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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

#121

Post by erik_seaberg »

thaumasiotes wrote: post #107
erik_seaberg wrote: post #101

Earlier quoted context omitted.

I'm reminded of > [Chlorine trifluoride is] also a stronger oxidizing agent than oxygen itself, which also puts it into rare territory. That means that it can potentially go on to “burn” things that you would normally consider already burnt to hell and gone, and a practical consequence of that is that it’ll start roaring reactions with things like bricks and asbestos tile. It’s been used in the semiconductor industry…

And from an MSDS for that... > Hazardous combustion products: None that are more toxic than the product itself. ( https://www.boconline.ie/en/images/chlorine_trifluoride_tcm6... ) It's a fun read.

Material Safety: None. The End.

> Contains no other components or impurities which will influence the classification of the product.

In the unlikely event you survive adding something, you won’t make it any better. You certainly can’t make it worse.

> Unsuitable extinguishing media: Water, Foam, Halons

> Specific methods: Move away from the container and cool with water from a protected position.

Um.

> May react violently with combustible materials.

Specifically, everything.

> Seek medical advice before using product.

“Don’t.”

> Ensure vehicle driver is aware of the potential hazards of the load

Driving is a strong indication that he is not aware.

> and knows what to do in the event of an accident or an emergency.

“Run.”

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

#122

Post by eru »

walrus01 wrote: post #118
eru wrote: post #115

Earlier quoted context omitted.

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 drill…

What odds would make you take the bet?

And, perhaps let's talk about a conditional bet that removes the difficulty of space exploration:

The bet pays me X dollars, if human vessels can go to the asteroid belt and not find life. It pays you Y dollars, if we find life. And no payment in either direction, if we can't go to the asteroid belt and don't find life. Say, all limited to the next 100 years.

What's the ratio of X to Y that would make you accept such a bet?

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

#123

Post by henearkr »

at_a_remove wrote: post #110
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…

Oh, I remember the convection cell Qax from Baxter, read Dragon's Egg when it came out, or Brin's Sundiver for solar dwellers, or go even further back for the Piers Anthony's OX , even the frozen lattices of light from 2001 . I could try speculating on some pretty strange forms of life, and have, but ultimately life -- and as fuzzy as that term is -- might well be construed as interlocking sets of cycles, self-perpet…

Nice to see that I speak with a peer SF lover! ^^

I agree, I would be surprised if we discover first alien life in a non-chemical form. Somehow though I would love to be surprised!

There are so many possible environments and substrates, and we cannot think of all of them. The multiplicity of the places where things could happen, and the scale and age of the universe, also increase the possibilities that there are places with the right conditions or stability. The conditions on Earth were kind of lab-grade perfect too! Any nearby supernova, ill-directed solar flare, etc. could have nipped life in the bud. Only the huge number of Earth-like environment in the universe, and the large interval of time allotted, can justify that we have had the chance to arise in these conditions.

PS: also, to be fair, a lot of life forms in Baxter are actually engineered. But our First Contact (or First Observation) could be as well with a "natural" form as with an artifact! And that would not matter that much.

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

#124

Post by martinpw »

interfixus wrote: post #95

> Ceres is the largest object in the asteroid belt between Mars and Jupiter and has its own gravity, enabling the Nasa Dawn spacecraft to capture high-resolution images of its surface Scratching my head. Trying as I may. But not making sense. [insert subthread about Gell-Mann amnesia here]

Yes, clearly every asteroid has its own gravity. I guess what it should say is that it has a strong enough gravitational field to allow a spacecraft to be placed into orbit and have it stay there.

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

#125

Post by EdwardDiego »

ckuehl wrote: post #68
outworlder wrote: post #17

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

The authors of The Expanse published an article last year acknowledging and paying tribute to the mission ("How a NASA robot messed up our science fiction"): https://www.nationalgeographic.com/science/2019/02/dear-dawn...

Love them even more for that.

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

#126

Post by valuearb »

walrus01 wrote: post #118
eru wrote: post #115

Earlier quoted context omitted.

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 drill…

The Space Shuttle payloads to LEO cost $40,000 per pound.

Before SpaceX commercial launch payloads cost $5,000 to $10,000 per pound.

Falcon 9 payloads cost around $1,500 per pound.

Falcon Heavy payloads cost around $1,100 per pound.

Starship payloads will cost between $100 and $500 per pound. It will be able to lift at least 100 tons to orbit. And using in orbit refueling, it will be able to accelerate that 100 ton payload 6.9 km/sec, making landing it on Ceres trivial.

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

#127

Post by dflock »

walrus01 wrote: post #47
klyrs wrote: post #29

Earlier quoted context omitted.

The title says "water" but the article says "brine". Don't count on it.

Assuming for a moment the technology/scifi world of The Expanse, one thing that doesn't seem to be a scarce resource is electrical power, due to plentiful nuclear reactors. Wouldn't it be possible to flash brine into steam and separate the h2o from the salt, storing the salt in solid cubes or something?

Brine is pretty corrosive, more so if you heat it up, but you you could do that, yes.

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

#128

Post by valuearb »

ncmncm wrote: post #87
randomdude402 wrote: post #79

Earlier quoted context omitted.

I thought the atmosphere was mostly carbon dioxide and sulfuric acid. What makes it potentially high value?

Earth-normal gravity, Earth-normal temperature, Earth-normal pressure, concentrated solar power, breathing air is buoyant, plastic and carbon fiber structural material--and breathing air and water--are convertable from atmosphere, cloud water is heavily enriched with deuterium. Way nicer than Mars. You can operate an unshielded nuke plant tethered some distance below your balloon habitat, no worries about leaks. We d…

it is extremely unlikely that humans can’t live on a Mars, in suitable habitats. One third gee is far closer to one gee in effect than it is zero gee.

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

#129

Post by 082349872349872 »

ncmncm wrote: post #84
PaulHoule wrote: post #65

Earlier quoted context omitted.

If your definition of habitable is "has liquid water" probably most of the habitable places in the universe are like Ceres, the moons of Saturn, even deep inside Pluto. Between the effects of pressure, geothermal energy, and gravitational tides you find liquid water in those places more than the inner solar system where water gets evaporated and blown away. (The trouble is that those places don't have sunlight and pr…

Rocky planets are interesting only to extreme primitives. Once you leave the nest, Oort cloud objects are the most useful. That is where to look for visitors.

"But Moooooom, I hate having a few seconds lag to all my friends."

"If all your friends descended to the bottom of a gravity well, you would too? After all, we're not savages."

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

#130

Post by ncmncm »

valuearb wrote: post #128
ncmncm wrote: post #87

Earlier quoted context omitted.

Earth-normal gravity, Earth-normal temperature, Earth-normal pressure, concentrated solar power, breathing air is buoyant, plastic and carbon fiber structural material--and breathing air and water--are convertable from atmosphere, cloud water is heavily enriched with deuterium. Way nicer than Mars. You can operate an unshielded nuke plant tethered some distance below your balloon habitat, no worries about leaks. We d…

it is extremely unlikely that humans can’t live on a Mars, in suitable habitats. One third gee is far closer to one gee in effect than it is zero gee.

There is no basis for any kind of quantitative estimate of likelihood.

Flatlander wishful thinking is soon fatal out in the asteroid belt. You quickly learn better, or die.

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