Tag Archives: biosphere

Taking the air on the moons of Saturn

Sounds like something out of an Edwin Morgan* poem… but what are poems but dreams of possible truths, eh? From io9, suggestions based on Cassini probe data that Rhea, one Saturn’s many moons, might have a breathable oxygen-rich atmosphere:

It seems oxygen is far more abundant than we ever suspected, particularly on moons that seem to be completely frozen solid. We recently found evidence of oxygen on Jupiter’s moons Europa and Ganymede, and now this finding on Europa. In fact, because the region of space surrounding Saturn’s rings has an oxygen atmosphere, it’s thought even more of the icy moons within the gas giant’s magnetosphere likely have little atmospheres of their own.

According to new data from the Cassini probe, the moon’s thin atmosphere is kept up by the constant chemical decomposition of ice water on the surface of Rhea. It’s likely that Saturn’s fierce magnetosphere is continually irradiating this ice water, which is what helps to maintain the atmosphere. Researchers suspect a lot of Rhea’s oxygen isn’t actually free right now, but is instead trapped inside Rhea’s frozen oceans.

The last couple of years have seen the Rare Earth hypothesis take a number of serious body-blows, what with moons with atmospheres and oceans, and the sudden rash of exoplanet discoveries; I doubt I’m the only person here who isn’t too sad about that. 🙂

[ * Probably my favourite poet, and a trailbreaker in sf and concrete poetry right back in the Sputnik era, Edwin Morgan is already much missed. Rest in peace, sir. ]

Should Mars be treated like a wildlife preserve?

MarsFinding life on Mars would be pretty awesome, right? Of course it would – but it would also mean we’d have to change the way we work on the red planet, because of the ethical can of worms presented by contaminating a whole new biosphere.

We’ve already contaminated it, though – all of our probes and landers are likely festooned with Earthside microbes. Now some planetary scientists recommend that, should life be found, we remove or destroy our Martian hardware and keep things pristine:

He warns that Earth life could be reawakened if weather conditions on the planet change. This could happen as a result of periodic swings in the planet’s tilt, or if humans purposely alter the Martian environment, which, ironically, they might do to make conditions cosier for any Martian life they might discover. Microbes on subsurface drills in search of liquid water could also contaminate potential Martian habitats.

Here’s Jamias Cascio’s response:

… if life is found, definitely. No question. If fossilized life is found, also definitely, since that could mean dormant life, waiting for a Mars Spring.

If there’s no evidence of past or present life found… the question becomes more difficult. I always kind of sympathized with the Reds over the Greens in Kim Stanley Robinson’s Mars trilogy, but I also believe that establishing a human foothold off of Earth is a wise long-term survival strategy.

Could we justify changing the Martian climate, knowing that — as with Earth — such changes are irreversible?

The answer to that will depend on circumstance, I guess; it’s worth considering that the sort of political climate that would lead to greater exploration of Mars might well be the sort of climate that produces colonial attitudes. And the colonial era was pretty big on resource exploitation… [image by chipdatajeffb]

What do you think – should Mars be preserved pristine?

Self-sufficient space station proposed

Artist's impression of a lunar habitat module Yet another classic science fiction trope that real-world science is reaching towards: a team of scientists have come up with a design for a space station named "Luna Gaia" that works on similar principles to a biosphere – a "closed-loop" ecology where almost all waste products are recycled by the system. [Image credited to NASA]

The ISS runs on a type of closed-loop system already, but the recycling processes are largely based on chemical reactions; the biosphere design would use plants and algae instead, as far as is practically possible, and should be theoretically capable of sustaining twelve astronauts for three years. The diet sounds a bit dull, though …

[tags]space station, biosphere, astronauts[/tags]