25, 21, 20 lat temu...1) 17.02.1996 o 20:43:27 z wyrzutni LC-17B na Cape Canaveral wystartowała RN Delta 7925-8, która wyniosła do badania planetoidy 433 Eros sondę NEAR.
Po udanym starcie sonda została nazwana na cześć planetologa Eugene’a Shoemakera NEAR Shoemaker (Near Earth Asteroid Rendezvous – Shoemaker)
1996 February 17 - . 20:43 GMT - . Launch Site: Cape Canaveral. Launch Complex: Cape Canaveral LC17B. LV Family: Thor. Launch Vehicle: Delta 7925-8.
NEAR - . Payload: Discovery 1. Mass: 818 kg (1,803 lb). Nation: USA. Agency: NASA Greenbelt. Program: Discovery series. Class: Asteroids. Type: Asteroid probe. Spacecraft: NEAR. Decay Date: 2001-02-12 . USAF Sat Cat: 23784 . COSPAR: 1996-008A.
Near Earth Asteroid Rendezvous (NEAR) mission was the first of NASA's Discovery missions, a series of small-scale spacecraft designed to proceed from development to flight in under three years for a cost of less than $150 million. The spacecraft's mission was to rendezvous with and achieve orbit around the asteroid Eros in January 1999, and study the asteroid for one year. However as it flew by the Earth on 23 January 1998, a problem caused an abort of the first encounter burn. The mission had to be rescoped for a later encounter but successfully entered orbit around Eros on Valentine's Day 2000 and ended the mission by gently landing on its surface on 12 February 2001.
http://www.astronautix.com/f/february17.htmlNEAR Shoemaker launched by a Delta 2 rocket, February 17, 1996https://twitter.com/ron_eisele/status/175856212423683287617 February 1996. 20.43.27 UTC/GMT. Launch of the Near Earth Asteroid Rendezvous from Cape Canaveral Air Force Station LC-17 aboard a three-stage McDonnell Douglas Delta II rocket (7925-B). Unmanned spacecraft on a mission to study several near-Earth asteroids.
Asteroid Visitor, Asteroid Orbiter, Asteroid Lander: 20 Years Since the Launch of NEAR Shoemakerby Ben Evans January 17, 2016
Asteroid 433 Eros, visited by the Near-Earth Asteroid Rendezvous (NEAR)-Shoemaker during 1998-2001. Photo Credit: NASATwenty years ago, today, on 17 February 1996, NASA’s Near-Earth Asteroid Rendezvous (NEAR)—a name later adjusted to honor the planetary scientist Gene Shoemaker—rocketed away from Launch Complex (LC)-17B at Cape Canaveral Air Force Station, Fla., aboard a venerable Delta II booster. As its name implied, the octagonal-prism-shaped spacecraft sought to enhance our understanding of the nature of near-Earth asteroids, aiming to rendezvous and enter orbit around 433 Eros. In the days before launch, NASA noted that it would not only represent humanity’s first long-term, close-range inspection of the surface composition and physical properties of an asteroid, but would also mark the smallest Solar System object yet orbited by a spacecraft. By the time NEAR-Shoemaker’s mission ended on 12 February 2001, it had not only physically landed on Eros’ surface, but had also returned a wealth of data from a flyby of another asteroid, Mathilde.
https://www.americaspace.com/2016/02/17/asteroid-visitor-asteroid-orbiter-asteroid-lander-20-years-since-the-launch-of-near-shoemaker/2)
NEAR na orbicie wokół Erosa ! 14.02. 2000 sonda NEAR wykonała manewr satelizacji na orbicie wokół planetoidy (433) Eros. W wyniku pracy
silnika (15:33:06-15:34:03) sonda osiągnęła orbitę o wysokości około 330 km nad powierzchnią Erosa.
Ostatnio o locie NEAR-a pisałem
08.02. Strona internetowa misji jest
tutaj.
http://lk.astronautilus.pl/n000201.htm#13USA: NASA SPACE CRAFT ORBITS EROS ASTEROID2328 wyświetleń•21 lip 2015
In a First, a Spacecraft Is Orbiting an AsteroidFebruary 15, 2000 By WARREN E. LEARY
LAUREL, Md., Feb. 14 -- With a nudge from its small rockets, the spacecraft NEAR gently embraced the asteroid Eros today to become the first man-made object to orbit such a space rock.
