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First atmosphere found on Earth-like planet in habitable zone of distant star

bbc.com

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Re: First atmosphere found on Earth-like planet in habitable zone of distant star

#311

Post by globular-toast »

creesch wrote: post #283
globular-toast wrote: post #271

Earlier quoted context omitted.

Project Hail Mary does a pretty good job, although probably doesn't come across in the film. SF that doesn't even bother using wormholes or some other FTL travel (e.g. warp speed) is quite annoying, though.

I mean, even there they pretty use the Astrophage as a plot device to fill in the huge gap in technology needed to cover those distances. They make it clear that they would have no chance to cover those distances without the Astrophage, but it is very convenient.

Sure, it's fiction. But at least there is a device.

Re: First atmosphere found on Earth-like planet in habitable zone of distant star

#312

Post by palata »

stasomatic wrote: post #306
palata wrote: post #304

Earlier quoted context omitted.

You can downvote me as much as you want, but that's a genuine question: there are more species on Earth than any of us know. Before hoping to find new animals on new planets, why not caring about what's on ours?

No downvote from me, but - Aren't the undiscovered ones just different colored insects or jellyfish? I mean, it's a cool job if you get paid for it to discover new things that can kill us fast in the Amazon. I think we can leave them alone to do their thing and concentrate on team Human. Money better spent. I'd be terrified to meet an alien. Very much doubt they'd be attractive purple skinned humanoids like in the ST…

> Aren't the undiscovered ones just different colored insects or jellyfish?

I was answering to someone saying that they would dream of seeing animals from another planet. Pretty sure that they (like everybody else) cannot list 0.01% of the insects out there.

If one is interested in animals, there is more to discover on Earth than what they can realistically do in their whole life. Being interested in alien animals feels like "I don't actually care about animals, but I find the idea cool".

Re: First atmosphere found on Earth-like planet in habitable zone of distant star

#313

Post by micromacrofoot »

creesch wrote: post #141
micromacrofoot wrote: post #135

Earlier quoted context omitted.

500+ years, and it would likely need to be inert for most of that trip, space is big

Try 74 832 years actually.

I was being a little optimistic with theoretical designs that could happen within our lifetimes (nuclear pulse at 10% c gets ~500), but yes absolutely true that with current tech it's tens of thousands even with the rosiest of estimates

add in a bunch of complication for "oh wait, you need to stop too"

Re: First atmosphere found on Earth-like planet in habitable zone of distant star

#314

Post by bluGill »

eaenki wrote: post #290
creesch wrote: post #280

Earlier quoted context omitted.

You are not wrong, but it still wouldn't make a whole lot of difference. First of all with any technology we currently have, including hypothetical proposals, we can't even get close to 1c. The best we can do, and this assumes purely hypothetical unproven ideas, is accelerate to a fraction of the speed of light. Acceleration itself will take up a significant amount of time and even then we are nowhere near the speed…

Man, that’s not how intelligence works. Eventually if a civilization doesn’t blow itself up, it will achieve anything, and it’s not incremental steps. Speed has never been incremental steps. in 1810 you would’ve been thinking about faster horses or some shit like that. Def not rockets. OP said hundreds of years. In hundreds of years from now our rulers will definitely have that kind of tech, whatever tech it is.

Often technology is approaching an asymptotic limit that it will not go beyond. Know about a hand waving will change the laws of physics. There's every reason to believe that the speed of light is a maximum that we will never be able to choose because it requires infinite energy. While it is true we don't know everything, and there are certainly parts of it we don't know, the things we do know will have to obey and predict the things that we currently do know to be true. The laws of relativity, although annoying, are very good at describing things. If anything replaces relativity, it's going to replace it while still predicting exactly the same things that relatively does that we have verified. That doesn't leave much room for a theory that might and faster travel.

Re: First atmosphere found on Earth-like planet in habitable zone of distant star

#315

Post by randomImmigrant »

ant6n wrote: post #111
randomImmigrant wrote: post #44

Earlier quoted context omitted.

Note: terrestrial chemistry is no different from chemistry that can occur anywhere, given the right molecules and conditions, and even then it’s a matter of degree. Nitrogen being replaced by helium would actually be fine but for the niggling issue that we need nitrates. There are no heliates (?) to compensate. The name doesn’t even make sense… helium is the sole gas to have an ium end like metals- chemically it’s th…

Why would it be necessary for life to depend on breathing atmosphere? The atmosphere could just help in keeping the temperature even and provide some nice pressure, maybe that’s favorable over vacuum.

Simple. Energetics. Gaseous exchange has many energetic benefits that you give up if you have a mostly inert atmosphere.

If all your reactive chemistry comes from water/minerals, you’re also a heck of a lot more tethered, as both these cycle slower than the atmosphere.

