Vanguard (6,5in sat#1)

Launch data: Designation  F00002 / 57F01 Launch date  06 Dec 1957 - 16:44:35 UT Launch site  CC, LC18A Launch vehicle  Vanguard TV-3 Mission  test satellite Decay  06 Dec 1957

Spacecraft data: Prime contractor   Customer   Platform   Mass at launch  1,5 kg Dry Mass  1,36 kg Basic shape  sphere Dimension  dia 15,2 cm Solar array  6 solar cells Stabilization   DC power

Origins of the Vanguard program:

• In the spring of 1955, scientific interest in orbiting an artificial earth satellite for International Geophysical Year (1st July 1957 to 31 December 1958) was growing. Several launch vehicle proposals were developed for placing a U.S. satellite in orbit. The proposal chosen in August 1955 to be the U.S. satellite project for the IGY was the one offered by the Naval Research Laboratory (NRL), based on Milton W. Rosen's concept of a new launch vehicle combining the Viking first Stage, Aerobee second stage, and a new third stage. Rosen became technical director of the new project at NRL.
• The name "Vanguard" applied to both the first satellite series undertaken by the United States and to the launch vehicle developed to orbit the satellites. It was suggested by Rosen's wife, Josephine. Rosen forwarded the name to his NRL superiors, who approved it. The Chief of Naval Research approved the name 16 September 1956. The word denoted that which is "out ahead, in the forefront."

Mission details:

• Vanguard TV3 was the first U.S. attempt to launch a satellite into orbit around the Earth. It was a small satellite designed to test the launch capabilities of a three-stage launch vehicle and study the effects of the environment on a satellite and its systems in Earth orbit. It also was to be used to obtain geodetic measurements through orbit analysis.
  
• At launch the booster ignited and began to rise but about 2 seconds after liftoff, after rising about 1.3m, the Vanguard rocket lost thrust and began to settle back down to the launch pad. As it settled against the launch pad the fuel tanks ruptured and exploded, destroying the rocket and severely damaging the launch pad. The Vanguard satellite was thrown clear and landed on the ground a short distance away with its transmitters still sending out a beacon signal. The satellite was damaged, however, and could not be reused. It is now on display at the Smithsonian Air and Space Museum. The exact cause of the accident was never determined, presumably it was due to a fuel leak between the fuel tank and the rocket engine, possibly due to a loose connection in a fuel line or low fuel tank pressure allowing some of the burning fuel in the thrust chamber to leak back into the fuel tank.