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NASA’s Webb finds carbon source on surface of Jupiter’s moon Europa

webbtelescope.org

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Re: NASA’s Webb finds carbon source on surface of Jupiter’s moon Europa

#241

Post by whimsicalism »

omnicognate wrote: post #232
whimsicalism wrote: post #180

Earlier quoted context omitted.

> The distances involved, the speed of light and inverse square laws mean we wouldn't expect to have detected aliens yet if they are there That’s not true at all - simple assumptions would make it likely we would have encountered intelligent life if it evolved in the past in this galaxy.

We don't have the technology to detect signals similar to our own from the distance of even the nearest stars [1], and there is no reason to assume that more technologically advanced civilisations will generate vastly larger signals. Therefore the absence of detection to date tells us nothing, except to place an extremely generous upper bound on the power of signals they generate. [1] https://www.seti.org/press-relea…

We wouldn’t need to detect signals - life arising only a few hundred million years earlier than us would easily have been able to send physical artifacts/vehicles/harvesting to every system in the entire galaxy if they had interstellar travel.

If life were common enough that it has evolved multiple times in the same solar system (excluding panspermia) then this becomes almost a certainty that it should have occurred

Re: NASA’s Webb finds carbon source on surface of Jupiter’s moon Europa

#242

Post by bmitc »

hutzlibu wrote: post #200
bmitc wrote: post #189

Earlier quoted context omitted.

There will always be people that don't know what you know and vice versa. It's a given fact of life. It's like forgetting that the sky is blue. Haha. I.e., I agree with you, but your statement is more humble than the last.

"but your statement is more humble than the last." It also was a different person ..

I know it was a different person.

Re: NASA’s Webb finds carbon source on surface of Jupiter’s moon Europa

#243

Post by jayGlow »

jcims wrote: post #211
spartanatreyu wrote: post #102

Earlier quoted context omitted.

Sticking with just the Jovian moons, both Ganymede and Callisto are thought to have subsurface oceans too. Ganymede's oceans might be the largest in the entire Solar System. 1. https://en.wikipedia.org/wiki/Ganymede_(moon)#Subsurface_oce... 2. https://en.wikipedia.org/wiki/Callisto_(moon)#Internal_struc...

800km deep. Oof. Seems like an ocean world could develop intelligence but technology would be quite difficult.

there are some pretty cool scifi books that look at how an aquatic species might develop technology. the "ringworld's children" involves a species that develops on a frozen world with an ocean beneath the ice.

Re: NASA’s Webb finds carbon source on surface of Jupiter’s moon Europa

#244

Post by simongray »

bbor wrote: post #208
simongray wrote: post #197

> NASA's Webb I guess it may be technically owned and primarily operated by NASA, but it was developed from the start as an international project: https://en.wikipedia.org/wiki/James_Webb_Space_Telescope#Par...

I also hate American-centrism but it seems kinda justified here - they do go out of their way to mention ESA and CSA at the end, as well. From that article: NASA's lifetime cost for the project is[when?] expected to be US$9.7 billion, of which US$8.8 billion was spent on spacecraft design and development and US$861 million is planned to support five years of mission operations.[112] Representatives from ESA and CSA s…

Fair enough.

Re: NASA’s Webb finds carbon source on surface of Jupiter’s moon Europa

#245

Post by joe__f »

uoaei wrote: post #235
bmitc wrote: post #193

Earlier quoted context omitted.

I don't know what that means. The statement just wasn't useful and comes across as sassy and arrogant.

Do you think it's belittling to point out that someone may not have scientific knowledge? Ie, is the statement something beyond mere fact? What makes having scientific knowledge good, that you may infer that someone may think not having it is bad?

My first reading of the sentence in question was that it was patronising

Re: NASA’s Webb finds carbon source on surface of Jupiter’s moon Europa

#246

Post by c54 »

JshWright wrote: post #224
c54 wrote: post #177

Earlier quoted context omitted.

Metabolism converts sugars and oxygen to carbon dioxide and water. Fire has the same inputs and outputs too! You can think of metabolism as releasing the same energy as fire but with more steps so our bodies can harness and use the energy via various other chemical reactions. Most of the water from metabolism is released in your breath. Water you pee is mostly water you ingested via drinking and eating.

The water you exhale is just the amount of water that happens to evaporate in your respiratory tract/lungs. The water you urinate is whatever "extra" water is left over (based on a bunch of factors like blood pressure, how much stuff is dissolved in you blood, etc). The water that leaves via your lungs and the water that leaves via your kidneys all had to get there via your blood. There's no distinction made based on…

Yes agreed fair enough

Re: NASA’s Webb finds carbon source on surface of Jupiter’s moon Europa

#247

Post by VerminOctopus1 »

keepamovin wrote: post #168
ramraj07 wrote: post #140

Earlier quoted context omitted.

Did they use a secret trillion dollar X ray glass telescope to peer through Europa's miles thick ice sheet and see?

Skepticism is warranted, but there's no need for mockery. It only insults your humility in front of the great mystery. But to answer the question: I think they drilled down there, or sent a probe, but equally it could have been something told to them by an ET. But I can't recall the specifics.

Mockery is deserved in this case. Not every cartoonish and outlandish claim needs to be engaged with seriously.

Re: NASA’s Webb finds carbon source on surface of Jupiter’s moon Europa

#248

Post by namirez »

buffington wrote: post #236
globular-toast wrote: post #190

Earlier quoted context omitted.

[flagged]

Perhaps I misunderstood your original comment. I interpreted what you said as meaning that the hydrogen and oxygen atoms that make up an H2O molecule had to be derived from H2O molecules. After all, your words were: > oxygen comes from plants and plants get it from water and the hydrogen comes from hydrocarbon fuels where the hydrogen comes from water again Then: > technically you can never create new water on Earth…

Please pay more attention to the user names.

Re: NASA’s Webb finds carbon source on surface of Jupiter’s moon Europa

#249

Post by andrewflnr »

andrewflnr wrote: post #97
lisper wrote: post #54

Earlier quoted context omitted.

> Could you have leviathan sized animals with no phytoplankton? Yes. See e.g.: https://www.biointeractive.org/classroom-resources/how-giant... These aren't "leviathan-sized" but they could easily provide food for something that big. The base of this food chain would be chemosynthetic bacteria. After that, energy is not the limiting factor on size.

Broadly, yes, but chemosynthetic organisms tend to be benthic (afaict, IANA marine microbiologist), so they can stay close to their food source. So something big that feeds on them would probably be a grazer more than a swimmer. Unless, perhaps, they need to swim between vent sites or something...

So I asked my friend who knows things about marine microbiology and she was actually pretty optimistic about free floating chemoautotrophs as the base of a food web. You just need enough chemicals dissolved in the water (which I guess is how they grow them in the lab). Some other ideas we discussed were bacteria growing on suspended particles and as endosymbiotes in larger animals like the aforementioned tube worms. So yeah, leviathans are on the table.
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