press kit on the Starlink mission.

SpaceX launched two Starlink test satellites as piggyback payloads on a Falcon 9 launch last year, but the craft launched Thursday night are lighter and use a different design.

Using their krypton thrusters, the new Starlink satellites will climb into higher orbits 341 miles (550 kilometers) above Earth, at an inclination of 53 degrees to the equator.

Past initiatives to create an expansive communications satellite network in low Earth orbit, a regime a few hundred miles above Earth, have met technical and financial headwinds. Traditional communications satellites fly in higher geostationary orbits more than 22,000 miles (nearly 36,000 kilometers) above the equator, with a single spacecraft covering a wide geographic region.

In lower orbits, the Starlink satellites will bounce signals from user-to-user via an intricate web of radio connections through ground stations, and eventually through the inter-satellite laser cross-links.

“The goal of the Starlink system is to provide high bandwidth, low latency connectivity, ideally throughout the world provided we get regulatory approval, and this would provide connectivity to people that don’t have any connectivity today, or where it’s extremely expensive and unreliable as well as providing options for people who may have connectivity today in developed areas of the world but it’s very expensive,” Musk said. “This will provide a competitive option for them.”

Starlink is one of several companies working on constellations of small broadband satellites in low Earth orbit. Backed by a roster of international investors, including Japan’s SoftBank Group, OneWeb launched its first six satellites in February on a Soyuz rocket, with plans to send hundreds more into orbit over the next two years, and Amazon says it plans to build a network consisting of thousands of satellites for Internet service.

“There’s a lot of fundamental goodness about Starlink,” he said. “We just want to make sure the appropriate caveats are there. There’s a lot of technology, this is very hard, and quite frankly in the past, the success of low-Earth orbit communications constellations, I believe none have successfully gone into operation without going bankrupt.”

SpaceX has secured regulatory approval from the Federal Communications Commission for nearly 12,000 Starlink satellites broadcasting in Ku-band, Ka-band and V-band frequencies, with groups of spacecraft positioned at different altitudes and in various planes in low Earth orbit. But the early focus is on launching hundreds of the satellites to establish a network that covers most of the world’s population.

“It’s important to distinguish between initial operational capability, which is around the 400-satellite level, and then significant operational capability is around 800-satellite level, and thereafter, it’s about adding more and more satellites and more orbital planes of satellites as we get more usage of the system and we get bandwidth constrained,” Musk said. “One does not need anywhere near 10,000 satellites to be effective. … We’ll start selling service initial around the 400th satellite launch and then make sure our production and launch of satellites stays ahead of user demand.”

If there’s demand, SpaceX could scale up the network to reach the 12,000-satellite threshold.

After the first Starlink launch, SpaceX plans between two and six additional Starlink missions later this year to begin building out the first phase of the network in orbit 341 miles above Earth, according to Gwynne Shotwell, SpaceX’s president and chief operating officer.

SpaceX debuted a new Starlink websitenew Starlink website soon after Thursday night’s launch. According to the website, the Starlink system will provide broadband service over the latitudes of the northern United States and Canada after six additional launches. After 24 launches, the network should cover the populated world.

Musk said the user terminal consumers will use to connect with the Starlink network is a flat antenna — about the size of a small or medium pizza — that is relatively simple to set up. He did not say how much the user terminal will cost, or disclose the expected price of a subscription to Starlink’s broadband service.

In addition to consumer-scale broadband, the Starlink network could help large telecom operators in rural areas. Airplanes and ships are also prime markets for Starlink.

“We think this could be really helpful to telcos (telecom operators) by providing connectivity that they need for the most difficult to serve customers, as well as providing data backhaul services so that a telco could put down a 5G cell tower somewhere instead of digging a fiber trench over potentially hundreds of miles,” Musk said. “That 5G cell tower could do data backhaul through our satellite system.”

Musk said SpaceX has enough money to get the privately-funded Starlink system operational. A filing with the Securities and Exchange Commission last month showed SpaceX had raised $44 million in a $400 million fundraising round, and a filing in January showed SpaceX had raised $273 million of a planned $500 million in an earlier round.

But Musk told reporters last week that SpaceX’s funding rounds have been “oversubscribed,” and suggested the information contained in the regulatory filings was “out-of-date.”

“This is obviously a multibillion-dollar endeavor,” Musk said. “So we’ve got the cash flow that we generate from our normal launch operations, launching commercial satellites and launching Dragon to the space station, that kind of thing, as well as capital that we have raised. At this point, it looks like we have sufficient capital to get to an operational level, but of course, if things go wrong and there are unexpected issues, we will need to raise more capital in that situation.”

Tim Farrar, a satellite and telecommunications industry consultant, said the first launches for the SpaceX and OneWeb broadband networks puts pressure on other players.

“We’re going to be involved in a race between SpaceX and OneWeb to launch as many satellites as possible,” Farrar said in an interview with Spaceflight Now before the Starlink launch. “It sort of limits the opportunities for other constellations like Telesat to find partners and raise money, unless they’re going find some deal with Jeff Bezos and Amazon.

“OneWeb was talking … about launching as many 100 satellites by the end of this year or early next year. SpaceX is talking about having multiple additional launches over the next six to 12 months,” said Farrar, president of TMF Associates, a consulting firm in Menlo Park, California. “At that point you do have a question … Is there room for another player that’s going to take a couple of years before they can even launch any more satellites?”

For Musk, the Starlink system is not only a business opportunity. It could also offer a potential revenue stream for SpaceX to pay for costly rocket development projects, such as the company’s Starship and Super Heavy vehicles, which Musk envisions as a reusable multi-purpose vehicle for huge satellite launches and interplanetary voyages with cargo and people.

“We see this as a way for SpaceX to generate revenue that can be used to develop more and more advanced rockets and spaceships, and we think this is a key stepping stone on the way toward establishing a self-sustaining on Mars and a base on the moon,” Musk said. “We believe we can use the revenue from Starlink to fund Starship.”


Source: https://spaceflightnow.com/2019/05/24/spacexs-first-60-starlink-broadband-satellites-deployed-in-orbit/

Polskie Forum Astronautyczne


Online Orionid

  • Weteran
  • *****
  • Wiadomości: 14825
  • Very easy - Harrison Schmitt
Little legal recourse for astronomers concerned about Starlink
by Jeff Foust — June 3, 2019 [SN]


An image released by the IAU June 3 shows trails made by dozens of Starlink satellites as they passed through the field of view of a telescope during an observation shortly after launch. The IAU noted in its statement that the density and brightness of the satellites in this image is not representative of their appearance in their final orbital configuration. Credit: Victoria Girgis/Lowell Observatory

WASHINGTON — Despite complaints by individual astronomers and astronomical organizations, legal experts say there is little they can do under existing federal law and regulations to halt the deployment of SpaceX’s Starlink satellites.

SpaceX launched the first set of 60 Starlink satellites May 23. The next evening, amateur astronomers noticed them passing in a closely-bunched train, bright enough to be easily seen by the naked eye. The satellites have subsequently spread out in the sky and raised their altitude, becoming harder to see but occasionally flaring to brighter magnitudes.

The initial appearance has alarmed many professional astronomers, who are concerned that the full Starlink constellation — SpaceX has licenses from the Federal Communications Commission for up to about 12,000 satellites — could interfere with groundbased astronomy. In some scenarios, hundreds of satellites could be visible in the sky at any given time, making it more likely one will cross the field of view of a telescope and disrupt an observation.

“The rapid increase in the number of satellite groups poses an emerging threat to the natural nighttime environment and our heritage of dark skies,” said the International Dark-Sky Association, a group devoted primarily to addressing terrestrial light pollution threats to astronomy, in a May 29 statement.

That statement also included an anecdote from James Lowenthal, a professor of astronomy at Smith College, who observed the initial Starlink train while on an outing with students. Seeing the satellites, he said, was a “shocking and devastating sight.”

The International Astronomical Union (IAU), an organization best known for overseeing nomenclature for celestial bodies, also weighed in, noting the potential for satellite constellations such as Starlink to interfere with both optical and radio astronomy.

