It impacted Jupiter's atmosphere on the 7th December 1995 at a speed of 48 km/s. The Galileo probe was a 1.3 metre across probe which was released from the Galileo Orbiter in July of 1995. Galileo Probe Enters Jupiter's atmosphere This resulted in another first - the detection of a moon orbiting about an asteroid - named Dactyl (after the mythological dactyls who inhabited Mount Ida on the island of Crete) at 1.4km radius. On its journey to Jupiter, Galileo used 34kg of fuel to adjust its trajectory to come within 2390km of asteroid 243 Ida (named after Ida who was a nymph of Crete who raised the Greek god Zeus) of size 54 x 24 x 15km. Galileo passed within 1600km and sent back 57 images of this 12km diameter asteroid.
Asteroid 951 Gaspra (named after Gaspra, a Crimean town on the coast of the Black Sea) was encountered between earth sling shots and was the first asteroid to ever be visited by a spacecraft. The flight path involved 3 gravitational assists with 2 flybys of Earth and one of Venus. However ingenious fixes meant that the mission could continue with only minor losses of data.
Also later in the mission radiation affected some of the DTR's components preventing it from working. Unfortunately the tape recorders tape was also damaged when it got stuck in rewind for 15 hours. Improvements in data compression and the sensitivity of earth based receivers improved the data rate some what (1 kilobit per second) but meant that much more data had to be stored on the digital tape recorder and sent when time allowed - sometimes delaying data for months. After many and varied attempts to get the antenna deployed it was abandoned in favour of the low gain antenna which could only send data at a much lower rate (16 bits a second). The antenna was supposed to open like an umbrella, but due to lubricants drying out in storage several ribs failed to pop out. This meant that Galileo had to undertake a longer journey to Jupiter using Venus and Earth for gravity sling shots.Īn unforeseen side effect of the period in storage was that the orbiters high gain antenna (which could transmit data at 130 kilobits per second) failed to deploy properly. Due to the Challenger disaster, the spacecraft launch was delayed and then due to a new safety regime, carrying the Centaur rocket aboard a space shuttle was no longer allowed. It was designed to be launched on the space shuttle and accelerated on a direct trajectory to Jupiter using a Centaur-G booster rocket. The spacecraft had suffered several delays and changes to its planned delivery system. Galileo was launched on 18th October 1989 and comprised the Galileo Orbiter and the Galileo Probe, both destined for the Jupiter system. However the trails shown (which are with respect to the Sun) can be distracting so we recommend selecting Jupiter as the central object and fading out the orbit trails so that you can see Galileo’s orbits more clearly with respect to Jupiter. If you re-play the mission, you can see the Galileo's position as it orbits Jupiter. You can also wind the animation backwards in time to watch its launch and its flybys of Venus and the Earth, and insertion into orbit around Jupiter. The app above shows the last resting place of the Galileo Spacecraft right now - which is within Jupiter. Where is the Galileo Spacecraft right now?