The Trip to Jupiter

Using the Shuttle to get to Low Earth Orbit
 
There had been a management decision to only use the shuttle to launch payloads into low earth orbit. The idea was to put Galileo on top of a rocket stage booster, ride these up in the back of the shuttle, and shoot off toward Jupiter. This was supposed to have happened in 1982 but the design of the rocket stage kept getting re- designed. You also have to think in terms of launch windows, times when the relative positions of Earth and Jupiter add together to optimize travel time. Finally Galileo was scheduled to go up on the next flight after ... Challenger. After the Challenger disaster, safety considerations dictated yet another redesign of the rocket stage and the long story short is that this was not going to have enough fuel to launch Galileo directly to Jupiter.


The long and winding road...
 
Galileo couldn't just fly straight off to Jupiter - it didn't have enough fuel-propellant for a direct flight. So they had to get pretty clever and use...that's right, Rocket Science!

The engineers dreamed up a fantastic voyage that had the spacecraft diving inward around Venus, catching the gravity assist wave there and zipping back to Earth, doing a two year loop-de-loop with a second Earth flyby and then swinging on out on the long final leg to Jupiter.

It was a long six year trip but Galileo sent back postcards along the way!


Postcard from Venus
 
Venus


Earth flyby
 
Earth


Asteroids
 
Asteroids


Comet Shoemaker-Levy
 
SL-9


Launching the Probe
 
The Probe into the Jovian upper atmosphere was the Greatest Rifle Shot in History. AKA "the shot heard around the Solar System."


Arrival Day
 
Arrival Day Timeline

On arrival day (December 7, 1995), the Orbiter skims 1,000 km above Io, picking up a gravity-assist, and then subsequently flies over the descending Probe so that the Probe can relay its data to the Orbiter. About an hour after the Relay, the 400N engine will burn for nearly an hour to place Galileo into Jupiter orbit.

GALILEO JUPITER ORBIT INSERTION QUICK LOOK
SCET = Spacecraft Event Time
JOI = Jupiter Orbit Insertion

  Jupiter close approach time (actual): 21:53:44 UTC/SCET
Jupiter close approach altitude (actual): 214,569 km
Io flyby altitude (actual): 892 km
Io close approach time: 17:45:58 UTC/SCET
JOI performance error: minus 0.1 percent
JOI burn duration: 49 minutes 00.4 seconds (planned 48.39)
Probe relay duration: 57.6 minutes (A channel); 46 minutes (B channel)
Probe relay check 1: 3:04 p.m. PST/ERT; confirmed: 3:10 p.m.
Probe depth at end of relay: 160 kilometers below cloud tops
Probe data playback (tape): Jan. 3 - April 15
symbol: Jan 03 - Jan 16
tape: Jan 25 - Feb 24 (partial)
tape: Mar 03 - Mar 11 (partial)
tape: Mar 26 - Apr 15
Perijove raise maneuver: March 14, 19:15 UTC-SCET (burn start)
Jupiter tour software load: 6 May to 22 June (exact dates TBD)
Ganymede 1 encounter: 27-Jun-1996


At Jupiter
 
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