“Satellite constellations can pose a significant or debilitating threat to important existing and future astronomical infrastructures, and we urge their designers and deployers as well as policy-makers to work with the astronomical community in a concerted effort to analyze and understand the impact of satellite constellations,” the IAU said in a June 3 statement. “We also urge appropriate agencies to devise a regulatory framework to mitigate or eliminate the detrimental impacts on scientific exploration as soon as practical.”

However, currently in the United States there are no regulations that apply to the appearance of satellites in the night sky, beyond a prohibition in federal law against “obtrusive space advertising,” defined as “advertising in outer space that is capable of being recognized by a human being on the surface of the Earth without the aid of a telescope or other technological device.” Simply being able to see a satellite from the ground, legal experts say, does not qualify as obtrusive space advertising.

The Starlink satellites are licensed by the FCC, and their launches on Falcon 9 rockets are licensed by the Federal Aviation Administration. Neither licensing process explicitly includes a consideration of the impact of satellites on the night sky.

Michael Listner of Space Law and Policy Solutions said in a June 3 interview that the only legal recourse for astronomers would be to file a case in federal court, including seeking a temporary injunction to block future launches. He was skeptical, though, that such a case would be successful, since damages to astronomers from constellations like Starlink are only “speculative” at this time.

Others noted that astronomers missed opportunities to comment earlier, such as when the FCC was considering SpaceX’s original application for the Starlink constellation or its more recent modification seeking approval to operate some satellites at a lower altitude. The public docket for that application, on the FCC’s website, primarily consists of letters and petitions from other satellite operators concerned about radiofrequency interference.

The only comment from astronomers came from the National Radio Astronomy Observatory (NRAO), which filed a letter in February 2018 noting that efforts between SpaceX and NRAO to coordinate frequency usage “trailed off inconclusively” in mid-2017.

The NRAO, in a May 31 statement, said it and the Green Bank Observatory in West Virginia had been working with SpaceX about radiofrequency interference issues. “These discussions have been fruitful and are providing valuable guidelines that could be considered by other such systems as well,” the NRAO stated. “To date, SpaceX has demonstrated their respect for our concerns and their support for astronomy.”

SpaceX executives said they’re aware of concerns by astronomers about the effects Starlink satellites could have on their observations. Elon Musk, founder and chief executive of the company, said in a May 27 tweet that he had asked engineers to look into “albedo reduction” of future Starlink satellites that would make them reflect less sunlight and thus appear dimmer.

“If we need to tweak sat orientation to minimize solar reflection during critical astronomical experiments, that’s easily done,” he said in another tweet. He didn’t define what would be considered a “critical” observation.

Gwynne Shotwell, president of SpaceX, said at a May 29 symposium at the Massachusetts Institute of Technology that the company was still trying to understand what causes the satellites to often appear bright while “working on ways to make that less severe,” according to one attendee.


Source: https://spacenews.com/little-legal-recourse-for-astronomers-concerned-about-starlink/

Online Orionid

  • Weteran
  • *****
  • Wiadomości: 14825
  • Very easy - Harrison Schmitt
Contact lost with three Starlink satellites, other 57 healthy
by Caleb Henry — July 1, 2019 [SN]


Of the 60 Starlink satellites launched in May, 45 have completed orbit raising, five are in the process of orbit raising, and another five are completing system checks. Credit: SpaceX

WASHINGTON — Three of the 60 satellites SpaceX launched last month to begin its broadband megaconstellation have lost contact with ground control teams, a SpaceX spokesperson said June 28.

Those three satellites will deorbit “passively,” the spokesperson said, meaning Earth’s gravity and atmospheric drag will pull them down until they burn up in the atmosphere.

Observers had noticed some Starlink satellites had not initiated orbit raising after being released May 23 from a Falcon 9 upper stage into a 440-kilometer low Earth orbit. SpaceX said May 31 that all 60 satellites were initially responsive.

SpaceX’s spokesperson, in their June 28 statement, said the company will intentionally deorbit two functioning satellites as well, in order to test the spacecraft’s ability to propulsively deorbit.

“Three satellites which initially communicated with the ground but are no longer in service, will passively deorbit,” the spokesperson said. “Due to their design and low orbital position, all five deorbiting satellites will disintegrate once they enter Earth’s atmosphere in support of SpaceX’s commitment to a clean space environment.”

SpaceX Founder Elon Musk stressed that the early Starlink satellites had a high risk of not working given the quantity of newly developed technology they carry.

“It’s possible that some of these satellites may not work, and in fact [there’s a] small possibility that all of the satellites will not work,” he said during a May 15 call with reporters. “But these are a great design and we’ve done everything we can to maximize probability of success.”

SpaceX sought and received approval from the U.S. Federal Communications Commission to operate a portion of its megaconstellation in a 550-kilometer orbit instead of its originally planned 1,150-kilometer altitude. The lower orbit means the satellites will deorbit within five years without propulsion, according to SpaceX.

SpaceX’s spokesperson said 45 of the 60 Starlink satellites have reached their target altitude. Another five are in the process of orbit raising, and the last five are completing “check-outs” before also orbit raising, the spokesperson said.

The 60 satellites SpaceX launched in May are not the final design for its constellation of up to 12,000 satellites. The satellites lack inter-satellite links expected for future generations, and have some dissimilar features so that the company can test different technologies.

“SpaceX implemented slight variations across the 60 satellites in order to maximize operational capability across the fleet,” the spokesperson said. “While we are pleased with the performance of the satellites so far, SpaceX will continue to push the operational capabilities of the satellites to inform future iterations.”

The spokesperson said SpaceX will use the early Starlink satellites to tests signal speed and capacity by “streaming videos and playing some high bandwidth video games using gateways throughout North America.”

SpaceX says having satellites at 550 kilometers means it can achieve latencies of around 15 milliseconds, a noticeable difference between geostationary satellites that can have around half a second or more of signal lag.

SpaceX claims to be the first among the 11 participants in the Federal Communications Commission’s Ku-Ka-band spectrum processing round to have Ku-band non-geosynchronous satellites operating over the United States. SpaceX told the FCC in a June 12 letter that being first means the company met conditions to have first choice in the U.S. for Ku-band “home base” radio frequencies in the event of in-line interference with another non-geosynchronous satellite operator.

Two other constellation companies dispute SpaceX’s claim, however. London-based OneWeb and Kepler Communications of Canada have Ku-band satellites in orbit and FCC authorization to provide communications services in the United States. OneWeb launched six of an initial 648-satellite broadband constellation in February, and Kepler Communications has two of a planned 140 Internet-of-Things satellites in orbit, the first of which launched in February 2018.


Source: https://spacenews.com/contact-lost-with-three-starlink-satellites-other-57-healthy/

Online Orionid

  • Weteran
  • *****
  • Wiadomości: 14825
  • Very easy - Harrison Schmitt
Starlink failures highlight space sustainability concerns
by Jeff Foust — July 1, 2019 [SN]


A stack of Starlink satellites being prepared for launch. A five percent failure rate for the first set of 60 satellites has heightened concerns that megaconstellations could leave hundreds of dead satellites in long-lived orbits. Credit: SpaceX

WASHINGTON — The failure of at least five percent of the first batch of SpaceX Starlink satellites has put a spotlight on the growing concerns that satellite megaconstellations could litter low Earth orbit with hundreds of dead satellites.

SpaceX said in a June 28 statement that three of the 60 Starlink satellites the company launched May 23 are no longer responding to commands from the ground and appear to be dead. The company said those satellites will deorbit naturally, burning up in the Earth’s atmosphere.

In addition to the three failed satellites, five others are still raising their orbits to their planned altitude of 550 kilometers, while five others are still undergoing tests in their initial, lower orbits. It wasn’t clear when, or if, those satellites would reach their operational orbit.

SpaceX had stressed prior to the launch that these satellites were, in effect, experimental, and had a higher risk of on-orbit failures as the company demonstrates their key technologies. Launching them into lower orbits ensures they should deorbit in a matter of a few years.

