The gas giant planet's spots and swirls come from ... Volcanoes rage on Io's surface, earning it the title of the solar system's most volcanically active body. And scientists believe Europa ...

The layers of gases surrounding the surface of a planet make up what is ... They are sometimes called gas giants because they are large and made mostly of gases. Small amounts of rocky materials ...

It could be the core of a gas world like Jupiter, offering an unprecedented glimpse inside one of these giant planets ... a year is a mere 18 hours and its surface temperature is around 1,527C.