Jupiter moon Europa's chances of harboring life

Finding indicators of life on Jupiter's icy moon Europa will likely be more complicated than just taking snapshots of the world's surface, a new study suggests.

Why it matters: Europa is thought to be one of the best places to search for life in the solar system, with its subsurface ocean that could be habitable, but scientists are learning more about just how difficult it might be to actually find those signs of life.

What they found: The new study — published Monday in the journal Nature Astronomy — suggests parts of Europa's surface, down to about 12 inches below it, have been disrupted by impacts over tens of millions of years.

• It's possible this "impact gardening" could churn signs of life up to the surface where they would then be destroyed by radiation.
• “If we hope to find pristine, chemical biosignatures, we will have to look below the zone where impacts have been gardening,” Emily Costello, an author of the new study and researcher at the University of Hawai'i at Manoa, said in a NASA statement.
• Impact gardening on Europa has been studied before, but the new study makes use of specialized modeling that takes material raining back down onto the moon after an impact into account as well.

What to watch: In 2024, NASA is planning to launch a mission called Europa Clipper on flybys of the moon, so learning more about its potential habitability now will help focus that mission's goals and methods.

Go deeper: Where Europa's water lives