A dynamic atmosphere is a huge component of the energetic efficiency of life on earth. And while it’s totally plausible other chemistries can match this, what’s implausible is for no chemistry to match it.

And when it comes to complex life on earth, it literally didn’t happen till oxygen percentages got sufficiently high in the atmosphere, a two billion year long process set off by Cyanobacteria. You can’t get big bodies if you can’t get this kind of energy.

Re: First atmosphere found on Earth-like planet in habitable zone of distant star

#316

Post by bluGill »

jfyi wrote: post #93
baron816 wrote: post #9

Earlier quoted context omitted.

Interstellar travel is probably not ever going to happen. Even if we have antimatter propulsion (which is still probably not practical even under ideal circumstances), we’re still talking hundreds of years of travel time to get to somewhere like this star. This also goes for aliens visiting Earth. Interstellar travel is just so impractical that I don’t think anyone has come on safari to Earth.

A generation ship is probably doable with some level of conceivable technology. We just have to figure out how to be self sufficient out there then we have all the time in the world, or universe. That's a big "just", I know.

We also need to make it last. The pyramids are not very old on a cosmic scale and the things that make them last are a dead end for spacecraft.

Re: First atmosphere found on Earth-like planet in habitable zone of distant star

#317

Post by bluGill »

palata wrote: post #312
stasomatic wrote: post #306

Earlier quoted context omitted.

No downvote from me, but - Aren't the undiscovered ones just different colored insects or jellyfish? I mean, it's a cool job if you get paid for it to discover new things that can kill us fast in the Amazon. I think we can leave them alone to do their thing and concentrate on team Human. Money better spent. I'd be terrified to meet an alien. Very much doubt they'd be attractive purple skinned humanoids like in the ST…

> Aren't the undiscovered ones just different colored insects or jellyfish? I was answering to someone saying that they would dream of seeing animals from another planet. Pretty sure that they (like everybody else) cannot list 0.01% of the insects out there. If one is interested in animals, there is more to discover on Earth than what they can realistically do in their whole life. Being interested in alien animals fe…

Problem is I'm not interested in insects. A new leader species of large mammal would interest me. Even discovering dinosaurs aren't extinct is neat but not something I'd care about.

Re: First atmosphere found on Earth-like planet in habitable zone of distant star

#318

Post by bluGill »

ErigmolCt wrote: post #278
naveen99 wrote: post #235

Habitable for silicon intelligence may be more common than habitable for carbon intelligence.

A machine civilization could probably spread into many environments that biology cannot tolerate, but it still has to be invented somewhere first

There is no particular reason to think a process for silicon life couldn't exist that starts from something like our carbon based form started. We don't know what that is, but we have ideas.

Re: First atmosphere found on Earth-like planet in habitable zone of distant star

#319

Post by BuyMyBitcoins »

deadbabe wrote: post #249
dantillberg wrote: post #117

Earlier quoted context omitted.

An even more ridiculous dream of mine: I hope that aliens build a similarly amazing telescope, point it at Earth, and share the images with us, so that we can _see_ our Earth in the distant past.

I hope they picked up dinosaurs and bred them. And maybe bring them back home! Even though our atmosphere is no longer oxygen dense enough.

I was going to make a joke about the aliens returning and presenting us with a bunch of birds.

But that got me thinking, if an intelligence goes around collecting species, how would they keep their specimen populations from evolving? How could they possibly keep so many specimens alive over the eons?

Perhaps their strategy would be to take a vast amount of genetic samples and preserve those species as data. Rather than abduct dozens of T-Rexes for some zoo exhibit, they take the genomes from tens of thousands of T-Rexes and make a population snapshot. After they depart from Earth they could clone or create as many as they want, as needed.

Re: First atmosphere found on Earth-like planet in habitable zone of distant star

#320

Post by DarmokJalad1701 »

hparadiz wrote: post #188
DarmokJalad1701 wrote: post #147

Earlier quoted context omitted.

> so it's not too different to "get there" and "orbit there". But to "get there" within any reasonable timespan requires going really fast - which is currently highly impractical. And then once you get there, you have to them cancel pretty much all of that velocity which is not just a "few percent more delta V".

We can do 7-8 AU per year right now using tech we have. Voy 1 and Voy 2 are moving at 3.59 and 3.25. A starship sized rocket could also possibly get a small payload that separates to 15 AU. This is all using conventual propellent. If you consider using nuclear explosive as a prepulsion technique the math starts to change substantially and you can achieve even 25 AU / year. https://ntrs.nasa.gov/api/citations/20140013…

Sure. But then how do you go from 7-8 AU/yr (33-38 km/s) to whatever the orbital speed is at that distance and also point that velocity vector in the correct direction for the orbit?
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