At the Secure World Foundation’s Summit for Space Sustainability here last week, government and industry officials said they were concerned that proposed megaconstellations of thousands of satellites could, with similar failure rates, leave hundreds of dead satellites in low Earth orbit, a particular concern at some of the higher altitudes proposed for those systems where it can take centuries for satellites to naturally deorbit.

Matt Desch, chief executive of Iridium, dubbed dead satellites “rocks” during an on-stage interview at the conference June 26. “What if you launch 1,000 satellites, 5,000 satellites, 12,000 satellites?” he asked. “Say, 10 percent create rocks. We are creating an environment that may make LEO an environment that isn’t sustainable.”

Desch speaks from his own company’s experience. The company has emphasized reliability — it’s noted all 75 of its next-generation satellites are functioning — and sustainability, including taking first-generation satellites out of orbit within a matter of weeks once retired from the fleet.

Those first-generation satellites were designed to operate seven years, but in some cases lasted three times as long. Yet, nearly a third suffered in-orbit failures and cannot be deorbited. “We’ve created, inadvertently, using highly reliable components, almost 30 percent rocks in space that will be up there a long time,” he said.

That 30 percent failure rate is for the company’s original fleet of 95 satellites. “It freaked everybody out to launch 95 satellites” back in the 1990s, he recalled. “Now, of course, we look like slackers.”

Holger Krag, head of the space safety program office at the European Space Agency, noted in a June 25 talk at the meeting that many satellite operators aren’t adhering to guidelines that call for deorbiting satellites within 25 years after end of life. He found that only 30 percent of operators were implementing proper post-mission disposal of their spacecraft.

“This is not enough,” he said. Current trends in the growth of space objects, including satellites and debris, is little different than if operators took no measures at all to mitigate space debris. “We need to get much better.”

There was no shortage of ideas for doing so presented at the meeting, ranging from active debris removal to shortening post-mission disposal times to the use of failsafe automated deorbit systems that would remove satellites from orbit even if they suffer a mission-ending anomaly.

One speaker, Didier Alary of the University of Toulouse, suggested the creation of an “eco-tax” similar to fees charged in some countries to cover the recycling of appliances, in this case charged to satellite operators based on the number of satellites and how they adhere to sustainability guidelines. The funds collected from such taxes would go towards efforts to remove space debris.

While there wasn’t clear support for that proposal, Desch was among those calling for a regulatory regime to improve space sustainability, saying that industry likely wouldn’t be able to self-regulate. “As long as there’s a set of rules that everybody has to follow, that’s not unusual,” he said. “I think they should be international in scope and everybody has to follow them, and if you don’t, there might need to be penalties or something.”

Desch did praise SpaceX for seeking and winning Federal Communications Commission approval to operate much of its Starlink constellation at 550 kilometers, versus 1,150 kilometers as originally planned. SpaceX said it lowered the satellites to reduce latency, but at that lower altitude the satellites will naturally deorbit within five years without propulsion.

“One of the greatest moves made in the last two or three months on this whole issue is SpaceX deciding to lower its altitude,” he said, while acknowledging there were reasons beyond space sustainability for operating at a lower orbit. “I’m just thrilled they made that decision. It’s a very responsible decision.”


Source: https://spacenews.com/starlink-failures-highlight-space-sustainability-concerns/

Online Orionid

  • Weteran
  • *****
  • Wiadomości: 14825
  • Very easy - Harrison Schmitt
SpaceX plans 24 Starlink launches next year
by Caleb Henry — September 10, 2019 [SN]


SpaceX President Gwynne Shotwell speaks Sept. 10 at World Satellite Business Week in Paris. Credit: SpaceNews/Brian Berger

PARIS — SpaceX hopes to launch 24 Starlink missions in 2020 as the company builds out a broadband megaconstellation that could ultimately number close to 12,000 satellites, a company executive said Sept. 10.

SpaceX’s Starlink launch cadence will likely average “two a month,” in addition to customer launches, Gwynne Shotwell, SpaceX’s president and chief operating officer, said at the World Satellite Business Week conference here.

“Next year, I hope we launch 24 Starlinks,” Shotwell said.

Shotwell said SpaceX might launch more Starlink missions this year, but the final number will depend on customer missions. SpaceX will prioritize launching customers before its own broadband satellites, she said.

“If some customers move out, I’ll have some Starlink launches — maybe up to four Starlink launches this year — but we won’t push a customer out for that, so we will wait and see what the end of the year looks like and see what we can fit in.”

Shotwell didn’t specify if Starlink missions will be solely on Falcon 9s or if they will also include Falcon Heavy launches.

After inducing launch delays for customers due to Falcon 9 rocket failures in 2015 and 2016, SpaceX is now caught up on late missions — so much so that rockets are ready before customer satellites, Shotwell said.

“This is the first year that we are seeing that we are now ready to fly our customers before they are ready,” she said.

Shotwell estimated SpaceX will do seven to eight more missions this year, including Starlink. Previously, the company estimated 24 to 25 launches in 2019, but several customer missions weren’t ready in time, she said.

SpaceX has flown 10 rockets this year — eight Falcon 9s and two Falcon Heavies. Shotwell didn’t say how many total launches SpaceX plans in 2020, only that it is “much higher” than this year’s projected max of 18.

SpaceX launched its first 60 Starlink satellites in May using a Falcon 9 rocket. The company is deorbiting at least five of those satellites — three due to malfunctions and two to test intentional deorbiting procedures.

When — and with what coverage — Starlink begins service may hinge on the U.S. Federal Communications Commission’s decision on a filing SpaceX made in late August. SpaceX asked the FCC to allow it to triple the number of orbital planes, or pathways, for Starlink satellites at 550 kilometers. By using 72 orbital planes instead of 24, Starlink can extend its reach to customers in lower latitudes more quickly and with fewer launches, SpaceX said.

In May, prior to the filing, SpaceX CEO Elon Musk said that Starlink will have consistent partial coverage with 400 satellites, and should be “economically viable” at 1,000 satellites.

Mark Juncosa, SpaceX’s vice president of vehicle engineering, said in May that 30 Starlink launches would be sufficient for global coverage based on the company’s deployment plans at the time.


Source: https://spacenews.com/spacex-plans-24-starlink-launches-next-year/

Online Orionid

  • Weteran
  • *****
  • Wiadomości: 14825
  • Very easy - Harrison Schmitt
Odp: [AS]SpaceX Readies First Batch of Starlink Satellites for Wednesday Night Launch
« Odpowiedź #8 dnia: Październik 19, 2019, 22:39 »
SpaceX submits paperwork for 30,000 more Starlink satellites
by Caleb Henry — October 15, 2019, Updated Oct. 15 at 6:18 p.m. Eastern to include a statement from SpaceX. [SN]


SpaceX could one day operate 42,000 Starlink satellites if it builds and launches 30,000 in addition to the 12,000 for which it already has FCC approval. Credit: SpaceX

WASHINGTON — SpaceX has asked the International Telecommunication Union to arrange spectrum for 30,000 additional Starlink satellites.

SpaceX, which is already planning the world’s largest low-Earth-orbit broadband constellation by far, filed paperwork in recent weeks for up to 30,000 additional Starlink satellites on top of the 12,000 already approved by the U.S. Federal Communications Commission.

The FCC, on SpaceX’s behalf, submitted 20 filings to the ITU for 1,500 satellites apiece in various low Earth orbits, an ITU official confirmed Oct. 15 to SpaceNews.

SpaceX deployed its first 60 Starlink satellites in May and plans to launch hundreds — potentially over a thousand — more in the year ahead.

The ITU, a United Nations entity, coordinates spectrum at the international level for satellite operators to prevent signal interference and spectrum hogging. National regulators submit filing on behalf of their country’s satellite operators.

SpaceX’s ITU filings contain details about frequency usage, proposed orbital altitudes, and the number of satellites it desires. The filings do not say when SpaceX hopes to launch the satellites, or other details such as spacecraft throughput and deorbit timelines.

