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Planet Ceres is an 'ocean world' with sea water beneath surface, mission finds

theguardian.com

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Re: Planet Ceres is an 'ocean world' with sea water beneath surface, mission finds

#111

Post by austincheney »

gaukes wrote: post #2

Ceres is one of the more interesting candidates for life in our solar system. Ceres is in the habitable zone for our solar system (although just barely), it's surface temperature is -30 F (eq. to winter in Greenland), and it's detected that the water on the surface is 20% carbon by mass (though that can mean a lot of things).

-30F is too cold for Earth life though. Enceladus is known to have substantial warm salt water.

https://en.m.wikipedia.org/wiki/Extraterrestrial_liquid_wate...

Re: Planet Ceres is an 'ocean world' with sea water beneath surface, mission finds

#112

Post by henearkr »

Balgair wrote: post #102
henearkr wrote: post #89

Earlier quoted context omitted.

You only considered chemistry-based life. Cannot hold it against you of course. But some hard SF writers like Baxter also imagined life based on electromagnetic interactions, nuclear reactions (life in the mantle of a neutron star), fluid vortices and turbulences (life in liquid or gaseous planets), etc. Basically he included a lot of substrates that could be used to implement complexity. Also, a big drawback of sear…

That neutron star story is wild . Hard recommendation to read. One point I have with Baxter is that his premises are just bananas, but the people acting in them are pretty recognizable. To be fair, if the characters were also nutter-butter, no one would read it, as it wouldn't be a story anymore, just a strangely formatted research paper. https://en.wikipedia.org/wiki/Flux_(novel)

I don't know if you read the other books from the Xeelee series, but the neutron star is probably not even the strangest life form Baxter considered :) I don't want to spoil too much though.

Re: Planet Ceres is an 'ocean world' with sea water beneath surface, mission finds

#113

Post by edgyquant »

renewiltord wrote: post #73
stx wrote: post #36

Is this actually H2O water? I read the article but I am still unclear. I am often excited to hear that water was discovered on some planet or moon but its always a disappointment to learn that its liquid methane or some other liquid that is not actually H2O water.

What other kind of substance is called 'water'? As far as I know only H2O is described as water.

Water usually means liquid H2O. Europa, for instance, isn't liquid water but ice that is squeezed and loosened to the point it acts like a liquid while still being well below freezing and basically just ice sand

Re: Planet Ceres is an 'ocean world' with sea water beneath surface, mission finds

#114

Post by QuadrupleA »

gaukes wrote: post #2

Ceres is one of the more interesting candidates for life in our solar system. Ceres is in the habitable zone for our solar system (although just barely), it's surface temperature is -30 F (eq. to winter in Greenland), and it's detected that the water on the surface is 20% carbon by mass (though that can mean a lot of things).

Hmm... according to wikipedia Ceres' surface is 110 - 155 Kelvin, or a toasty -262 to -181°F.

https://en.m.wikipedia.org/wiki/Ceres_(dwarf_planet)

Which makes sense, with little to no atmosphere.

If that's correct I'm a little surprised this got voted up to top comment.

Re: Planet Ceres is an 'ocean world' with sea water beneath surface, mission finds

#115

Post by eru »

walrus01 wrote: post #97
gaukes wrote: post #2

Ceres is one of the more interesting candidates for life in our solar system. Ceres is in the habitable zone for our solar system (although just barely), it's surface temperature is -30 F (eq. to winter in Greenland), and it's detected that the water on the surface is 20% carbon by mass (though that can mean a lot of things).

Considering that there's organisms that live at ridiculous pressures, with absolutely no sunlight and at the extreme temperatures of deep sea volcanic vents, I would not be surprised at all. https://en.wikipedia.org/wiki/Hydrothermal_vent https://en.wikipedia.org/wiki/Hydrothermal_vent_microbial_co...

I would still be surprised in the sense that I would gladly give you 100 to 1 odds that we won't find non-earth life on Ceres in the next hundred years.

What are your odds?

Re: Planet Ceres is an 'ocean world' with sea water beneath surface, mission finds

#116

Post by unchocked »

autokad wrote: post #53
jojobas wrote: post #28

Earlier quoted context omitted.

