65 lat temu, 17.03.1958 o 12:15:41 z wyrzutni LC 18A na Cape Canaveral RN Vanguard wyniosła na orbitę o parametrach: hp=654 km, ha=3869 km, i=34,25°, t=134,27 min. satelitę naukowego Vanguard 1.
Obiekt był aluminiową kulą o masie 1,47 kg i średnicy 15,2 cm [ale są rozbieżności w źródłach].
Satelita przeznaczony był do badania wpływu środowiska kosmicznego na systemy satelity.
Był również używany do uzyskiwania pomiarów geodezyjnych poprzez analizę orbity.
Pierwotnie zakładano, że satelita utrzyma się na orbicie przez ok. 2000 lat, ale zauważono, że ciśnienie promieniowania słonecznego i opór atmosferyczny podczas wysokiego poziomu aktywności słonecznej powodowały znaczne zaburzenia perygeum satelity, co spowodowało znaczny spadek jego oczekiwanego czasu pozostawania na orbicie do ok. 240 lat.
Vanguard 1C jest najstarszym obiektem pozostającym na orbicie okołoziemskiej.
Nadajnik zasilany bateryjnie przestał działać w czerwcu 1958 roku, gdy wyczerpały się baterie.
Nadajnik zasilany energią słoneczną działał do maja 1964 roku (kiedy w Quito w Ekwadorze odebrano ostatnie sygnały), po czym sondę śledzono optycznie z Ziemi (miała jasność od 12 do 15 magnitudo).
1958 March 17 - . 12:15 GMT - . Launch Site: Cape Canaveral. Launch Complex: Cape Canaveral LC18A. Launch Pad: LC18A. Launch Vehicle: Vanguard.
Vanguard 1 - . Payload: Vanguard 1C / Vanguard Test Satellite. Mass: 2.00 kg (4.40 lb). Nation: USA. Agency: USN. Program: Vanguard. Class: Technology. Type: Navigation technology satellite. Spacecraft: Vanguard 1. USAF Sat Cat: 5 . COSPAR: 1958-Beta-2. Apogee: 3,868 km (2,403 mi). Perigee: 654 km (406 mi). Inclination: 34.20 deg. Period: 133.20 min. Transmitted pear-shaped earth data. Life expectancy of perhaps a 1,000 years. The satellite had a mass of 1.6 kg and a diameter of 175 cm..
http://www.astronautix.com/m/march17.htmlThe spacecraft was a 1.36-kg aluminum sphere 15.2 cm in diameter, nearly identical to the later Vanguard 1. It contained a 10-mW, 108-MHz mercury-battery powered transmitter and a 5-mW, 108.03-MHz transmitter powered by six solar cells mounted on the body of the satellite.
http://www.astronautix.com/v/vanguard1.html(1/2) 65 lat temu Vanguard 1, pierwszy sztuczny obiekt kosmiczny wyposażony w ogniwa fotowoltaiczne jako źródła energii elektrycznej, został wystrzelony na orbitę. W sumie satelita został wyposażony w 6 par krzemowych ogniw fotowoltaicznych o sprawności 8% generujących 1 W.
(2/2) Wykorzystanie ogniw fotowoltaicznych było już rozważane we wnioskach z 1951 r. jako część operacji Lunchbox. W 1955 r. zostały one ostatecznie zakotwiczone w propozycji, także dzięki naleganiom prof. Van Allena i zapewnienie długoterminowych obserwacji. W tamtym czasie to nowe źródło nazywano konwerterem słonecznym.
https://twitter.com/Kosmo_Michal/status/1636630357469429762Launch of Vanguard 1 (TV-4)Vanguard: A Rocket for Science (Circa 1958, End is Missing)From the Archives: Oldest human-made object still in orbit around Earth was launched 65 years agoBY MERRIE MONTEAGUDO MARCH 17, 2023 4:50 AM PT
“I want to emphasize that we put tow objects into orbit with a total weight in excess of 50 pounds,” Dr. John P. Hagen, chief of the Vanguard Project, told reporters in Washington.