ITU filings are an early step in deploying a satellite system, and are often made years before a company plans to build launch spacecraft. SpaceX will be required to disclose more details about its constellation when applying with the FCC for access to the U.S. market to offer broadband services, like it did with the 12,000-satellite constellation it began launching in May.

In its filings, SpaceX said the additional 30,000 satellites would operate in low Earth orbit at altitudes ranging from 328 kilometers to 580 kilometers.

SpaceX said the satellites will have steerable spot beams to link with customers, and “omnidirectional” beams for spacecraft telemetry, tracking and control functions.

Filings trigger a seven-year deadline whereby the satellite operator, in this case SpaceX, must launch at least one satellite with its requested frequencies and operate it for 90 days. Once spectrum rights have been assigned through this “bring into use” procedure, other ventures must design their systems to avoid interference with the newly minted incumbent operator.

The ITU is expected to change its “bring into use” rules during the upcoming World Radiocommunication Conference, which takes place from Oct. 28 to Nov. 22 in Sharm el-Sheikh, Egypt. Regulators intend to set more stringent rules for megaconstellation ventures, requiring them to launch percentages of their total constellation by to-be-determined deadlines in order to keep their priority spectrum rights.

It is not guaranteed that, by submitting numerous filings, SpaceX will build and launch 30,000 more satellites. Tim Farrar, a telecom analyst critical of SpaceX, tweeted that he was doubtful the ITU will be able to review such big filings in a timely manner. He sees the 20 separate filings as a SpaceX effort to “drown the ITU in studies” while proceeding with its constellation.

A SpaceX spokeperson declined to respond to Farrar’s comments, but sent SpaceNews a statement saying it “SpaceX is taking steps to responsibly scale Starlink’s total network capacity and data density to meet the growth in users’ anticipated needs.”

The United Nations Office for Outer Space Affairs said in April that approximately 8,500 satellites, probes, landers, crewed spacecraft, cargo craft and space station flight elements have been launched into Earth orbit or beyond since 1957, when Sputnik launched. If SpaceX launches 30,000 Starlink satellites in addition to the 12,000 it already planned, the company will by itself be responsible for about a fivefold increase in the number of spacecraft launched by humanity.

Here is SpaceX’s full statement:

“As demand escalates for fast, reliable internet around the world, especially for those where connectivity is non-existent, too expensive or unreliable, SpaceX is taking steps to responsibly scale Starlink’s total network capacity and data density to meet the growth in users’ anticipated needs.”
 

Source: https://spacenews.com/spacex-submits-paperwork-for-30000-more-starlink-satellites

Online Orionid

  • Weteran
  • *****
  • Wiadomości: 14825
  • Very easy - Harrison Schmitt
Successful launch continues deployment of SpaceX’s Starlink network
November 11, 2019 Stephen Clark [SFN]


SpaceX’s Falcon 9 rocket took off from Cape Canaveral at 9:56 a.m. EST (1456 GMT) Monday. Credit: Steven Young/Spaceflight Now

Sixty upgraded satellites for SpaceX’s Starlink broadband network rocketed into orbit Monday from Florida’s Space Coast, debuting performance enhancements and notching new firsts in SpaceX’s list of rocket reuse accomplishments.

SpaceX’s second batch of Starlink satellites joined 60 previous broadband-beaming spacecraft in orbit after deployment from a Falcon 9 rocket Monday, adding to a network that may eventually include thousands of satellites broadcasting high-speed Internet signals from space.

The 229-foot-tall (70-meter) Falcon 9 climbed away from Cape Canaveral’s Complex 40 launch pad at 9:56 a.m. EST (1456 GMT), turned toward the northeast and soared through scattered clouds on a gorgeous Veterans Day morning.

Nine kerosene-fueled Merlin 1D engines powered the Falcon 9 with 1.7 million pounds of thrust, sending the rocket into the sky with a thundering sendoff. It was the first launch to take off from a Cape Canaveral launch pad since Aug. 22, and SpaceX’s first satellite launch since Aug. 6.

The Falcon 9’s first stage shut down and detached from the rocket’s second stage around two-and-a-half minutes into the flight. Moments later, the Falcon 9’s second stage lit its single Merlin powerplant to propel itself into orbit with the Starlink payloads, then the rocket’s nose cone opened and fell away, revealing the Starlink satellites after transiting through the thick, lower layers of the atmosphere.

The first stage booster returned to a propulsive landing on SpaceX’s drone ship “Of Course I Still Love You” holding position around 400 miles (650 kilometers) downrange from Cape Canaveral in the Atlantic Ocean, roughly due east of Charleston, South Carolina. The rocket completed its fourth mission, following three previous launches and landings — two last year, and one in February that helped loft into space an Indonesian communications satellite and the Israeli Beresheet moon lander.


Cytuj
Spaceflight Now@SpaceflightNow 4:23 PM - Nov 11, 2019
Here’s a replay of the Falcon 9’s first stage coming in for landing this morning on SpaceX’s drone ship “Of Course I Still Love You” in the Atlantic Ocean east of Charleston, South Carolina. Continuing coverage: https://spaceflightnow.com/2019/11/11/falcon-9-starlink-1-mission-status-center-2/
Twitter


Monday’s launch was the first time SpaceX flew a Falcon 9 booster on a fourth mission. It also marked another first for SpaceX, which demonstrated its capability to reuse a payload fairing recovered from a previous launch.

The bulbous payload shroud protects satellites during the first few minutes of flight, then drops away from the rocket in two halves. The fairing halves flown Monday originally launched on a Falcon Heavy mission April 11, then parachuted into the Atlantic Ocean, where SpaceX teams pulled them from the sea for inspections, refurbishment and reuse.

SpaceX planned to attempt to catch both fairing halves with two specially-outfitted boats Monday. But managers ordered the ships to port due to concerns about rough seas.

SpaceX now has two fairing recovery ships in its fleet, both equipped with giant nets to catch composite fairing halves as they gently fall to the sea under parachutes. The fairings also carry cold gas thrusters to control their descent.

On previous missions, SpaceX has tried to catch one fairing half using a single boat. The company successfully caught one piece of the fairing for the first time after a July 25 launch of a Falcon Heavy rocket.

Pursuing the prime objective of Monday’s mission, the Falcon 9’s second stage engine switched off about nine minutes after launch, and the rocket coasted over Europe and the Middle East before reigniting its engine at around 10:41 a.m. EST (1541 GMT) to circularize its orbit. The Falcon 9 aimed for an altitude of around 174 miles (280 kilometers) for deployment of the Starlink satellites, and a member of SpaceX’s launch team confirmed the rocket achieved an on-target orbit.

The Falcon 9 sent commands at 10:56 a.m. EST (1546 GMT) to release retention pins holding the Starlink satellites to the launcher, and live video from a camera on-board the rocket showed the 60 flat-panel spacecraft receding in the blackness of space.



Sixty Starlink satellites separated from the Falcon 9 rocket about one hour after launch Monday. The spacecraft deployed in one piece, then will disperse over the coming hours and days. Credit: SpaceX

The satellites, but at a SpaceX facility in Redmond, Washington, are designed to gradually disperse over the coming hours and days. Ion thrusters fed by krypton fuel will maneuver the satellites into operational 341-mile-high (550-kilometer) orbits inclined 53 degrees to the equator.

SpaceX says 1,440 of the satellites are needed to provide Internet service over the “populated world,” a service level the company says could be achieved after 24 launches.

The Starlink network could offer service for northern parts of the United States and Canada after six launches, according to SpaceX.

SpaceX could launch thousands more Starlink satellites if merited by market demand. The Federal Communications Commission has authorized SpaceX to operate nearly 12,000 Starlink satellites broadcasting in Ku-band, Ka-band and V-band frequencies, with groups of spacecraft positioned at different altitudes and in various planes in low Earth orbit.

Documents filed with the International Telecommunication Union last month suggested SpaceX could add another 30,000 Starlink satellites to the network, growing its total size to 42,000 spacecraft.

The Starlink network is rapidly becoming a core business area for SpaceX, which is competing with companies like OneWeb and Amazon’s Project Kuiper to deploy fleets of thousands of small satellites in low Earth orbit to beam broadband Internet signals from space to users around the world.

