Europa: Remastered image may be prelude to a mission campaign.

Europa: NASA's Next Target in the Search for Life?

Europa: NASA's Next Target in the Search for Life?

Bad Astronomy
The entire universe in blog form
Nov. 22 2014 7:30 AM

The Art and Politics of an Icy Water World

Well, this is interesting: The folks at the Jet Propulsion Laboratory and SETI Institute have just released a remastered image of Jupiter’s moon Europa, and it’s breathtaking:

All these worlds are yours, including Europa. Attempt landings there.

Photo by NASA/JPL-Caltech/SETI Institute

That’s not even full-res; click it to see it in its splendor.


Europa is 3120 km (1930 miles) in diameter, a hair smaller than our own Moon. Unlike our Moon, which is rock through and through, Europa has a rocky core covered with water. And by water, I mean liquid water, an undersurface ocean covered with a kilometers-thick shell of ice. The water may be in a layer 100 km thick, and salty, making it a true ocean. In fact, it may have more liquid water than Earth does!

Phil Plait Phil Plait

Phil Plait writes Slate’s Bad Astronomy blog and is an astronomer, public speaker, science evangelizer, and author of Death From the Skies!  

The cracks you see are where ice floes fit together; the brighter areas are nearly pure water ice, but the red/orange regions are cracks, possibly where briny water has been squeezed to the surface, and materials in it chemically affected by the intense radiation environment surrounding Jupiter (caused by its very strong magnetic field interacting with material blasted out by volcanoes on Jupiter’s moon Io).

All of this has made Europa a prime target for exploration for a long time. I was going to write a bit about that, but then saw that JPL made a very informative video explaining it all.

That video is very well-done, and as I watched it I couldn’t help but think it felt like a trailer or promotional video for a new mission in the works. I know a lot of planetary astronomers have wanted to send a dedicated mission to the moon to investigate it far more thoroughly…


… and then I found that, due to the mid-term elections, Rep. John Culberson (R-Tex) is now head of the House's Commerce, Justice, and Science (CJS) appropriations subcommittee. He’s long been an advocate for a Europa mission.

It cannot be coincidence that this new image and video were put out now. The feeling I got while watching it, I suspect, is based on reality. I will not be surprised in the least if, for the next fiscal year budget, NASA asks for a Europa mission, including something as dramatic and unprecedented and as some hardware that can penetrate the ice and take a peek into Europa’s dark, briny depths.

I can’t say I’m opposed to that. There’s a lot of reasons to look around Europa as the video makes clear. You could argue the same for Enceladus, the icy moon of Saturn that has water geysers erupting from its south pole. In many ways Enceladus is a juicier target… but on average Saturn is twice as far from Earth as Jupiter, making the mission longer and more difficult. I figure go close first, learn the lessons, then push the distance boundaries more. As much as I’d like to see what’s under the ice of Enceladus, the shorter trip to Europa makes it an easier goal.

I’ve had my issues with Culberson about NASA, but, depending on how it’s done — extra funding for NASA so that no current or other future missions will get bled of funding, for starters — then an orbiter, lander, and sub-lander to Europa could very well be something I could get behind.

This is something I think NASA should be doing: Pushing the frontier, doing what only a national space agency can do. This would be a huge undertaking, and one that would fire up the public imagination like nothing before it since Apollo. I'd very much like to see that happen.