Tag Archives: Jupiter

Galileo circling Jupiter

Today In History – October 18

Today to the date 24 years ago (in 1989), Space shuttle Atlantis launched Galileo, named after the astronomer Galileo Galilei. Its mission, to study Jupiter and its moons. It took the spacecraft a little over six years to reach Jupiter where it proved invaluable in understanding the largest planet in our solar system. Upon arrival, the craft – which consisted of an orbiter and entry probe – completed 35 orbits around Jupiter throughout a nearly eight-year mission and in September 2003 its mission ended with a controlled impact, disintegrating the spacecraft.

Some of the achievements of the mission include confirmation that the moon IO had extensive volcanic activity a hundred times greater than found on Earth, finding evidence that liquid oceans exist under Europa’s (the moon, not the continent!) icy surface, and establishing that Jupiter’s ring system is formed by dust kicked up as interplanetary meteoroids smash into the planet’s four small inner moons.

Talking about some impressive numbers, Jupiter – which is classed as a gas giant – its mass is nearly 318 times that of Earth’s and around 2.5 times that of the rest of the Solar System combined! The planet’s diameter is 11.2 times larger and its volume is 1321 times larger than Earth’s.