Astronomers have discovered gaseous carbon dioxide in the atmosphere of Jupiter's second largest moon Callisto, suggesting the planet may have a much more complex carbon cycle than we thought. It suggests something. On Earth, the carbon cycle helps maintain a stable climate.
Callisto is one of the oldest objects in the solar system, forming around Jupiter about 4.5 billion years ago. It is also one of the most destroyed celestial bodies, with its surface covered in craters.
Source: www.newscientist.com