In a circuitous four-year journey through the inner solar system, which included a swing by Earth for a gravity boost and a failed effort to link up with Eros last year, the spacecraft became the first artificial satellite to circle an asteroid.NASA/JPL/JHUAPL The spacecraft NEAR sent back this photograph of its rendezvous yesterday with the asteroid Eros, 160 million miles from Earth.The robot spacecraft, called NEAR for Near Earth Asteroid Rendezvous, fired its thrusters for less than a minute to slow it enough to be captured by the weak gravity of the asteroid, a potato-shaped rock roughly twice the size of Manhattan. Because the computer-controlled maneuver took place 160 million miles from Earth, it took 20 minutes for news of its success to reach the Johns Hopkins University Applied Physics Laboratory here, which built the craft and controls the mission.
With confirmation of the orbit, happy scientists and engineers gave thumbs-up signs and slapped hands to celebrate their space first.
"We're orbiting around Eros," said Dr. Robert W. Farquhar, the mission director, "This is an historic day, a real milestone."
Dr. Andrew F. Cheng, the project scientist, said NEAR's success was more than a Valentine's Day gift. The spacecraft will orbit Eros for a year, slowing moving closer to the surface to make ever more precise measurements, and greatly increase the understanding of what scientists believe are remnants of the formation of the solar system some four billion years ago, Dr. Cheng said.
"Today may be Valentine's Day for most people, but it's Christmas Eve for me," Dr. Cheng said, "And all the presents are piled about, waiting to be opened."
Daniel S. Goldin, administrator of the National Aeronautics and Space Administration, which sponsored the $224 million mission, praised the Johns Hopkins team for persevering.
"This is tough stuff," Mr. Goldin said after NEAR went into orbit. "This is very hard work, and they've done a terrific job. But they still have a long way to go to declare mission success."
NEAR, loaded with six instruments to determine the mass, density, chemical composition and other characteristics of an asteroid, was launched from Cape Canaveral, Fla., on Feb. 17, 1996. Its target was 433 Eros, a large, rocky body named for the Greek god of love.
After circling back by Earth in January 1997, NEAR flew within 750 miles of another asteroid, Mathilde, in June 1997, to take measurements and 500 distant photographs. Unlike rocky Eros, Mathilde is a less dense aggregation of dust and materials rather than a solid piece.
Eros is called a near-Earth asteroid because its orbit crosses that of Earth and poses a potential collision danger. The elongated asteroid, measuring about 21 miles by 9 miles by 8 miles, came within 14 million miles of Earth in 1975.
Dr. Carl Pilcher, of NASA's Office of Space Science, said it was important to study different types of asteroids not only out of scientific curiosity but in self-defense. People may one day have to defend Earth against a deadly asteroid that could collide with the planet and destroy all life, he said. Such an asteroid is believed to have hit Earth 65 million years ago, setting off a chain of events that wiped out the dinosaurs.
"Understanding the physical characteristics of asteroids will be very important if we are ever called on to deflect one coming at the Earth," Dr. Pilcher said at a news conference.
NEAR was supposed to go into orbit around Eros last January, but its main engine misfired several weeks before, plunging the craft into a comatose "safe" mode while controllers tried to figure out the problem. NEAR missed its chance for an orbital maneuver and flew by Eros at a distance of 2,500 miles. But the spacecraft's controllers positioned the craft to chase Eros around the sun for a year to get another chance, which proved successful.
Dr. Joseph Veverka of Cornell University, head of the project's imaging team, said NEAR took its first major scientific reading the night before going into orbit. Using its infrared spectrometer, an instrument that tells chemical composition by analyzing light reflected from an object, the spacecraft took advantage of the sun's ideal position to map an entire face of the asteroid. "We're some very happy, very excited people," Dr. Veverka said.
Dr. Farquhar said that after scientists learned more about Eros's mass and orientation, they would slowly lower the spacecraft's orbit from about 300 miles down to about 30 miles in the next two months. Then the craft will climb back to 300 miles to compile images of the asteroid's entire surface.
