Searching For Ocean Life On Another World

An anonymous reader writes: National Geographic has a detailed article about efforts underway to search for life in the oceans of Europa, which are buried beneath miles of ice. A first mission would have a spacecraft orbit just 16 miles over the moon's surface, analyzing the material ejected from the moon, measuring salinity, and sniffing out its chemical makeup. A later mission would then deploy a rover. But unlike the rovers we've built so far, this one would be designed to go underwater and navigate using the bottom surface of the ice over the oceans. An early design was just tested successfully underneath the ice in Alaska. "[It] crawls along under a foot of ice, its built-in buoyancy keeping it firmly pressed against the frozen subsurface, sensors measuring the temperature, salinity, pH, and other characteristics of the water."

Astronomers and astrobiologists are hopeful that these missions will provide definitive evidence of life on other worlds. "Europa certainly seems to have the basic ingredients for life. Liquid water is abundant, and the ocean floor may also have hydrothermal vents, similar to Earth's, that could provide nutrients for any life that might exist there. Up at the surface, comets periodically crash into Europa, depositing organic chemicals that might also serve as the building blocks of life. Particles from Jupiter's radiation belts split apart the hydrogen and oxygen that makes up the ice, forming a whole suite of molecules that living organisms could use to metabolize chemical nutrients from the vents."

Obligatory

[stewsters]

Attempt no landing there.

But seriously, cool stuff.

How do they plan to send communications back to earth from under the ice? I assume they will have a rover on the surface that will communicate with the diver and possibly a satellite, that will communicate with us.

Re:Obligatory

[Anonymous Coward]

I was wondering the same thing (about communications). Depending on how many miles of ice we're talking about would determine if any form of tethered array could be used (i.e. - "diver" drills / melts into ice for 1 or 2 miles, leaving along a cord which is connected to an uplink sat system which communicates to whatever it floating in orbit, etc.) Not sure what kind of materials we have that could ensure that the cord wouldn't break but I would think that even 2 miles worth of cord would be an awful lot to lug around for something that would have to be very energy efficient...

Otherwise, maybe as the system goes deeper and deeper, it could leave behind repeaters every N distance and communicate back to the uplink system via an array of these repeaters...?

Very interesting stuff (I wish I knew more about it!).

Re:Contamination

[mbone]

I wonder what they are doing to guard against contamination from Earth bugs. IIRC, the Mars rovers showed up as dirty.

Lots. Europa is in the elite Category III / IV of planetary protection [nasa.gov], along with Mars and Enceladus,

“where there is a significant chance that contamination carried by a spacecraft could jeopardize future exploration.” We define “significant chance” as “the presence of niches (places where terrestrial microorganisms could proliferate) and the likelihood of transfer to those places."

The Europa probe is likely to get a little less scrubbing, significantly less than an Europan orbiter, but more than the Juno spacecraft [nasa.gov], as, although it will be in a Jovian orbit going near Europa, it can be placed in a "safe" orbit away from Europa at the end of the mission. But, Europa orbiters and landers will get the full treatment.

By the way, even if Mars landers had some bugs, they were sterilized, which undoubtedly greatly reduced the total bio-loading, Just because you didn't wash your hands once before dinner doesn't mean you should stop washing them altogether subsequently.