All the water on Earth was drunk at some stage wasn't it?

drunk by a human or drunk at all? I'd suspect that not all water has been drunk at all, but lets cover the human part. Lets say the average human drinks 3 liters per day and lives 80 years (3 * 365 * 80 ) = 87,600 liters per human. there have been about 100 billion humans so 100 b * 87600 =8,760,000,000,000,000 liters have been drunk. there are about this many liters in Earths 5 oceans (source google search): 1,400,0…

The point is that in being drank, water is not destroyed.

Re: Planet Ceres is an 'ocean world' with sea water beneath surface, mission finds

#117

Post by eru »

crowbahr wrote: post #108
walrus01 wrote: post #97

Earlier quoted context omitted.

Considering that there's organisms that live at ridiculous pressures, with absolutely no sunlight and at the extreme temperatures of deep sea volcanic vents, I would not be surprised at all. https://en.wikipedia.org/wiki/Hydrothermal_vent https://en.wikipedia.org/wiki/Hydrothermal_vent_microbial_co...

The question is can life arise in such an environment, or only migrate to one. That's yet to be determined as far as I know: extremophiles have all evolved from less tolerant life forms as far as I'm aware.

Though, of course, you might expect to see that, even if life can arise in extreme environments:

It's uncontroversial that life is much denser in more hospitable environments. If the extreme environments are in regular contact with the hospitable environments, and if evolution is sufficiently random, you would expect over time that most organisms anywhere have an ancestor in the hospitable environment.

Even if life can arise in the extreme environment.

Re: Planet Ceres is an 'ocean world' with sea water beneath surface, mission finds

#118

Post by walrus01 »

eru wrote: post #115
walrus01 wrote: post #97

Earlier quoted context omitted.

Considering that there's organisms that live at ridiculous pressures, with absolutely no sunlight and at the extreme temperatures of deep sea volcanic vents, I would not be surprised at all. https://en.wikipedia.org/wiki/Hydrothermal_vent https://en.wikipedia.org/wiki/Hydrothermal_vent_microbial_co...

I would still be surprised in the sense that I would gladly give you 100 to 1 odds that we won't find non-earth life on Ceres in the next hundred years. What are your odds?

Without a significant drop in the $ per kg cost of putting stuff in low earth orbit, I wouldn't take that bet. I don't think SpaceX starship will be revolutionary enough to put probes in LEO cheap enough.

Once in orbit it's possible to reach things in the asteroid belt entirely through very high efficiency ion/hall effect thruster propulsion, which can have specific impulse as high as 8000.

Any probe capable of drilling or melting into the crust of ceres or Europa or similar will have to be quite large...

Re: Planet Ceres is an 'ocean world' with sea water beneath surface, mission finds

#119

Post by eru »

loosetypes wrote: post #91
gaukes wrote: post #2

Ceres is one of the more interesting candidates for life in our solar system. Ceres is in the habitable zone for our solar system (although just barely), it's surface temperature is -30 F (eq. to winter in Greenland), and it's detected that the water on the surface is 20% carbon by mass (though that can mean a lot of things).

Would evolutionary timelines or cycles be slower in an overall colder planet? (Thinking of those interactive diagrams for temperature on the kinetic energy of molecules zooming around in closed space)

Well, at least that seems to be the case on earth. Creatures from the cold deep sea have slower life cycles than creatures in the tropics.

Re: Planet Ceres is an 'ocean world' with sea water beneath surface, mission finds

#120

Post by loosetypes »

clarkmoody wrote: post #109
loosetypes wrote: post #91

Earlier quoted context omitted.

Would evolutionary timelines or cycles be slower in an overall colder planet? (Thinking of those interactive diagrams for temperature on the kinetic energy of molecules zooming around in closed space)

Did you ever read Dragon's Egg ? It's a speculative hard sci-fi that posits ultra-fast evolution for life on the surface crust of a neutron star !

Interesting! Thanks. No I have not.

Although I was previously recommended Rocheworld by a former NASA researcher, with the note that Robert L. Forward made every effort to describe a scientifically plausible double planet.

Incidentally, it looks like Dragon’s Egg is his only work available on Audible. I’ll add it to my list.

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