Developers of the so-called “mega-constellations” in low Earth orbit say their networks offer key advantages over traditional satellite Internet architectures, which relay on satellites in higher orbits, where radio transmissions — even traveling at the speed of light — take longer to reach.



Artist’s illustration of the distribution of satellites in SpaceX’s Starlink network. Credit: SpaceX

SpaceX has launched more satellites than either of its chief competitors — Amazon has not yet launched any — and the spacecraft that lifted off Monday will introduce new capabilities to the Starlink network.

“Since the most recent launch of Starlink satellites in May, SpaceX has increased spectrum capacity for the end user through upgrades in design that maximize the use of both Ka- and Ku-bands,” SpaceX wrote in a press kit for Monday’s launch. “Additionally, components of each satellite are 100% demisable and will quickly burn up in Earth’s atmosphere at the end of their life cycle — a measure that exceeds all current safety standards.”

SpaceX said the new Starlink spacecraft design can provide a 400 percent increase in data throughout per satellite, and each satellite carries double the number of steerable phased array broadband beams than on earlier Starlink platforms.

The first 60 Starlink satellites, which launched May 23, carried only Ku-band antennas. At the time, SpaceX said 95 percent of the materials in each of the first 60 satellites would burn up in the atmosphere after their missions were complete.

Gwynne Shotwell, SpaceX’s president and chief operating officer, said last month that the company plans to begin launching Starlink spacecraft equipped with inter-satellite laser crosslinks some time mid-to-late next year.

Three of the 60 satellites launched in May have stopped communicating with ground controllers, but SpaceX officials say they are pleased with the overall performance of the initial block of Starlink spacecraft.

The U.S. Air Force is testing Internet connections between aircraft and SpaceX’s Starlink satellites to evaluate the network’s suitability for future military use, and Elon Musk, SpaceX’s founder and CEO, said he sent a tweet last month through a Starlink satellite.

“We still have ways to go from tweets to 4K cat videos, but we are on our way,” joked Lauren Lyons, a SpaceX engineer who hosted the company’s webcast of Monday’s launch.

Skywatchers with clear skies at twilight could see the Starlink satellites passing overhead in a train-like formation after Monday’s launch, similar to observations of the first 60 satellites following their launch in May.

The satellites reflected more sunlight than expected, creating a shimmering spectacle and sometimes flaring to be as bright as the brightest stars in the sky. The satellites appeared to dim over time, and observations became less frequent as they spread out in their orbital plane.

The bright satellites drew the ire of many astronomers, who worried the addition of thousands of similarly-bright satellites could interfere with scientific observations using ground-based telescopes.

The Royal Astronomical Society said in June that the large number of broadband satellites proposed by SpaceX, Amazon, OneWeb and Telesat “presents a challenge to ground-based astronomy.”

“The deployed networks could make it much harder to obtain images of the sky without the streaks associated with satellites, and thus compromise astronomical research,” the society said in a statement.

The National Radio Astronomy Observatory, funded by the National Science Foundation, said in May it was working with SpaceX to “jointly analyze and minimize any potential impacts” on astronomical observations caused by radio transmissions coming from the Starlink satellites.

“These discussions have been fruitful and are providing valuable guidelines that could be considered by other such systems as well,” the NRAO said in a statement. “To date, SpaceX has demonstrated their respect for our concerns and their support for astronomy.”

The NRAO said it continued to monitor, analyze and discuss the “evolving parameters” of the Starlink system. The NRAO identified several proposals under consideration, including exclusion zones and other mitigations around the National Science Foundation’s current and future radio astronomy facilities.

SpaceX says it is actively working with leading astronomy groups from around the world to make sure their work is not affected by the Starlink satellites. Engineers are taking steps to make the base of future Starlink satellites black to “help mitigate impacts on the astronomy community,” SpaceX said.

But SpaceX says satellites launched Monday do not incorporate the change.

SpaceX says it will adjust Starlink orbits should it be necessary for extremely sensitive space science observations, and the company has touted the ability of its next-generation Starship vehicle to send giant astronomical telescopes into space.

“We have also proactively reached out to leading astronomy groups from around the world to discuss the Starlink mission profile, scientifically assess the impacts on astronomy activities and evaluate any helpful mitigations moving forward,” a SpaceX official said.


Source: https://spaceflightnow.com/2019/11/11/successful-launch-continues-deployment-of-spacexs-starlink-network/

Online Orionid

  • Weteran
  • *****
  • Wiadomości: 14825
  • Very easy - Harrison Schmitt
SpaceX working on fix for Starlink satellites so they don’t disrupt astronomy
by Sandra Erwin — December 7, 2019 [SN]


Starlink launch Nov. 11, 2019. Credit: SpaceX

President and COO Gwynne Shotwell said the Starlink brightness problem caught the company by surprise

LOS ANGELES — One of the Starlink satellites in the next batch of 60 that SpaceX plans to launch in late December will be treated with a special coating designed to make the spacecraft less reflective and less likely to interfere with space observations, SpaceX president and chief operating officer Gwynne Shotwell said Dec. 6.

“We are going to get it done,” Shotwell said during a meeting with reporters at SpaceX’s headquarters in Hawthorne.

SpaceX already has deployed 120 satellites that beam high-speed internet, and thousands more will be launched over the next few years. Soon after the first launch in May, astronomers noted that the satellites were extremely bright, prompting concerns that the constellation will interfere with scientific research and views of the night sky.

Shotwell said the next batch has one satellite “where we put a coating on the bottom.” She noted that this is just an experiment and could not predict if it will work. “We’re do trial and error to figure out the best way to get this done,” said Shotwell.

Since reports first surfaced of Starlink satellites disrupting astronomers, the company has taken the problem seriously, Shotwell insisted. “We want to make sure we do the right thing to make sure little kids can look through their telescope,” she said. “Astronomy is one of the few things that gets little kids excited about space.”

When people look through their telescopes, “it’s cool for them to see a Starlink. But they should be looking at Saturn, at the moon. .. and not want to be interrupted.”

The coating that is being applied to one of the satellites in the third batch of Starlinks is just the first step toward finding a permanent solution as more satellites get deployed. Shotwell said the company plans to launch batches of 60 satellites every two to three weeks over the next year to build the constellation that by mid 2020 will be ready to provide global coverage.

Shotwell admitted that nobody in the company anticipated the problem when the satellites were first designed.

“No one thought of this,” she said. “We didn’t think of it. The astronomy community didn’t think of it.”

The experimental coating that would make the satellite less reflective could affect its performance, so that is something that will be examined, said Shotwell. “It definitely changes the performance of the satellite, thermally. It’ll be some trial and error but we’ll fix it.”


Source: https://spacenews.com/spacex-working-on-fix-for-starlink-satellites-so-they-dont-disrupt-astronomy/

Online Orionid

  • Weteran
  • *****
  • Wiadomości: 14825
  • Very easy - Harrison Schmitt
SpaceX becomes operator of world’s largest commercial satellite constellation with Starlink launch
by Caleb Henry — January 6, 2020 [SN]


SpaceX launched its third large batch of Starlink satellites Jan. 6 on a Falcon 9 rocket. Credit: SpaceX webcast.

WASHINGTON — SpaceX launched 60 of its own Starlink broadband satellites on a Falcon 9 rocket Jan. 6, becoming the operator of the world’s largest commercial satellite constellation.

The Falcon 9 rocket lifted off at 9:19 p.m. Eastern from Cape Canaveral, Florida, on SpaceX’s first launch of the year. The company’s 60 Starlink satellites, built to provide high-speed internet, separated from the rocket’s upper stage about an hour later.

SpaceX launched the satellites to a 290-kilometer orbit where the company will perform checkouts before raising them to their final 550-kilometer orbit.

SpaceX’s fairing-catcher ship “Ms. Tree” was unsuccessful in netting a fairing half after the launch.

The rocket’s first stage landed on the drone ship “Of Course I Still Love You” in the Atlantic Ocean, completing its fourth mission. SpaceX used this same booster to launch 60 Starlink satellites to low Earth orbit in May 2019, 10 Iridium Next satellites for Iridium in January 2019, and Telesat Canada’s Telstar 18 Vantage geostationary satellite in September 2018.

