NASA

Astronomers searching the night skies for signs of alien life have long set their sights on Jupiter’s icy moon Europa. The recent discovery of water vapor venting from Europa’s south pole has bolstered scientists’ theory that alien oceans lie beneath its frozen surface. Lorenz Roth, lead author of a December report that outlines the finding, said at the time that the vapor trail “strengthens Europa’s position as the top candidate for potential habitability.”

So it comes as no surprise that NASA hopes to probe the watery moon for signs of life. But the first leg of the mission was to Washington, D.C., where they ventured into cyberspace.

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On Tuesday, beloved science guy Bill Nye was joined by NASA’s chief scientist Ellen Stofan and Europa Study scientist Robert Pappalardo and the Planetary Society’s Casey Dreier in a Reddit Ask Me Anything (AMA) to answer questions about the moon.

When asked, “What caused Europa to form with so much water?” Pappalardo said:

“There was lots of water vapor in the solar system as it was forming. In the outer solar system, it was cold enough that lots of ice condensed (while in the inner solar system, it was too warm for that too happen). Thus, the moons of the outer planets were built from rock, metal, and ice, so they still contain much ice today. At Europa, tidal heating can melt some of this H2O to form a global subsurface ocean.”

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Stofan fielded the question, “What do you think would be the public reaction if life was found on Europa?”

“We are searching for life on Mars and hopefully soon on Europa — we are following the liquid water, which scientists think is critical for life. I think the public would be in awe over the ability to answer the question—are we alone, how similar is life on other worlds to life here on Earth, and how can we use that information to better understand ourselves!”

Other participants asked less relevant questions; a lot of people wanted to know how the scientists feel about the movie “Europa Report.” (“It was fun!” said Pappalardo). Many wanted to know what was on deck for Nye, while others made “science guy” jokes. A lot of “science guy” jokes.

NASA also announced that it is looking for proposals for scientific instruments that could be used on a possible Europa mission. According to NASA’s John Grunsfeld, the goal is to find instruments that “may provide a big leap in our search to answer the question: are we alone in the universe?”

Submissions are due by October 17. Roughly 20 proposals will be selected by April 2015. Those whose projects have been selected will receive some $25 million each to develop the instruments. Eight of those instruments will then be selected to go on a mission to the moon.

So overall, it wasn’t a bad day for Europa. And not such a bad day for stargazers, either.

Danielle Wiener-Bronner is a news reporter.