Space

NASA sizes up Europa landing to search for conditions for life

View 6 Images
Europa (Image: NASA/JPL/Ted Stryk)
How a Europa lander might look (Image: Europa Study Team)
Europa (Image: NASA/JPL/Ted Stryk)
An artist's impression of a lander's eye view from Europa's surface (Image: NASA/JPL-Caltech)
A composite image of Europa's surface captured from repeat flybys (Image: NASA/JPL-Caltech/University of Arizona)
A close-up composite image of ridges and cracks in Europa's surface captured by the Galileo spacecraft in 1997 (Image: NASA/JPL)
Europa's full disk captured from a range of 2 million kilometers (1.2 million miles) by Voyager 1 in 1979 (Image: NASA)
View gallery - 6 images

It's an icy inhospitable world, a little smaller than our own Moon: Europa. It's one of Jupiter's four largest satellites, the Galilean moons named after the polymath astronomer who discovered them in 1610. At the surface, the temperature never climbs above about -160º C (-256º F), yet it's thought that beneath the frozen epidermis there could be a liquid saltwater ocean. Were that the case, Europa would be about the best candidate for extraterrestrial life in the Solar System, albeit life in microbial form. That Europa could harbor life isn't news. That NASA is now considering landing a robot on Europa's surface is, and the agency has one or two ideas about what a robot should do when it gets there.

Like any robot designed for extraterrestrial exploration, a Europa lander would be armed to the teeth with a sensors and analytical equipment. But settling on the particular loadout really depends on what you want to find out. Every sensor and every gadget embodies a question to which we don't yet know the answer.

Europa's full disk captured from a range of 2 million kilometers (1.2 million miles) by Voyager 1 in 1979 (Image: NASA)

NASA has identified three priorities for a robot lander on Europa: discover the makeup of minerals and organic matter present on the moon; examine the geophysics of the ice and the ocean underneath; and determine how the geology looks (and therefore how it might have evolved) at a human scale on the surface. That may sound dry, but NASA says that this really boils down to looking at chemistry, water and energy, or in other words, the conditions necessary for life.

NASA has not announced a mission to soft-land a robot on Europa, but it has begun to put out its feelers. A new article by NASA scientists published in the peer-reviewed journal Astrobiology entitled Science Potential from a Europa Lander sets out these research goals in more detail, and speculates how they might be practically achieved. Though the theme of life runs throughout the paper (the word appears 33 times excluding the references section), the focus is very much on microbial natives and not, despite reports to the contrary, potential human habitation.

A close-up composite image of ridges and cracks in Europa's surface captured by the Galileo spacecraft in 1997 (Image: NASA/JPL)

One area of focus would be Europa's distinctive linear surface cracks. These are believed to be caused by tidal forces, a result of Europa's eccentric orbit about Jupiter causing very high tides when the moon passes closest to the gas giant. It's thought that this process would generate the heat in the ocean necessary for simple life to survive there. NASA thinks the cracks could contain biological makers, molecules indicating the presence of organic life, which have come from the ocean.

Alas it's not as simple as rocketing a robot off to Europa. To ensure that such a mission would maximize returns requires that a "scientifically optimized" landing site is identified, and to do that, Europa's surface must be thoroughly surveilled. Thus far, the little we know and think about Europa is based on a handful of flybys by Voyager 2 in the 70s and the Galileo probe in the 90s.

"There is still a lot of preparation that is needed before we could land on Europa, but studies like these will help us focus on the technologies required to get us there, and on the data needed to help us scout out possible landing locations," said lead author Robert Pappalardo of NASA's Jet Propulsion Laboratory. "Europa is the most likely place in our solar system beyond Earth to have life today, and a landed mission would be the best way to search for signs of life."

Source: NASA

View gallery - 6 images
  • Facebook
  • Twitter
  • Flipboard
  • LinkedIn
9 comments
JimRD
Shouldn't NASA first figure out if there is life on Mars which is probably much more easily accessible than Europa? Or is this a ploy to drag out for the next generation the search for life incrementally so that every possible contractor and expense is used? - I know, too conspiratorially minded.
Slowburn
If looking for ET life going someplace with liquid water does sound practical.
Nairda
There are many hurdles to overcome for a successful completion of such a mission. First of all, the large magnetic fields on Europa that will mess with electronics and comms. Second the mechanism of drilling several km into the mantle. Third the extraction and analysis of a sample without contaminating the ecosystem.
They can start practicing in Antarctica on getting samples from lake Vostok using equipment that would be stowed on a rover.
Then they can repeat the exercise on the moon (to a lesser depth), which will test delivery of equipment to such a location, and deployment.
Meanwhile, comms and lab kit will develop to a point where we will immunize equipment against EM and shrink the vast amount of equipment required to do a decent job of analyzing the samples.
Slowburn
re; Nairda
1. Wrap the probe up in its own magnetic field. Use laser for communication. 2. You are boring through ice, and you have a nuclear heat source. 3. Being built in a clean room the probe is going to be pretty clean. Then put it in a plastic bag and irradiate the hell out of it with gamma rays.
There is no reason for the moon tests at all and while I wouldn't have a problem with with testing boring through ice with a warm nuclear powered probe in Antarctica it certainly is not worth the headaches dealing with the protests would bring. Besides the mechanics of testing it in a lab are not that difficult and if something does happen to go wrong it is much easier to retrieve.
MG127
@Narida they already tested some rovers,drills and under-water drones in antarctica. (since ~2005) the drone it self is 99.999% decontaminated and the surface will be heated up to over 100°C (heat drilling), this also ensures that the path behind the drill/drone will be closed after it automaticly.
they allready discovered some life down there in one of those lakes in antactica (not only bacteria)
JohnDavidHanna
If it is life it is dirt dumb. and cold. I don't see any reason to waste billions of tax dollars on thousands of employees that will wait decades to retire on my money. When they have figured out how to become productive ( moon mining settlements - comfortable ones - or asteroid mining ) They can use a little of that profit to drop a probe.
DSP
Stay away from Europa! Isn't that what the black monolith said?
Will Samuel
I just seen a B film titled Europa Report...and now i see this article. Yea if this project does come to life,NASA should have multiple bots on standby. Just in case something goes wrong with one. After all they are talking about exploring the oceanic portions of the moon? Just look at what we find deep beneath our very own oceans. Not much to see on the linear surface I believe just a waste. If they gonna invest so much time and money preparing for this mission the outcome better be worth it. I wanna see something I thought I would never see in my lifetime. Extraterrestrial Life.
David Xanatos
Just go. There's enough heat generated by teh tidal friction to melt an ocean nearly as big as our moon. That means there will be some very hot spots under that cold exterior. Look at the thermophiles that live - thrive - around volcanic vents in our salt water sea floor. They exist without so much as a single cold photon making its way to one of them. If there are the basic chemicals, sufficient available raw energy, and water - it won't just be some few items we'd only be able to see under a microscope - there'll be complex life forms developed there. They can have all of my tax dollars to go there with a well-thought-out probe. There will be a shift in global psychology if we find significant, well-developed complex life form out there, and it's a shift this planet needs.