SpaceX has now launched 182 satellites for Starlink, counting two prototypes the company orbited nearly two years ago.

It’s not clear if all 182 Starlink satellites will be part of the constellation SpaceX expects to begin service with later this year. Some 10 satellites from SpaceX’s May 2019 Starlink launch never reached their final operational orbit, according to a Jan. 2 report from Jonathan McDowell, an astronomer at the Harvard-Smithsonian Center for Astrophysics who tracks satellite movements.

SpaceX said in July that three Starlink satellites had failed shortly after launch, and that another two healthy satellites would be intentionally deorbited as practice. The company did not respond to a SpaceNews inquiry Jan. 6 as to why 10 satellites have not reached their target orbit instead of five.

Regardless of if Starlink has 172 or 182 satellites, SpaceX still eclipses Planet, which has a constellation of 150 remote-sensing satellites, as the record holder for the world’s largest commercial satellite constellation.

SpaceX is deploying its first 1,584 satellites at 550 kilometers to accelerate service rollout and reduce the risk of creating orbital debris. At that altitude, any Starlink satellites that fail would naturally deorbit from atmospheric drag within 25 years — a guideline suggested by NASA and other space agencies.

One of the 60 satellites launched tonight was given a “darkening treatment” to make it less reflective. Shotwell told reporters last month that SpaceX is experimenting with different ways to make Starlink satellites less reflective so they don’t interfere with ground-based astronomy.

In December, the U.S. Federal Communications Commission approved a SpaceX request to fan out its Starlink satellites in more 550-kilometer orbits — a modification SpaceX says will enable the company to expand Starlink’s coverage to populated areas more rapidly.

SpaceX anticipated conducting up to six Starlink launches in 2019, but ended the year having done just two. Gwynne Shotwell, SpaceX’s president and chief operating officer, said in September that the company planned to do 24 Starlink launches in 2020, each presumably carrying 60 satellites.

SpaceX is building and launching up to 12,000 Starlink satellites, and has filed regulatory paperwork with the United Nations’ International Telecommunications Union for another 30,000 satellites.

Other companies are also planning large constellations of internet satellites, but none as large as SpaceX. OneWeb is planning a constellation of 1,980 satellites, Amazon is preparing for a 3,236-satellite constellation, and Telesat is designing a roughly 300-satellite broadband network.

SpaceX CEO Elon Musk said in May that Starlink would be “economically viable” at 1,000 satellites. He said reaching 12,000 satellites would be a “very successful outcome” for Starlink.


Source: https://spacenews.com/spacex-becomes-operator-of-worlds-largest-commercial-satellite-constellation-with-starlink-launch/

Online Orionid

  • Weteran
  • *****
  • Wiadomości: 14825
  • Very easy - Harrison Schmitt
SpaceX launches more Starlink satellites, tests design change for astronomers
January 7, 2020 Stephen Clark [SFN]


SpaceX’s Falcon 9 rocket streaks downrange to the northeast from Cape Canaveral Monday night with 60 Starlink satellites for the company’s planned global Internet network. Credit: SpaceX

Sixty more satellites for SpaceX’s Starlink global Internet network streaked into orbit Monday night from Cape Canaveral, including one spacecraft to test an experimental dark coating to address scientists’ concerns that the thousands of the quarter-ton, flat-panel satellites will impede astronomical observations.

The launch of 60 more spacecraft for the Starlink project, which SpaceX sees as a core business area in the coming years, makes the company the operator of the largest fleet of commercial satellites, surpassing the previous mark set by Planet, an operator of Earth-imaging nanosatellites.

SpaceX wants to begin limited Internet service through the Starlink network later this year, then expand to global service to beam Internet signals to consumers in far-flung locales outside the reach of terrestrial wired broadband connections. Users on airplanes, ships and the U.S. military could also be Starlink customers.

Blazing a similar trail to two previous Starlink satellite launches last year, a SpaceX Falcon 9 rocket lifted off from pad 40 at Cape Canaveral at 9:19:21 p.m. EST Monday (0219:21 GMT Tuesday) and turned on a northeasterly heading over the Atlantic Ocean.

Nine kerosene-fueled Merlin 1D engines on the base of the first stage powered the rocket off the launch pad with 1.7 million pounds of thrust.

After two-and-a-half minutes, the nine main engines shut down and the first stage separated to begin descent maneuvers toward a landing on SpaceX’s drone ship “Of Course I Still Love You” in the Atlantic Ocean.

The first stage — flying for the fourth time on Monday night’s mission — nailed its landing on the drone ship, marking the 48th time SpaceX has successfully landed a Falcon booster since the company’s first rocket recovery in 2015. An attempt to catch one half of the Falcon 9’s clamshell-like payload fairing in a net fastened to an ocean-going vessel was unsuccessful, SpaceX said.

The Falcon 9’s second stage ignited its Merlin engine two times to place the 60 Starlink satellites into an orbit with a target altitude of 180 miles (290 kilometers) and an inclination of 53 degrees to the equator. SpaceX confirmed the Falcon 9 injected the payloads close to the planned orbit.

Retention rods holding the 60 flat-panel Starlink spacecraft to the Falcon 9 rocket released at 10:20 p.m. EST (0320 GMT) to allow separation of the satellites.

An on-board camera view showed the 60 satellites deploy from the Falcon 9’s second stage. The Starlink relay stations were expected to begin dispersing in the coming days, while SpaceX control teams perform tests and activate the satellites’ krypton-fed ion thrusters to begin maneuvering toward their planned operating altitude of 341 miles (550 kilometers).

The launch Monday kicked off a brisk pace of launches by SpaceX planned for 2020.

Gwynne Shotwell, SpaceX’s president and chief operating officer, said last month the company could perform as many as 35 to 38 launches this year from three launch pads in Florida and California. That figure does not include potential test flights of SpaceX’s next-generation Starship vehicle.

The bulk of SpaceX’s missions in 2020 will add satellites to the company’s Starlink constellation of broadband satellites.

SpaceX plans to operate the initial block of 1,584 Starlink satellites in orbits 341 miles above Earth. The company has regulatory approval from the Federal Communications Commission to eventually field a fleet of up to 12,000 small Starlink broadband stations, and has hinted in additional regulatory filings that it could seek to operate up to 42,000 Starlink spacecraft.

In response to concerns from astronomers, Shotwell said one of the 60 satellites set for launch Monday will test a new less-reflective coating designed to reduce the brightness of the spacecraft. The first 120 satellites were brighter than expected, raising worries from scientists that thousands of Starlink craft could interfere with astronomical observations.

The satellites are especially bright soon after launch, when they are bunched together and flying at lower altitudes.



SpaceX’s Falcon 9 rocket lifts off Monday night. Credit: Steven Young/Spaceflight Now

“During orbit raise, the satellites are closely clustered together and their solar arrays are positioned in a special low-drag configuration, making the satellites appear visible from the ground just after deployment,” said Lauren Lyons, a SpaceX engineer who co-hosted the company’s webcast of Monday night’s launch. “However, once the satellites reach their operational altitude and begin on-station service, their orientation changes and the satellites become significantly less visible.

“While it’s really cool to catch a glimpse of those satellites from the ground, they can sometimes be a distraction for astronomers,” Lyons said. “So on this flight, Starlink is testing an experimental darkening treatment on one satellite in order to further reduce the light reflection off the satellites.”

SpaceX is seeking to strike a balance between astronomers’ concerns and the company’s ambitions for the Starlink network. Skywatchers will gauge the effectiveness of the new experimental coating to determine if it reduces the reflectivity of the satellite, and SpaceX wants to ensure the treatment does not impact the performance of the spacecraft.

“We also make satellite tracking data available to astronomers so they can better coordinate their observations with our satellites,” Lyons said. “These measures, along with our work with leading astronomy groups, will enable SpaceX to bring Internet access to underserved and unserved populations around the world without materially impacting the use of the night sky.”

