Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

Two potentially life-friendly planets found orbiting a nearby star

nationalgeographic.com

Post reply on HN
Print view View original

341–350 of 391 posts

Re: Two potentially life-friendly planets found orbiting a nearby star

#341

Post by 0xffff2 »

jbattle wrote: post #251
0xffff2 wrote: post #234

Earlier quoted context omitted.

>Let's say the origin of life is a million to one filter, and the successful development of sentience is another million to one filter. Those are actually pretty high odds for those two events, and the combination of those two togehter is enough to make it likely we're alone in the Milky Way. The Drake equation has 7 terms. When it was first proposed, all but the first were complete unknowns. We're just barely starti…

We should be able to make some approximations regarding sentience. If we only consider Homo Sapiens Sapiens, then yeah we only have one data point. If we consider other extinct hominid species, we have more. If we consider dolphins, ravens, etc - we start to have a fuller picture and can make some (at least slightly) informed estimates to that term

You're still extrapolating from a single life-creation event. Until we find a second planet that evolved life entirely separately from Earth, we have exactly zero meaningful information about the genesis of life. Without knowing what percentage of life is roughly similar to life on Earth, we have exactly zero meaningful information about how valid Earth-centric extrapolations are.

Re: Two potentially life-friendly planets found orbiting a nearby star

#342

Post by dwaltrip »

codesushi42 wrote: post #339
dwaltrip wrote: post #331

Earlier quoted context omitted.

You misinterpreted the comment. They were discussing a single star system with multiple habitable planets. If more than one planet in the system gave rise to an intelligent species that develops a civilization, things would likely get very interesting very quickly.

Not likely. Even traveling to a planet as "nearby" as Neptune by conventional means would take 12 years. Hardly within shooting range, and who knows whether our civilization will survive long enough for us to make it to even the edge of our solar system. And the OP was referring to a nearby star system, within "sublight year" range. Even < 1 light year could mean very, very far away.

They are referring to a single system... Here is the quote:

>> And to think that there is likely an Easy Mode system out there.

>> A habitable planet on the low end of the mass spectrum needed for a stable atmosphere with other habitable planets in-system. And all that close to another star with habitable planets, possibly in the sub-lightyear range.

Yes, they mentioned another star system as an additional point, but that wasn't the main idea.

> Hardly within shooting range

Mars is only 6 months away. We have the technology today to launch boulders weighing hundreds of tons to Mars. Those make for pretty good weapons.

Re: Two potentially life-friendly planets found orbiting a nearby star

#343

Post by dang »

corodra wrote: post #86
lmm wrote: post #30

Earlier quoted context omitted.

> I know it's nearby on galactic scales but it's practically about 450,000 Earth years away with current technology :-) If we had the political will, the Orion design could get people there in, what, 200 years, and that's with '70s technology.

"What if I told you that your family and your next 4 generations of offspring will live on a space ship that'll hopefully reach a distant planet without encountering a massive malfunction due to age or some cosmic phenomenon that'll kill you all? And if that planet is habitable for human life, hopefully it won't have terrifyingly violent lifeforms that'll rape you in the mouth so they can reproduce. Are you intereste…

Please don't post like this here.

Re: Two potentially life-friendly planets found orbiting a nearby star

#347

Post by m_mueller »

Dylan16807 wrote: post #296
nurettin wrote: post #220

Earlier quoted context omitted.

Do you acknowledge the fact that interstellar travel entails more than just speeding up and slowing down? Because that's what Dyson would be telling you if he were here.

You need a nuclear-powered airtight bunker that can sustain dozens of people, but that's also buildable with 70s technology. Once you have propulsion and a ship you're pretty well there.

One of the main unsolved problems is the electromagnetic shielding, both front and back (as you need to turn to decelerate). Even at 0.08c every speck of interstellar dust has enormous impact energy, far worse than the radiation of your own bombs. AFAIK this is unsolved.

Re: Two potentially life-friendly planets found orbiting a nearby star

#348

Post by xenadu02 »

thfuran wrote: post #315
rdm_blackhole wrote: post #306

Earlier quoted context omitted.

> While finding intelligent life would be great, finding any life is nearly as great. That would actually be worrisome. If we found and detected microorganisms on nearby planet e.g 12 light years away from earth, then that means we are probably headed for extinction. The reason is the theory of the Great Filter. Given that we have not been able to observe any kind of activity outside of our solar system, it means tha…

Have we done anything that we'd be able to detect from 12 ly?

The window for detection at different power levels is probably quite small.

Very early radio would be somewhat weak. The middle phase of analog transmission probably has some higher power levels. The digital phase would coincide with rapid decreases in detectability.

That assumes every planet capable of supporting life a) has life and b) develops intelligent life. If only 1% of planets capable of supporting life develops life and only 1% of those develop intelligent life then it is extremely unlikely these two nearby planets would have any life at all. Even if you bump the odds to 10% or even 33% the odds are still against it.

For sake of argument assume we (or they?) won the lottery and intelligent life exists. Make an even larger stretch and assume that life is technologically capable, has been for 10,000 years, and didn't destroy themselves (achieving a stable population size and reasonable resource usage). Even then the odds are against us detecting any kind of radio transmissions.

Re: Two potentially life-friendly planets found orbiting a nearby star

#349

Post by 8note »

svd4anything wrote: post #328
corodra wrote: post #100

Earlier quoted context omitted.

This is also assuming A) Human engineering can create something that can last 200+ years of space travel. We don't even build houses anymore that can feasibly last 100 years. 2) People don't go mad and kill each other or do a mutiny III) Any number of stray objects from asteroids to rogue planets that just slams into the ship and causes major malfunctions d) Food and life support sustainability I mean... there are SO…

> d) Food and life support sustainability Could we just send frozen embryos of humans and then have the ship auto thaw and gestate them 16 years to arrival? With another 2-300 years of technological progress this doesn’t seem outlandish mission at all.

that sounds highly unethical. none of those people agreed to go on the trip

Re: Two potentially life-friendly planets found orbiting a nearby star

#350

Post by matt-attack »

CondensedBrain wrote: post #167
entropea wrote: post #154

Earlier quoted context omitted.

What are the chances that would've already happened given how long we've been sending life made RF off the planet? A 24 year exchange isn't awful.

12 light years is a long way for a signal to go without attenuating into noise.

What about things like LIGO? It can detect changes in length corresponding to 1/10,000th the width of a proton. Surely communicating over RF with another planet should be within our reach, no?
Post reply on HN