When the mission is at its end next year, the scientists want NASA to consider allowing the craft to brush the asteroid's surface with one of its solar panels and then rise to photograph the resulting mark before crashing on the rocky body.https://archive.nytimes.com/www.nytimes.com/library/national/science/021500sci-near-eros.htmlNEAR Shoemaker's visit to the Valentine asteroid ErosBy Ben Evans | Published: Friday, February 12, 2021
Twenty years ago, just before Valentine’s Day, the plucky spacecraft NEAR Shoemaker managed to cuddle up close with an asteroid for the first time in history.NASA/JPL/JHUAPLAs hearts across the globe flutter this weekend for Valentine’s Day, spare a thought for a long-dead space probe, which for 20 years has sat in forlorn silence and solitude on a tiny peanut-shaped world at the fringe of the inner solar system.
NEAR Shoemaker — NASA’s Near-Earth Asteroid Rendezvous mission, a name later modified to honour planetary scientist Eugene Shoemaker — may now be far from Earthly companionship. But over the course of its life, it’s had frequent run-ins with the romantic holiday. The spacecraft launched during Valentine’s week in 1996, reached its destination during Valentine’s week in 2000, and it landed during Valentine’s week in 2001.
And as if that were not enough, the target of NEAR Shoemaker’s insatiable desire was none other than the stony asteroid Eros, a Staten Island-sized lump of primordial silicate-rich rubble named after the ancient Greek god of love. (...)
https://astronomy.com/news/2021/02/near-shoemaker-visits-the-valentine-asteroid-eros3 )16.02.2000 sonda zarejestrowała rotację asteroidy Eros.
https://twitter.com/airandspace/status/1626272765933133824Today in 2000, the NEAR Shoemaker spacecraft captured this rotation movie of the Eros asteroid. NEAR (Near Earth Asteroid Rendezvous) was the first spacecraft mission specifically designed to study an asteroid.
4)
Bliski przelot NEAR-a 20.10.2000 o 21:40 sonda NEAR-Shoemaker wykonała 46-sekundowy manewr OCM-15, w wyniku którego orbita wokół Erosa uzyskałą następujące parametry: hp=50 km, ha=52 km, i=133°. Kolejny 4-sekundowy manewr, OCM-16 został wykonany 25.10. o 22:10, a w jego wyniku sonda przeszła na najniższą z dotychczsowych orbitę: hp=19 km, ha=51 km, i=133°. W wyniku nieforemności kształtu planetoidy, minimalne zbliżenie do jej powierzchni nastąpiło 26.10. o 07:00 w odległości 5,3 km. Prędkość przelotu wynosiła około 6 m/s. Kolejna korekta, OCM-17, zostanie wykonana o 17:40, a nowa orbita uzyska parametry: hp=67 km, ha=198 km, i=144°.
Jeżeli wszystko pójdzie zgodnie z planem, to począwszy od 07.12. wykonana zostanie seria manewrów, która pozwoli osadzić próbnik na powierzchni Erosa dokładnie w rocznicę jego satelizacji - 14.02.2001. Ostatnio o locie sondy pisałem 05.10. Trzy obrazy Erosa uzyskane podczas przelotu:
- z dystansu 8 km (głaz w pobliżu środka obrazu ma około 25 m)
- z tego samego dystansu, lecz z innego kąta, widoczny jest większy obszar
- z dystansu 7 km (widoczny m. in. głaz o średnicy około 15 m).
Witryna internetowa sondy jest pod tym adresem.
http://lk.astronautilus.pl/n001016.htm#115)
Lądowanie na planetoidzie 12.02.2001 rozpoczęła się pierwsza próba
osadzenie sondy na powierzchni planetoidy. Manewr EMM-1 został wykonany o 15:32 i spowodował zejście sondy NEAR-Shoemaker z orbity, które trwało łącznie około 4,5 godziny.
Kolejny manewr, EMM-2 wykonany został o 19:16 i również zakończył się sukcesem, pomimo minimalnie mniejszego ciągu, niż wymagany (o ułamek procenta). O 19:27 wysokość wynosiła 5,4 km.
Manewr EMM-3 rozpoczął się o 19:31 i tym razem był minimalnie za duży, jednak nie wpłynęło to na przebieg zejścia. EMM-4 rozpoczął się o 19:47 i zakończył prawidłowo.
Ostatni manewr rozpoczął się o 19:59.
Jedno ze zdjęć powierzchni Erosa, wykonanych podczas lądowania.
Ostatnie pełne zdjęcie.
Ostatnie zdjęcie, częściowo przekazane na Ziemię.
