Four of Uranus’ largest moons likely contain an ocean layer
nasa.gov
nasa.gov
One thing that I think is important to consider is that what is really needed is an energy gradient which can be leveraged to do the work of creating all the different kinds of compounds one would need to produce something we'd call "alive".
I think the other article from quanta about "assembly theory"[1] is a good one to consider in this context. What would be the "Assembly Contingent" of a world like Europa or these other moons?
My guess would be that there might be enough material and energy potential to allow pathways to bacteria analogues (not that these def exist, but they're possible), but not nearly enough to support the variation and specialization required to reach multi-cellular life.
[1] https://www.quantamagazine.org/a-new-theory-for-the-assembly...
https://spacethoughtsblog.wordpress.com/2015/10/01/addressin....
It’s just so damn cold out there, how could life start/survive.
Not that I’m any expert but at a guess.
And earth still hosts plenty of geothermal life - bacterial, archaean, all the way up to tube worms.
This is qualified. There are abiogenesis models that occur entirely in e.g. tide pools.
Idk. How did it start here?
> It’s just so damn cold out there
Life can find energy to run near hydrothermal vents[1], or naturally occurring nuclear reactors [2], or perhaps exploiting tidal heating[3].
I would also be not surprised if there are ways to run life on much lower energy gradients than what we are accustomed to here on Earth. Some weird biochemical tricks, perhaps a much slower life cycle. I don't know how that would look like, I'm just saying simply "Life..ehm..will find a way".
1: https://www.nhm.ac.uk/discover/survival-at-hydrothermal-vent... 2: https://en.wikipedia.org/wiki/Natural_nuclear_fission_reacto... 3: https://en.wikipedia.org/wiki/Tidal_heating#Moons_of_Gas_Gia...
There's probably twice as much water in Europa's ocean than there is on all of Earth.
https://solarsystem.nasa.gov/moons/jupiter-moons/europa/in-d...
I think we'll find Cthulhu down there, if we ever get around to drilling through a few km of ice to look (or learn to scan from the surface somehow).
I can't decide what's weirder: That it'd use similar DNA/RNA for replication, or that it wouldn't.
See the chart here: https://physics.stackexchange.com/q/615311
Earth is average 287 Kelvin. Mars can just about keep hold of all CO2 at that temperature. A smaller body would need to be colder to hold on to the same materials, or some other method of reducing escape.
Unlikely. The moons of Uranus appear to not have atmospheres.
There is this cool paper[1] about how they measured the lack of atmosphere for one of the moons (Titania). They measured carefully the light of a star as the moon occluded it. If there were atmosphere there they would have seen it.
No atmosphere, no runaway greenhouse gas process. At least not how we know it.
The point I'm responding to is "It's too cold out there". Maybe an earth-size planet with an atmosphere like Venus would still be warm?
I cannot get into the article, but maybe gravitational stress on the moons from Uranus is enough to provide heat.
"On Earth, the ocean floor is home to hydrothermal vents that spout hot water, nourishing life in an otherwise inhospitable environment. Scientists think similar vents could exist on other worlds such as Jupiter's moon Europa and Saturn's moon Enceladus."
https://solarsystem.nasa.gov/resources/17647/earth-undersea-...
It's quite the elegant system.
Also, there are microbes found in volcanic vents and in Antarctica. I don't think temperature is big a limiting factor as you seem to think.
As someone once said: Life finds a way.
It won't always be this way. The sun is destined to become a red giant, which may put the Solar System's distant watery and icy moons in a comfy habitable zone.