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

theguardian.com

151–160 of 264 posts

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

#151
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.

in case you’re wondering: That’s between -163,15 and -118,15 °C.

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

#152

Earlier quoted context omitted.

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 drill…

Wouldn’t a nuke work?

Please elaborate.

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

#154

There goes the water rationing narrative in The Expanse...

I thought Co[r]vid-19 had already blew most of The Expanse out of the water.

Pretty sure ravens aren't related to this discussion ;-)

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

#155

Earlier quoted context omitted.

> Another problem with silicon is that its basic oxide (Silicon Dioxide) is a solid that is non-reactive with virtually everything. I was amused once by reading an MSDS for silicon dioxide. As I presume is required, they do list some hazards of exposure, but if you read the sheets for other substances the contrast is pretty striking. Look at the health effects listed on https://fscimage.fishersci.com/msds/09890.htm :…

SiO2's "toxicity" is more mechanical than chemical (it's coarse and rough, etc) But it's pretty much inert chemically (for human levels of chemical reactions)

Sure. It's just sand, and it gets everywhere.

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

#156
post #154

Earlier quoted context omitted.

I thought Co[r]vid-19 had already blew most of The Expanse out of the water.

Pretty sure ravens aren't related to this discussion ;-)

Got my eclipse phase wires crossed https://eclipse-phase.fandom.com/wiki/Blackbird_1e

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

#157
Very interesting observations!

I think many planets may have life below the surface. The hot core of planets behave like a heat reactor. Somewhere between the hot planet core and cold planet surface there should be a balanced temperature a mix. That mix may have a temperature of 0-37C.

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

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

#158
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).

> the water on the surface is 20% carbon by mass

Sorry, can you explain what you mean by this? Are you using "water" figuratively for all liquid, as opposed to H2O?

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

#159

Earlier quoted context omitted.

Numerous other ideas exist for alien life, but most of them have their shortcomings. It all boils down to chemical reactions and physics. Imagine a universe of only helium. No valence electrons would be readily available, so chances are you are not going to see helium molecules. Lithium, sure, as a metal. Continue examining various smaller (and more plentiful elements). Fluorine? Well, only one slot available, so you…

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…

Reminds me Solaris written by Lem. https://en.m.wikipedia.org/wiki/Solaris_(novel)

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

#160

Earlier quoted context omitted.

Numerous other ideas exist for alien life, but most of them have their shortcomings. It all boils down to chemical reactions and physics. Imagine a universe of only helium. No valence electrons would be readily available, so chances are you are not going to see helium molecules. Lithium, sure, as a metal. Continue examining various smaller (and more plentiful elements). Fluorine? Well, only one slot available, so you…

Thank you for that write up. What about non-chemical life. What I mean by that is something like a giant CPU with traces literally the size of freight trains? I recently finished the first Dark Tower book and it’s got me thinking about scale.

Then you run into speed of light issues. In one nanosecond, that is one 1GHz cycle, light travels only ~30cm.
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