SpaceX says it hopes to begin regional broadband service to Canada and the northern United States with the partially-complete Starlink constellation by the middle of this year, once it has launched 12 Starlink missions. Starlink service for Internet consumers worldwide will come after 24 launches, according to Shotwell.

“Twelve launches gets us connectivity with no gaps down to a latitude of roughly 25 degrees … And then 24 missions gets us global coverage with no data gaps,” Shotwell said last month. “So what’s preventing us from providing service? Getting the right number of satellites up in orbit. We will start offering service (mid-2020) because we have those 12 launches.”



Artist’s illustration of the distribution of satellites in SpaceX’s Starlink network. Credit: SpaceX
SpaceX has not announced pricing for the Starlink service.


“All I know is you will be far happier with the value of the Starlink service than you are with your current service,” Shotwell said in December. “You will, for sure, get way more bandwidth for the same price, or way more bandwidth for less … You’ll be far happier with this. The value will be far greater (than with current Internet service providers).”

She said SpaceX is building about seven Starlink satellites per day at a factory in Redmond, Washington. Low-volume production of SpaceX’s ground user terminals is also underway in California, Shotwell said.

SpaceX is still working out its strategy for commencing Starlink commercial services.

“Between now and June … we’re going to have to figure that out,” Shotwell said last month. “We will do presales like Tesla has done. The initial experience will be bumpy. We’ll have early customers be part of that journey with us. We’re not going to fib and say it’s going to be the best thing ever. When you get service, it’s going to be great. But it will be bumpy for a while.

The U.S. military has a contract with SpaceX to demonstrate the Starlink network’s ability to deliver data to the cockpit of airplanes, the first of what SpaceX hopes will be a lucrative business selling bandwidth to the Defense Department.

“I think we probably will mature as a provider, and it should not be bumpy, really in ’21. By ’21, I think we probably will have figured out most of the problems.”

SpaceX is gearing up for at least one more Starlink launch from Cape Canaveral using a Falcon 9 rocket later this month.

But first, the company’s Florida team will perform an in-flight test of the abort system the Crew Dragon commercial crew capsule on the ship’s final demonstration launch before NASA clears SpaceX to launch astronauts to the International Space Station.

The Crew Dragon in-flight abort test will take off from pad 39A at NASA’s Kennedy Space Center aboard a modified Falcon 9 rocket. Once it reaches the stratosphere, the crew capsule — flying without astronauts this time — will trigger its launch escape engines to propel itself away from the Falcon 9, verifying the ship’s ability to carry crews away from a failing rocket.


Source: https://spaceflightnow.com/2020/01/07/spacex-launches-more-starlink-satellites-tests-design-change-for-astronomers/

Online Orionid

  • Weteran
  • *****
  • Wiadomości: 14825
  • Very easy - Harrison Schmitt
SpaceX, astronomers working to address brightness of Starlink satellites
by Jeff Foust — January 8, 2020 [SN]


SpaceX says it's committed to reducing the brightness of its Starlink satellites, but while it works on that the company will continue to launch unmodified satellites. Credit: SpaceX

HONOLULU — SpaceX says it’s committed to working with the astronomy community to address the brightness of its Starlink satellites, but some astronomers remain concerned about the deleterious effect that system and other megaconstellations will have on their field.

One of the 60 satellites in the latest Starlink launch Jan. 6 featured an experimental coating intended to reduce its brightness. SpaceX said it will see in the coming weeks how well those coatings work, as well as study any effects they have on the performance of the satellite itself, before deciding how to move forward.

“Our level of brightness and visibility was a surprise to us,” said Patricia Cooper, vice president of satellite government affairs for SpaceX, during a Jan. 8 special session on the topic of megaconstellation effects on astronomy during the 235th Meeting of the American Astronomical Society (AAS) here. SpaceX President Gwynne Shotwell also said last month that SpaceX was surprised by the brightness of the satellites.

Cooper said that brightness is affected by several issues. The Starlink satellites initially appear bright when released in a lower parking orbit, and the configuration of each satellites’ single large solar array when raising its orbit can also influence its brightness. Once in a final operating orbit of 550 kilometers, the spacecraft brightness decreases to a visual magnitude of about five, making them visible to the naked eye only in darker night skies.

One challenge, she said, is the unique design of the satellite made it difficult to determine exactly what causes the spacecraft to reflect so much light. “It turns out, we think, that surfaces that scatter light, or reflect light diffusely, are also significant contributors,” she said. That led to the testing of surfaces on the experimental satellite, nicknamed “DarkSat” by some, to reduce that reflectivity.

While DarkSat is now in orbit, it will take some time to see how effective it is. Patrick Seitzer, an astronomer at the University of Michigan who is studying the effect of satellite constellations on optical astronomy, said at a later press conference that the satellite likely won’t reach its operational orbit until late February. “Then serious measurements can begin,” he said.

Cooper said that SpaceX would work quickly to reduce the brightness of its satellites, but didn’t give a specific timetable or state if other experimental satellites are in the works. In the meantime, the company will continue to launch the original design of Starlink satellites that are designed to be operational for five years, a plan that some astronomers at the meeting criticized.

“We don’t know yet if these mitigations are useful and effective,” she said. “We tend to work very quickly. We tend to test, learn and iterate.”

SpaceX has been meeting with a committee of the AAS to discuss the astronomy community’s concerns about Starlink and to examine ways to mitigate them. That work has included a half-dozen teleconferences and an in-person meeting during this AAS conference, said Jeff Hall, director of Lowell Observatory and chair of the AAS committee.

“We have not had to cajole SpaceX in any way. They’ve been very receptive and very proactive,” he said. Those discussions, he said, initially focused on SpaceX’s Starlink deployment plans, but more recently have been more just “keeping in touch” as SpaceX prepared to launch its experimental DarkSat.

Hall added that it was premature to discuss regulations regarding satellite brightness. “Regulation of the Wild West up there is necessary, but that is going to take a great deal of time to implement,” he said, while the problem posed by Starlink and other constellations is a near-term issue that needs to be addressed now.

Hall and other astronomers said that, like SpaceX, they were surprised by how bright the Starlink satellites appeared. “What surprised everyone — the astronomy community and SpaceX — was how bright their satellites are,” Seitzer said. “We knew these tens of thousands of megaconstellations were coming, but based on the sizes and shapes of things currently in orbit, I thought they’d be maybe eighth or ninth magnitude. We were not expecting second or third magnitude.”

Both astronomers and SpaceX said they hope, as an initial step to get the Starlink satellites dim enough to not be visible to the naked eye even in the darkest skies. The next step will be to figure out what else can be done to mitigate their effects on major observatories, specifically the Vera Rubin Observatory (formerly Large Synoptic Survey Telescope) under construction in Chile. Astronomers said that wide-field telescope was particularly threatened by Starlink and other megaconstellation satellites.

Hall said his AAS committee plans to start discussions with OneWeb later this month, shortly before the company begins full-scale deployment of its constellation. Six OneWeb demonstration satellites are currently in orbit, at altitudes higher than SpaceX. Seitzer said the satellites, at about eighth magnitude, are too dim to be seen by the naked eye, but pose in some cases greater concerns to professional astronomers than Starlink satellites because, at their altitudes, they may be visible all night during the summer, rather than just around sunset and sunrise.

With SpaceX seeking to deploy up to 1,500 Starlink satellites in 2020 alone, and with OneWeb and other constellations under development, astronomers warned this was a major issue to them. “The issue of megaconstellations and astronomy is a serious issue,” Seitzer said. “We have a very short time to deal with this issue.”


Source: https://spacenews.com/spacex-astronomers-working-to-address-brightness-of-starlink-satellites/

Online Orionid

  • Weteran
  • *****
  • Wiadomości: 14825
  • Very easy - Harrison Schmitt
SpaceX boosts 60 more Starlink satellites into orbit after weather delays
January 29, 2020 Stephen Clark [SFN]


A Falcon 9 rocket lifted off at 9:06:49 a.m. EST (1406:49 GMT) Wednesday with 60 Starlink Internet satellites. Credit: Stephen Clark / Spaceflight Now

After waiting more than a week for good weather, SpaceX launched a Falcon 9 rocket Wednesday from Cape Canaveral with 60 more satellites for the company’s Starlink Internet network, continuing to build out a fleet of fleet of orbiting broadband relay stations that could eventually number in the thousands.

