First atmosphere found on Earth-like planet in habitable zone of distant star • Hacker News Board

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

#101

Post by allannienhuis » Fri, Jul 17, 2026, 5:20 PM UTC

detritus wrote: post #95

oceanplexian wrote: post #78

Earlier quoted context omitted.

> Perhaps, but it is horrifically long in terms of human stuff. Not really, unless you're obsessed with the idea that great works need to happen within your lifetime. Europe is chock full of cathedrals that took 400-600 years to build, worked on by countless generations who would never live to see them completed.

The difference there being that at the end of your day, having spent it masoning, you could leave the cathedral and go back to your family and have a walk in the fields and drink and be merry with people loved and new. The project wasn't the entiriety of your existence, it was merely the means to pay for it. Unless we have generational ships the size of small countries, I'm not sure the human brain - unaided and non-…

Generational ships would of course need to be very large, but I doubt it would need to be as large as you think. And it doesn't need to look like metal tubes. Many northern cities have extensive underground or between-building pedestrian bridges and large shopping malls, etc that can provide quite a lot of variety and the feeling of open and green spaces that is pretty attractive during long cold winters. Whether that's 'enough' to avoid mental health issues in a permanent setting is of course a different story, but that's just one of thousands of problems that would need to be solved before that ever comes close to reality :)

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

#102

Post by forinti » Fri, Jul 17, 2026, 5:22 PM UTC

andy_ppp wrote: post #14

jimbokun wrote: post #2

48 light years is in our back yard. Close enough that we could probably develop a probe to get there in the next few centuries and check it out. What are the current popular candidates for propulsion systems capable of accelerating to near the speed of light?

Probably more likely that we work out how to fold spacetime than we get there in anything like a high enough percentage of the speed of light - the fastest object we ever made travelled at something like ~0.064% * C so we are looking at ~750 years with current technology and presumably we'd need to switch on the probe in 3/4 of a millennium and figure out how to slow it down and get it into some sort of orbit around…

Universe #23: keep solar systems far enough that they can't make war on each other.

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

#103

Post by behnamoh » Fri, Jul 17, 2026, 5:23 PM UTC

fellowmartian wrote: post #65

andy_ppp wrote: post #14

Earlier quoted context omitted.

Probably more likely that we work out how to fold spacetime than we get there in anything like a high enough percentage of the speed of light - the fastest object we ever made travelled at something like ~0.064% * C so we are looking at ~750 years with current technology and presumably we'd need to switch on the probe in 3/4 of a millennium and figure out how to slow it down and get it into some sort of orbit around…

It’s highly unlikely we’re ever getting FTL. We should become comfortable with that and let go our fantasies. Let theoretical physicists chug away at this, we should get underway with projects that are possible with known science.

The entire universe seems to be inside a giant black hole, anyway, and the more it goes, the more evidence is found to support that. Might as well find a black hole and visit other universes than explore our own.

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

#104

Post by tuwtuwtuwtuw » Fri, Jul 17, 2026, 5:24 PM UTC

isodev wrote: post #71

fellowmartian wrote: post #65

Earlier quoted context omitted.

It’s highly unlikely we’re ever getting FTL. We should become comfortable with that and let go our fantasies. Let theoretical physicists chug away at this, we should get underway with projects that are possible with known science.

It would help if our science wasn’t distracted by things like global warming and nazi governments though. There are definitely ways we can help the process * right now *

Yeah, let's ignore current issues and instead focus on remote stars.

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

#105

Post by cyberax » Fri, Jul 17, 2026, 5:37 PM UTC

myrmidon wrote: post #79

kurthr wrote: post #73

Earlier quoted context omitted.

Well, there is a way to do it slowly, the probe(s) just need to be in a 500AU circular orbit. At that distance power and thrust are an issue, and RTGs seem like a better choice than solar. Certainly, takes longer to get to orbit than fly through a point for a pic, but you would get a lot more pics.

First: Orbital period out there is over 10000 years. And if you circularize (which is expensive to do in delta-v), you minimize the time window you have for observation (because you're basically pointing your speed vector straight to outside of your observation cone).

The orbital velocity at this distance is around 1 km/s, so you can fairly trivially (compared to anything else) zero it out. Then you can just hover in place, the solar gravity acceleration at this range is in _microns_ per second squared.

For all intents and purposes, you'll be in the interstellar space.

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

#106

Post by hparadiz » Fri, Jul 17, 2026, 5:41 PM UTC

neom wrote: post #96

PxldLtd wrote: post #40

Earlier quoted context omitted.

There's a project that's going well from NASA for this. Still a moonshot but they've progressed through the early stages well so far. https://www.nasa.gov/general/direct-multipixel-imaging-and-s...

Great in depth youtube video on this project: https://www.youtube.com/watch?v=go-50Dpzs20

This requires sending something to at least about 548 AU and then effect falls off from there but anything you send that far will be going at a velocity that would keep it going. You would be in effective range for some time but basically you'd need to keep sending satellites to that distance in order to keep using the technique. You'd also want to send them into different directions in order to image different parts of the sky.

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

#107

Post by mikepurvis » Fri, Jul 17, 2026, 5:44 PM UTC

Something1234 wrote: post #92

PxldLtd wrote: post #40

Earlier quoted context omitted.

There's a project that's going well from NASA for this. Still a moonshot but they've progressed through the early stages well so far. https://www.nasa.gov/general/direct-multipixel-imaging-and-s...

What would a 25km resolution of earth look like

Earth is 12700 km in diameter, so such an image would be 688 pixels across.

Basically you won't be reading license plates but you'd see enough to identify evidence of very large scale construction, and with multiple images over time I bet you could draw even more conclusions.

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

#108

Post by panagathon » Fri, Jul 17, 2026, 5:45 PM UTC

tuwtuwtuwtuw wrote: post #104

isodev wrote: post #71

Earlier quoted context omitted.

It would help if our science wasn’t distracted by things like global warming and nazi governments though. There are definitely ways we can help the process * right now *

Yeah, let's ignore current issues and instead focus on remote stars.

Scientists and engineers with an interest in such things would have an easier time working on it, if the broader economic and civic context they work in wasn't being messed with by demagogues.

They shouldn't be drafted to resolve the rise of petty tyrants. It's a waste of their time.

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

#109

Post by hparadiz » Fri, Jul 17, 2026, 5:46 PM UTC

cyberax wrote: post #105

myrmidon wrote: post #79

Earlier quoted context omitted.

First: Orbital period out there is over 10000 years. And if you circularize (which is expensive to do in delta-v), you minimize the time window you have for observation (because you're basically pointing your speed vector straight to outside of your observation cone).

The orbital velocity at this distance is around 1 km/s, so you can fairly trivially (compared to anything else) zero it out. Then you can just hover in place, the solar gravity acceleration at this range is in _microns_ per second squared. For all intents and purposes, you'll be in the interstellar space.

In order to get something there fast enough it would be traveling out very fast. Getting something there to orbit I think is not realistic for us any time soon.

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

#110

Post by poly2it » Fri, Jul 17, 2026, 5:46 PM UTC

behnamoh wrote: post #103

fellowmartian wrote: post #65

Earlier quoted context omitted.

It’s highly unlikely we’re ever getting FTL. We should become comfortable with that and let go our fantasies. Let theoretical physicists chug away at this, we should get underway with projects that are possible with known science.

The entire universe seems to be inside a giant black hole, anyway, and the more it goes, the more evidence is found to support that. Might as well find a black hole and visit other universes than explore our own.

What definition of black hole are you using?