Subsurface water on Jupiter’s moon Europa is one place where humans plan to search for life. This artist’s concept shows a massive plume of underground water erupting from the moon’s surface. (Credit: NASA/ESA/K. Retherford/SWRI)

Jupiter’s moon Europa has an icy shell that conceals a liquid water ocean. Now, scientists have made the first direct measurement of water vapor in Europa’s atmosphere. It’s the best evidence yet for a water plume erupting from the moon’s surface.

The measuremen