The 229-foot-tall (70-meter) Falcon 9 rocket fired up at 9:06:49 a.m. EST (1406:49 GMT) Wednesday and climbed away from from Cape Canaveral’s Complex 40 launch pad. An incandescent flame from the rocket’s nine Merlin 1D main engines — collectively generating 1.7 million pounds of thrust — trailed more than 20 stories behind the launcher.

A roar from the Falcon 9’s engines reached spectators a few seconds later as the rocket arced toward the northeast into clear skies over Florida’s Space Coast.

The liftoff Wednesday came after a series of weather delays since last week. After performing a standard pre-launch test-firing of the rocket, SpaceX pushed back the launch from Jan. 21 to Jan. 24, then to Monday, Jan. 27, to wait for improved weather conditions in the Atlantic Ocean, where SpaceX stationed ships to retrieve the first stage and payload fairing from the Falcon 9 rocket.

SpaceX scrubbed a launch attempt Monday due to strong upper level winds, then bypassed a launch opportunity Tuesday, again wait for better weather in the downrange recovery area.

Weather conditions at Cape Canaveral appeared ideal for a launch Wednesday, and SpaceX’s 80th Falcon 9 flight put on a spectacular show.

Two-and-a-half minutes after liftoff, the rocket’s first stage shut down its engines and dropped away from the Falcon 9’s second stage. Seconds later, the upper stage’s single Merlin engine — modified with an enlarged nozzle for better performance in space — ignited to accelerate the 60 Starlink satellites into orbit.

The Falcon 9 jettisoned its clamshell-like payload fairing nearly three-and-a-half minutes into the mission.

Flying tail first, the rocket’s first stage booster reignited three of its nine engines to guide it toward SpaceX’s drone ship “Of Course I Still Love You” positioned around 400 miles (630 kilometers) northeast of Cape Canaveral. A final landing burn using the center engine slowed the booster for a controlled vertical touchdown on the football field-sized barge, marking the 49th time SpaceX has recovered one of its rockets intact.


Cytuj
Spaceflight Now @SpaceflightNow 4:25 PM - Jan 29, 2020

Here’s a replay of the Falcon 9 rocket’s first stage landing on a SpaceX vessel in the Atlantic Ocean roughly 400 miles northeast of Cape Canaveral this morning. This was the third flight of this particular booster from three different launch pads. https://spaceflightnow.com/2020/01/27/falcon-9-starlink-3-mission-status-center-2/

Twitter

The booster flown Wednesday was making its third trip to space, following successful launches and landings in March 2019 and June 2019 on flights carrying SpaceX’s Crew Dragon spacecraft and Canada’s Radarsat Constellation Mission. With Wednesday’s mission, the booster has launched from all three of SpaceX’s active launch pads in Florida and California.

The two halves of the Falcon 9’s payload shroud used cold gas thrusters to maneuver into the proper orientation for descent, then unfurled parafoils for a gentle fall toward the Atlantic Ocean. SpaceX’s two fast-moving fairing recovery boats — named “Ms. Tree and “Ms. Chief” — tried to catch both halves of the Falcon 9’s aerodynamic fairing.

SpaceX confirmed Ms. Tree caught one side of the shroud in a giant net. Ms. Chief, equipped with a similar net, failed to snag the other half of the fairing before it fell into the sea, but teams were expected to pull the hardware from the ocean for inspections and refurbishment.



SpaceX’s recovery boat “Ms. Tree” caught one half of the Falcon 9 rocket’s two-piece payload fairing after Wednesday’s launch. Credit: SpaceX

While SpaceX’s teams in the Atlantic were busy recovering pieces of the Falcon 9 rocket for reuse, the launcher’s upper stage — which is not reusable — fired its engine two times to place the 60 Starlink satellites into a targeted 180-mile-high (290-kilometer) orbit inclined 53 degrees to the equator.

SpaceX said the rocket did its job placing the satellites into the proper orbit, and live video from the Falcon 9’s second stage showed the 60 flat-panel satellites separating from the launch vehicle as it flew south of Australia about one hour after liftoff from Cape Canaveral.

The spacecraft were expected to extend their power-generating solar panels, and krypton ion thrusters on each satellite will begin raising their orbits to an altitude of around 341 miles (550 kilometers), where SpaceX intends to operate its first 1,584 Starlink platforms to provide worldwide Internet service.



Cytuj
Spaceflight Now @SpaceflightNow 4:17 PM - Jan 29, 2020
Here’s a video of SpaceX’s 60 latest Starlink Internet satellites separating from a Falcon 9 rocket as it flew in orbit south of Australia. https://spaceflightnow.com/2020/01/27/falcon-9-starlink-3-mission-status-center-2/
Twitter

The Starlink satellites, built at a SpaceX facility in Redmond, Washington, filled the volume of the Falcon 9’s payload fairing. Each satellite weighs around 573 pounds, or 260 kilograms, and the Starlink craft stacked together form the heaviest payload SpaceX has ever launched.

With Wednesday’s launch, SpaceX has deployed 240 Starlink satellites on four dedicated missions since last May. That makes SpaceX the owner of the world’s largest fleet of commercial satellites.

SpaceX, founded by billionaire Elon Musk, has regulatory approval from the Federal Communications Commission to eventually field a fleet of up to 12,000 small Starlink broadband stations. But SpaceX has said the size of the Starlink fleet will grow with demand after the company launches its initial block of 1,584 satellites.

SpaceX says 24 launches are needed to provide global broadband service through the Starlink service. But the company could provide an interim level of service over parts of the Earth later this year, once SpaceX has launched around 720 satellites on 12 Falcon 9 flights.

Gwynne Shotwell, SpaceX’s president and chief operating officer, told reporters in December that the Redmond factory was producing as many as seven satellites per day.

“Because Starlink satellites fly in a global constellation, we can bring high-speed Internet to places that previously had terrible service or no service at all,” said Lauren Lyons, a SpaceX engineer who provided commentary on SpaceX’s webcast of Wednesday’s mission. “Some of the most exciting opportunities for Starlink are rural or remote locations where traditional fiber or cable just isn’t practical.”

Cruise ships, airplanes and the U.S. military are also likely customers of Starlink services.

SpaceX has not announced a price for the Starlink service, or downlink and uplink speeds customers can expect through the network.

“Building a constellation that can provide this level of service is incredibly challenging, but we are making steady progress toward that goal with every Starlink launch,” Lyons said.



A view of the 60 Starlink satellites stacked before Wednesday’s launch. Credit: SpaceX

Scientists have raised concerns that thousands of Starlink satellites in low Earth orbit could interfere with astronomical observations. The Starlink spacecraft launched last year were more visible from the ground than predicted, prompting criticism from some scientists and amateur astronomers.

The satellites are especially bright soon after launch, when they are bunched together and flying at lower altitudes.

SpaceX debuted an experimental darkening treatment on one of the Starlink satellites launched Jan. 6, but none of the 60 satellites delivered to orbit Wednesday have the darker coating, which is aimed at minimizing reflectivity of sunlight down to the ground.

“It takes a few weeks for those satellites to reach their final orbit destination, so we don’t have the results of that DarkSat experiment just yet, but we’ll be sure to share what we’ve learned as the data becomes available,” Lyons said.

With Wednesday’s launch, SpaceX has sent 120 Starlink satellites into orbit on two Falcon 9 missions just this month. At least one Starlink launch with approximately 60 additional satellites is scheduled in February on another Falcon 9 rocket.

More than half of SpaceX’s 35 to 38  launches scheduled in 2020 will carry Starlink satellites, Shotwell said last month.


Source: https://spaceflightnow.com/2020/01/29/spacex-boosts-60-more-starlink-satellites-into-orbit-after-weather-delays/

Polskie Forum Astronautyczne