Galileo's influence on modern science cannot be denied. He was one of the first to view objects in the sky using a telescope. He was the first to see the moons of Jupiter, the mountains on the moon, and sunspots. Fittingly, an unmanned spacecraft that was launched into orbit toward Jupiter on October 18, 1989, was named Galileo.It arrived at Jupiter on December 7, 1995, and was the first spacecraft to orbit the giant planet. It collected data that support the idea that liquid oceans exist under the icy surfaces of the Europa, Ganymede, and Callisto moons of Jupiter