21 SEPTEMBER 2003 – SPACE PROBE GALILEO IS DESTROYED
It sounds like something out of a sci-fi movie – a space probe threatens to crash into one of Jupiter’s moons, possibly polluting it with bacteria. But this is no futuristic film. This is the true story behind the Galileo spacecraft.
The spacecraft – named after Italian astronomer Galileo Galilei, who discovered Jupiter’s four largest moons in 1610 – was launched into space in 1989 to learn more about the planet, its magnetic field and its many moons.
The craft, which consisted of an orbiter and an atmospheric probe, spent six years travelling from Earth, finally arriving at Jupiter in 1995.
On 7 December 1995 the probe reached Jupiter’s atmosphere, where it collected data for 57 minutes about the conditions there before it was destroyed by the heat and pressure of the planet’s atmosphere.
The orbiter, which had waited 80 million kilometres away, orbited Jupiter 35 times in the eight years it was in service, collecting valuable data about the planet and its environment.
Galileo went out in a blaze of glory after US space agency Nasa plunged it into Jupiter’s atmosphere on 21 September 2003.
The probe had run out of the fuel needed to steer it and scientists were worried that if they lost control of Galileo it might crash into Europa, one of Jupiter’s moons.
Scientists are almost certain that hidden beneath the icy surface of Europa is a saltwater ocean with about twice as much water as Earth’s global ocean and contaminating (see Word of the Week) the moon with microbes from Earth was a chance they did not want to take.