The second object is the third stage rocket which carried the Vanguard, he said.
Hagen also announced that the Navy will “try very soon” to put into orbit the regular 21 1/2-inch scientific satellite, which originally was scheduled for launching by March 1.
Hagen said that Vanguard I, which went into orbit this morning, will circle the earth “for a great many years—certainly five or 10 years.”
https://www.sandiegouniontribune.com/news/local-history/story/2023-03-17/from-the-archives-vanquard-i65 years ago, Vanguard 1, the second American artificial satellite17/03/2023 12:29 | Philippe Varnoteaux (Automatic translation from French) | Source : Air&Cosmos1037 mots
Finally Successful
On March 17, the third attempt, Vanguard TV4, was finally successful and was hailed by the media. Thus, Le Républicain Lorrain announces " VANGUARD I, US Navy satellite finally orbits in space ", stating that it " has joined Explorer I and Sputnik II ". Similarly, Le Parisien libéré of March 18 reports to its readers that " PAMPLEMOUSSE HAS FINALLY TAKEN THE START " Placed in an elliptical orbit of 654 km perigee and 3 969 km apogee, with an inclination of 34.25°, the satellite, named Vanguard 1, becomes the fourth satellite in history, the second American. Vanguard has a mercury battery pack, a telemetry transmitter, a Minitrack beacon transmitter powered by solar cells mounted on the satellite's body, with six 30-cm-long spring-loaded aluminum alloy antennas protruding from the sphere. Vanguard also has a system that measures the interior temperature of the satellite to track the effectiveness of the thermal protection.
As for the scientific results, the on-board transmitters show that the Earth is slightly pear-shaped. The collected signals also allow determination of the total electron content between the satellite and some ground receiving stations. The solar cell-powered transmitter operated for more than 6 years, the signals gradually weakened and were last received at the Minitrack station in Quito, Ecuador, in May 1964.
https://aircosmosinternational.com/article/65-years-ago-vanguard-1-the-second-american-artificial-satellite-3705Project Vanguard became a part of NASA on its inception. One of the NASA Administrator's first official acts, however, was to delegate management of the project back to the Naval Research Laboratory. In actuality, therefore, no significant administrative change took place, and the members of the Vanguard field crew continued to put up their vehicles in accordance with the one-a-month schedule established shortly before the launching of Sputnik I. The success of TV-4 in March left them with a spare vehicle on their hands since the Martin Company had assembled and the hangar crew had checked out a backup vehicle, TV-4BU, against the possibility of failure. In accordance with a suggestion from the IGY committee, TV-4BU went back to GLM so that technicians at the Maryland plant could remove some of the test instrumentation and convert it into an SLV-a production satellite-launching, or mission, vehicle-for use in a later flight. Field preparations for the next scheduled launching proceeded in an atmosphere of some tension. Although the vehicle involved, TV-5, was only a test vehicle, its mission was to try to orbit the first fully instrumented Vanguard satellite, a 20-inch, 21.5-pound sphere. By the first week of April the first stage of TV-5 was on the firing stand at launch complex 18A, but the pad managers postponed erection of the upper stages because of facts brought out in a motion picture of the TV-4 launch. The film revealed that at the liftoff of that vehicle, the hydraulic disconnects had not separated smoothly. The belief was general that the pull-away stand that the Martin Company was in the process of completing would take care of this potentially troublesome situation. Unfortunately the new movable firing structure would not be ready for some time. For the scheduled flight test of TV-5, the only course open to the crew was to make some modifications in the old stationary structure and hope for the best.
https://history.nasa.gov/SP-4202.pdfhttps://nssdc.gsfc.nasa.gov/nmc/spacecraft/display.action?id=1958-002Bhttps://space.skyrocket.de/doc_sdat/vanguard-6in.htmhttps://en.wikipedia.org/wiki/Vanguard_1AA
https://www.forum.kosmonauta.net/index.php?topic=5289.msg182598#msg182598https://twitter.com/NASAhistory/status/1636736656337248258
Wątek: Kalendarium historycznych wydarzeń (Przeczytany 250544 razy)