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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

#131

Post by Dragonai »

at_a_remove wrote: post #48
toshk wrote: post #16

Earlier quoted context omitted.

I always wondered why we are overly focused on the conditions that created life on earth. Arguably it makes sense to see similar conditions lead to life. But do we really know enough to assume that's only way?

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…

Terrific comment. Thank you so much for the excellent explanation!

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

#133

Post by azernik »

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.

This is possible, but we don't actually know for sure. Only in the last few years has there been hardware on the ISS capable of creating partial-g for rodents [1], and so far (in published research, at least) it hasn't been used for anything except 1g.

[1] https://www.nature.com/articles/s41598-017-10998-4

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

#134

Post by thaumasiotes »

erik_seaberg wrote: post #121
thaumasiotes wrote: post #107

Earlier quoted context omitted.

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 viol…

To be fair, most stuff involving fluorine is like this. Compare https://fscimage.fishersci.com/msds/11171.htm (for extra chlorine trifluoride fun, this is one of the things you get if you react it with... water. Hence the entry in "unsuitable extinguishing media".):

> Danger! May be fatal if inhaled, absorbed through the skin or swallowed. Both liquid and vapor can cause severe burns to all parts of the body. Specialized medical treatment is required for any exposure... can cause metabolic imbalances with irregular heartbeat, nausea, dizziness, vomiting and seizures. Long-term exposure may cause bone and joint changes. Will attack glass and any silicon-containing material. Corrosive to metal.

> Potential Health Effects

> Eye: Contact with liquid or vapor causes severe burns and possible irreversible eye damage.

> Skin: May be fatal if absorbed through the skin. Causes severe burns with delayed tissue destruction. Substance is rapidly absorbed through the skin. Penetration may continue for several days. Causes severe tissue necrosis and bone destruction.

> Ingestion: Causes severe digestive tract burns with abdominal pain, vomiting, and possible death.

> First Aid Measures

> Eyes: Do NOT allow victim to rub eyes or keep eyes closed. SPEEDY ACTION IS CRITICAL! GET MEDICAL ATTENTION IMMEDIATELY!

> Skin: Discard contaminated clothing in a manner which limits further exposure. Destroy contaminated shoes. Spills should be flushed until medical attention arrives. SPEEDY ACTION IS CRITICAL! GET MEDICAL ATTENTION IMMEDIATELY.

> Ingestion: Get medical aid immediately. SPEED IS ESSENTIAL. A DOCTOR MUST BE NOTIFIED AT ONCE.

> Inhalation: SPEED IS ESSENTIAL, OBTAIN MEDICAL AID IMMEDIATELY. POISON material. If inhaled, get medical aid immediately.

(ALL CAPS are original to the MSDS.)

> Wear chemical splash goggles and face shield.

> Wear butyl rubber gloves, apron, and/or clothing.

> Wear appropriate protective clothing to prevent skin exposure.

> Wear a NIOSH/MSHA or European Standard EN 149 approved full-facepiece airline respirator in the positive pressure mode with emergency escape provisions.

> Never work alone with this chemical.

> Substance is noncombustible

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

#135

Post by fsloth »

Razengan wrote: post #106
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…

"Life" could also be AI machines. If we seeded a planet with sufficiently advanced robots, that can mine and build and learn and make copies of themselves on their own, and a few centuries later they have a civilization, does it matter what they're made of? For all intents and purposes, it would be life. Perhaps at some point we should/will have to stop saying "life" at some point and use terms like "agent" instead,…

I don't think you should confuse life and agency. I fail to see how a bacteria would have any agency.

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

#136

Post by JohnBooty »

toshk wrote: post #16
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).

I always wondered why we are overly focused on the conditions that created life on earth. Arguably it makes sense to see similar conditions lead to life. But do we really know enough to assume that's only way?

    But do we really know enough to assume that's only way?
I've never heard anybody in the sciences make that assumption. It's just that other biochemistries are speculative at best. Searching for this stuff is time- and resource-intensive, so naturally we look for the sort of life in which we have some expertise.

And to be fair, we are not exclusively looking for Earth-like biological markers. Lots of people looking out for signs of Dyson spheres or other biology-agnostic possible signs of life.

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

#137

Post by bjo590 »

Animats wrote: post #66

Ceres is a good place for a lander and rover then. Might be some action there. Face it, Luna and Mars are boring, low-value real estate.

> Face it, Luna and Mars are boring, low-value real estate.

It's worth noting that Ceres, and by proxy the vast material wealth of the Asteroid Belt, is only 25% further from Earth than Mars is. The biggest barrier is Ceres has 10% of the gravity of Mars or about 3% of the gravity of Earth. This isn't even close to enough for anything we would consider healthy living.

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

#138

Post by Razengan »

fsloth wrote: post #135
Razengan wrote: post #106

Earlier quoted context omitted.

"Life" could also be AI machines. If we seeded a planet with sufficiently advanced robots, that can mine and build and learn and make copies of themselves on their own, and a few centuries later they have a civilization, does it matter what they're made of? For all intents and purposes, it would be life. Perhaps at some point we should/will have to stop saying "life" at some point and use terms like "agent" instead,…

I don't think you should confuse life and agency. I fail to see how a bacteria would have any agency.

> I fail to see how a bacteria would have any agency.

Why would it not?

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

#139

Post by Joeri »

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…

In any particular glass of water, supposedly almost all of it was drunk by a dinosaur.

https://youtu.be/KK64DqpIy0s

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

#140

Post by JohnBooty »

marcusverus wrote: post #92
shakna wrote: post #12

Earlier quoted context omitted.

Earth might have a subsurface ocean as well [1], though I haven't found any follow up since 2014 on that one. [1] http://dx.doi.org/10.1126/science.1253358

>They conclude that the mantle transition zone--410 to 660 km below the Earth's surface--acts as a large reservoir of water. Sadly there will be no eyeless space whales in our basement, given that the temperature at that depth on Earth is around 2,000° Celsius.

eyeless FIRE whales
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