Our solar system has no shortage of liquid water.
In addition to it hallmarking earth, it’s also thought to potentially exist in multiple
other bodies in the solar system locked under ice shells.
The most famous examples of this are Europa and Enceladus.
Both have periodically been in the news lately because unlike some places, such as proxima
B, the chances for life potentially being present in the oceans of these moons are solidly
on the rise.
In general, we hear most about Europa.
At first sight, it seems to edge out Enceladus as a possible abode of life.
The main reason for this is that It appears to be significantly older than Enceladus,
as old as the solar system itself, whereas Enceladus could be a relatively recently formed
body, as little as a hundred million years ago, though this is not yet settled.
If young, however, is that enough time for life to have arisen?
The first step in answering this question was to determine if Enceladus’ waters are
habitable at all.
Recent studies of plumes of water spraying into space from cracks in Enceladus’ ice,
see my video on that topic in the end screen of this video, suggest that it is, with evidence
of active geology in the form of volcanic ocean vents, possibly very much like those
of earth, which are hotbeds for life on this world.
That evidence came in the form of silicates present in the plumes.
Also present were organics, and lots and lots of water.
But intriguingly, there were two other chemicals.
Molecular hydrogen, which hydrothermal vent action is a solid candidate for the source
of, and methane.
Methane also can be produced by hydrothermal vents, but it’s also noteworthy for being
one of the chemical signatures of life.
But could microbes live under the conditions present in Enceladus oceans?
As it turns out, at least one earth microbe could.
In a paper by Ruth-Sophie Taubner and colleagues, link in the description below, they detail
that earth microbes known as methanogenic archaea might be suited for an Enceladus hydrothermal
vent environment.
This group of microbes play a prominent role here on earth and they could be among the
oldest classes of lifeform.
They typically do not deal well with oxygen, so instead of O2, they use molecular hydrogen,
H2, and carbon dioxide to produce methane.
The researchers determined that the actual geologic process that creates the H2 on enceladus,
serpentization of olivine, could produce enough hydrogen for this kind of life.
They continue on to say that they identified a specific methanogen, Methanothermococcus
okinawensis, that could live on Enceladus, as we understand the conditions of its ocean.
More, if a similar, but alien, microbe is living on Enceladus, it could hypothetically
be producing some of the methane observed in the plumes.
But, of course, since methane can be produced geologically, this is not definitive.
Sample return mission needed.
But ultimately it still goes back to the question of whether life has had enough time at Enceladus
to arise at all.
No one knows, for two reasons.
First the actual age of Enceladus hasn’t yet been well constrained.
If it is indeed a young body, life would have had to arise very rapidly, as soon as the
conditions were right.
Reason number two is that we don’t yet have a complete picture of just what the genesis
of life looks like or what those exact conditions might be for it to occur.
But we do know that organic chemical reactions can happen very rapidly.
Perhaps so much so that as soon as the conditions are right, microbial life arises anywhere
it can as fast as it can and the universe could be teeming with simple life.
How that life develops from simple to complex, or even intelligent, is a matter of circumstance,
but from our own planet we know that great things can happen under the right conditions.
Thanks for listening!
I am futurist and science fiction author John Michael Godier currently eyeing a tomato suspiciously
and coining the term retribution salad.
It was all fun and games for the anaerobes until the plants showed up and oxygenated
everything.
And if that wasn’t bad enough, then they went on to enslave higher organisms that evolved
through oxygen dependency.
For the love of corn, look at the herbivores!
How sad is that?
Time for lunch and be sure to check out my books at your favorite online retailer and
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unknown aspects of this amazing universe in which we live.