Vanguard (satellite)

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Image of Vanguard 1, the first successful satellite in the series
Vanguard 2
Vanguard 3

The Vanguard satellites were twelve NASA research and test satellites . In a total of eleven launches with the rocket of the same name , it was possible to bring two of the satellites into orbit . One satellite did not separate from the rocket upper stage and nine satellites were lost. The first satellite should after Sputnik 1 and  2 of the Soviet Union , the first satellite of America to be. The launch was televised across the US, with millions of people watching the launch fail.

history

By October 4, 1957, the United States and the rest of the western world believed that the first man-made Earth satellite would come from the United States. On that day, however, the Soviet Union launched the first satellite, Sputnik 1 , into space. Politicians, space experts and large parts of the population in the United States were shocked (see Sputnik shock ). The space experts there were also amazed at the mass of the Soviet satellite, namely 80 kg. That was about 53 times the mass of the spacecraft intended as the first satellite in the United States, the US Navy's Vanguard satellite . The United States government reported that the Vanguard satellite was ready for launch on a launch pad in Cape Canaveral . The announcement was based on an untruthful statement by James Hagerty , the White House press secretary . In his desperation to deliver a positive space travel announcement to the public, he had claimed that America would catch up with the Soviets in a few days because the Naval Research Laboratory would also launch a satellite with a Vanguard rocket. The Vanguard development group was completely taken aback by this announcement. The missile was far from being operational. Official satellite launches were not scheduled before the spring of 1958. For the beginning of December, however, it was planned to test the rocket for the first time with all three active stages. In the unlikely event that the test was successful, they wanted to put a tiny test satellite the size of a grapefruit into orbit. Much to their displeasure, the developers had to watch large numbers of reporters visiting Cape Canaveral to tell the audience about the launch of Vanguard 1 (ultimately called Vanguard TV3 ). Nowhere was the test character of the shooting mentioned, the success was assumed more or less as certain.

The launch of the Vanguard rocket was scheduled for December 6, 1957. At the time, television broadcast the first major nationwide live broadcast of a space event to millions of US households. The television show carved itself deeply into the US national memory. The rocket's engine fired and the Vanguard slowly lifted off about three feet from the launch pad. Then it fell back onto the ramp and detonated in a monstrous explosion in front of the entire nation. After all, the actual Vanguard 1 was not the first, but the fourth artificial earth satellite after Sputnik 1 and 2 and Explorer 1 . On March 17, 1958, pretty much exactly what the project team had originally planned, it was successfully put into orbit. Nevertheless, it achieved a first achievement: it was the first spacecraft to use solar cells for power supply. The connection to it was maintained for over six years and it is still in orbit today. This makes it the oldest man-made object in space. Its orbit is expected for about 240 years Template: future / in 5 yearsremain stable before moving into the Earth's atmosphere occurs .

In total, the NRL attempted eleven times between December 6, 1957 and September 18, 1959 to launch a Vanguard satellite into space. Only three of these starts were successful.

technology

The satellites were, as at that time all very small and light objects Vanguard - launcher could not absorb a lot of payload. They were mostly powered by batteries (and occasionally by additional solar cells ). The spacecraft were built by the Naval Research Laboratory and were used for research purposes.

List of starts

The satellites were all on the launcher Vanguard that on the sounding rocket Viking started based. It soon became apparent that the rocket was not fully developed. The take-offs were from Cape Canaveral AFS from launch pad 18A . The three successful spacecraft were given the designation Vanguard 1, 2 and 3. The failed missions were either declared as TV (Test Vehicle) (TV 3, TV 3 Backup) or designated as SLV (Satellite Launch Vehicle) .

satellite Start date ( UTC ) Dimensions orbit NSSDC ID Remarks
Vanguard TV3 December 6th, 1957, 4:44 pm 1.36 kg
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 Failure. Missile explodes 2 seconds after ignition on the launch pad
Vanguard TV3BU 02/05/1958 1.36 kg
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 Failure. Missile breaks after 58 seconds due to failure of attitude control
Vanguard 1 03/17/1958, 12:15 1.47 kg 654 km × 3969 km, 34.25 ° 1958-002A success
Vanguard TV5 04/29/1958, 02:53 9.75 kg
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 Failure. Failure of the electrical system of the second stage as a result of which the third stage did not ignite
Vanguard SLV1 May 28, 1958 , 3:46 am 10.0 kg
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 Failure. Attitude problems prevent it from reaching an orbit
Vanguard SLV2 06/26/1958, 5:00 am 10.0 kg
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 Failure. The second stage switches off again after eight seconds, the third stage does not ignite
Vanguard SLV3 09/26/1958, 3:38 pm 10.0 kg
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 Failure. Second stage did not perform well
Vanguard 2 02/17/1959, 3:55 pm 9.8 kg 559 km × 3320 km, 32.88 ° 1959-002A success
Vanguard SLV5 04/14/1959 , 02:49 10.3 kg
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 Failure. Position control of the second stage is lost when the first stage is separated
Vanguard Balloon ?
Vanguard SLV6 06/22/1959, 8:16 pm 10.3 kg
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 Failure. Loss of pressure in the tanks after ignition of the second stage
Vanguard 3 September 18, 1959 , 5:20 am 22.7 kg 512 km × 3744 km, 33.3 ° 1959-010A Partial success. Third stage did not separate from the satellite

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