Saturn's icy white moon Enceladus has given NASA scientists another clue that it could have the right conditions for life. They found that hydrogen molecules are spewing from the moon, which suggests hot spots on the world's hidden ocean.

The hydrogen has been found in icy water that periodically erupts through the moon's crust. And it may mean there are special underwater hot spots in this subsurface ocean, where frigid water is interacting with heated rocks. These hot spots could be perfect places for small organisms — bacteria, for instance — to thrive.

That's because similar hot spots are also found in the oceans of Earth and are home to lots of deep-sea creatures. They're known as hydrothermal vents; you can think of them as underwater geysers that form along ridges or openings in the sea floor. In these areas, the frigid ocean water mingles with Earth's piping hot magma, creating chemical reactions that produce different types of minerals and materials — including, yes, hydrogen gas — that rise up from the vents. And these chemical processes are major breeding grounds for microbial life here on Earth. Many experts think that some of the first forms of life on our planet formed around these vents; similar vents on Enceladus could be similarly abundant.