Lądowanie nastąpiło o 20:02:10. Prędkość lądowania w
punkcie o współrzędnych 35°S, 81°E była rzędu 1 m/s.
Ostatni ostry obraz, o rozdzielczości około 10 cm otrzymano z wysokości 400 metrów.
Kontakt z sondą został utrzymany również po lądowaniu.
Szansa przetrwania lądowania przez sondę była oceniana na 1%.
Ostatnio o sondzie NEAR pisałem w
06.02..
Witryna internetowa sondy jest pod
tym adresem.
Uwaga: wszystkie momenty podawane są w czasie ERT (Earth Receiving Time), czyli w chwili odbioru sygnałów na Ziemi. Ze względu na dystans, dzielący Erosa i Ziemię, rzeczywiste czasy zajścia wydarzeń należy pomniejszyć o 17 minut i 35 sekund.
http://lk.astronautilus.pl/n010201.htm#08https://twitter.com/airandspace/status/1624808783380611073On #TDIH in 2001, Near Earth Asteroid Rendezvous (NEAR) Shoemaker became the first spacecraft to land on an asteroid. NEAR landed on Eros, sending back photos of the surface. #IdeasThatDefy
12 February 2001. The NEAR Shoemaker spacecraft touched down in the "saddle" region of 433 Eros becoming the first spacecraft to land on an asteroid.
https://x.com/ron_eisele/status/17567389474539851076)
Pierwsze dane z powierzchni Erosa W nocy z 18 na 19.02.2001 zaczęły na Ziemię napływać pierwsze dane naukowe z sondy
NEAR-Shoemaker. Są to wyniki pomiarów z magnetometru oraz ze spektrometru promieni X i gamma (XGRS - X-ray/Gamma Ray Spectrometer). Sonda nieoczekiwanie miękko wylądowała na
powierzchni Erosa
12.02.7)
Jeszcze 4 dni dla NEAR-a 23.02.2001 NASA zdecydowała się przedłużyć misję NEAR-a o dodatkowe cztery dni, to jest do końca lutego.
Tymczasem wyłączono magnetometr, ponieważ nie stwierdził on obecności mierzalnego pola magnetycznego
z orbity, podczas lądowania, jak i na samej powierzchni. Poprzednio o misji pisałem 19.02.
http://lk.astronautilus.pl/n010216.htm#068 )
NEAR zakończył misję 01.03.2001 o północy zakończono odbiór ostatnich danych z sondy NEAR-Shoemaker. Wkrótce po tym sonda,
która jako pierwsza weszła na orbitę wokół planetoidy i miękko na niej wylądowała została wyłączona.
Ostatnio o jej locie pisaliśmy
23.02.http://lk.astronautilus.pl/n010301.htm#01NEAR Shoemaker Weekly Report 2 Mar 2001By SpaceRef Editor March 2, 2001 Filed under NEAR mission at Johns Hopkins University, US
MISSION OPERATIONS:
NEAR Shoemaker Mission Operations was extremely busy during the final weeks of the program. End of Mission activities began in late January with a series of asteroid close flybys beginning January 24th and culminating on
January 28th. These flybys were immediately followed by two targeting maneuvers, Orbit Correction Maneuver 24 (OCM 24) on February 2nd and Orbit Correction Maneuver 25 (OCM 25) on February 6th. On February 12th, the spacecraft performed a spectacular descent and soft landing on the surface of 433 Eros. The precision of this propulsive maneuver sequence enabled an extension to the mission, allowing the XGRS Gamma Ray Spectrometer and
Magnetometer to perform in situ measurements. Finally, during the last track, on February 28th, the spacecraft was configured for hibernation mode.
https://spaceref.com/status-report/near-shoemaker-weekly-report-2-mar-2001/https://www.sciencedaily.com/releases/2001/03/010301073345.htmNEAR: The First Discovery Mission (Andrew Cheng)742 wyświetlenia•15 wrz 2011
https://solarsystem.nasa.gov/missions/near-shoemaker/in-depth/https://science.nasa.gov/mission/near-shoemaker/https://space.jhuapl.edu/destinations/missions/nearhttps://space.skyrocket.de/doc_sdat/near.htmhttps://en.wikipedia.org/wiki/NEAR_Shoemakerhttps://pl.wikipedia.org/wiki/NEAR_Shoemakerw
https://www.forum.kosmonauta.net/index.php?topic=1062.msg163#msg163