Earth-sized exoplanet ‘habitable zone’ • Hacker News Board

Re: Earth-sized exoplanet ‘habitable zone’

#71

Post by madrox » Wed, Jan 08, 2020, 9:26 PM UTC

AnIdiotOnTheNet wrote: post #47

madrox wrote: post #22

Earlier quoted context omitted.

Should it ever become practical to do so, the reasons for doing so will look very similar to the reasons Europeans colonized America. The thing about densely populated environments is it requires lots of governance, and populations have a habit of increasing exponentially, which would be difficult for artificial environments to keep up with indefinitely. When you're on the frontier, you have a lot more freedom.

How so? You've already become adept at living in space, working in space, and building things in space out of materials you found in space or else it wouldn't be practical at all to travel to a new star system anyway. At that point, just build new space habitats.

Apart from what's already been mentioned...

Consider that the population of England during the colonization of America was around 3 million. Today, nearly 3 times that live in London alone. It's like asking why would anyone have bothered to risk traveling across the Atlantic for months to get to untamed wilderness when England could've just built more housing.

Re: Earth-sized exoplanet ‘habitable zone’

#72

Post by ppeetteerr » Wed, Jan 08, 2020, 9:29 PM UTC

pharke wrote: post #52

fullstop wrote: post #25

Earlier quoted context omitted.

You can step outside without being in a vacuum. Have you read the Expanse books? They kind of touch on this subject.

Maybe they meant more of an O'Neill Cylinder, in which case you can step 'outside' onto the inner surface of the cylinder and not be in vacuum. Space habitats also have advantages over planets in that they're easier to move, they can be designed to not have adverse conditions like freezing cold, extreme heat and dangerous weather and you can build more of them. If you step outside of Earth's atmosphere you're in the…

That's exactly it

Re: Earth-sized exoplanet ‘habitable zone’

#73

Post by pharke » Wed, Jan 08, 2020, 9:34 PM UTC

VonBraunsGhost wrote: post #50

bazeblackwood wrote: post #46

Earlier quoted context omitted.

Wow, don't mind me, I've just never seen one of you people in the wild.

You can direct the 'you people' at yourself. I once believed in the pseudo-science promoted as truth, then I took some time to educate myself. You should do the same.

So your educated opinion is that there is a grand, generations long conspiracy involving millions of people to cover up the fact that the universe works based on magic? That sounds more like lazy thinking, if you were serious about educating yourself without relying on "mainstream science" you'd do some research that does not involve watching YouTube videos or staying up all night reading comments from random forum dwellers.

Re: Earth-sized exoplanet ‘habitable zone’

#74

Post by dotancohen » Wed, Jan 08, 2020, 9:34 PM UTC

dmurray wrote: post #15

jcims wrote: post #4

> Astronomers have discovered a world only a little bit bigger than Earth, whirling around a bright star about 31 parsecs from our planet. Parsec is one of those units that is difficult to remember if you just look at the conversion (1 parsec = 3.26 light years). If you remember how it's defined, however, it somehow becomes easier (for me anyway). One parsec is the distance at which one astronomical unit (AU, mean di…

I just remember that a parsec is the same as a light year. By astronomical standards of precision, that's about right.

  > I just remember that a parsec is the same as a light
  > year. By astronomical standards of precision, that's about right.

I just multiply them by π. Close enough, and probably on par with our measuring precision anyway.

Re: Earth-sized exoplanet ‘habitable zone’

#75

Post by cmrx64 » Wed, Jan 08, 2020, 9:35 PM UTC

dgritsko wrote: post #67

loblollyboy wrote: post #66

Earlier quoted context omitted.

What about pics from space? I see the curve. I don’t think every country is making fake pictures. Also there are plenty of amateurs with balloons and go pros and I don’t think they’re part of some grand conspiracy either. Also gravity.

Wasn't there some guy who was crowdfunding a rocket so he could go up and see for himself? Whatever became of that?

https://www.space.com/craigslist-water-heater-mad-rocket-lau...

Re: Earth-sized exoplanet ‘habitable zone’

#76

Post by basilgohar » Wed, Jan 08, 2020, 9:38 PM UTC

fastbeef wrote: post #21

dmurray wrote: post #15

Earlier quoted context omitted.

I just remember that a parsec is the same as a light year. By astronomical standards of precision, that's about right.

I remember it as 1/12th of a Kessel Run, easy peasy

The Kessel Run as performed by the Millennium Falcon; not just any ship can do that!

Re: Earth-sized exoplanet ‘habitable zone’

#77

Post by pharke » Wed, Jan 08, 2020, 9:40 PM UTC

dgritsko wrote: post #67

loblollyboy wrote: post #66

Earlier quoted context omitted.

What about pics from space? I see the curve. I don’t think every country is making fake pictures. Also there are plenty of amateurs with balloons and go pros and I don’t think they’re part of some grand conspiracy either. Also gravity.

Wasn't there some guy who was crowdfunding a rocket so he could go up and see for himself? Whatever became of that?

If they were serious they would crowdfund a cubesat and track it as it orbits the Earth. It was good enough evidence to prove that Sputnik was in orbit. You can even put cameras on the things so I'm sure there's all kinds of experiments you could do to verify that NASA wasn't faking it.

Re: Earth-sized exoplanet ‘habitable zone’

#78

Post by Mountain_Skies » Wed, Jan 08, 2020, 9:50 PM UTC

VonBraunsGhost wrote: post #57

botto wrote: post #55

Earlier quoted context omitted.

Any way we can capture one of these beings and study them, I'd love to understand how the brain works

Typical NASA fanboy response. Ad-hominem, no substance. Refute the point. You can't. No curve = no sphere

You took maybe thirty second to write your rant and demand others spend hours or maybe even weeks coming up with an entire education program to fill in the gaps you have in your knowledge. This is a huge discrepancy in effort required. Perhaps if you volunteered to do push ups for the entire time posters went through the primary school education you missed, it would be equal effort and you'd get a better reception. As it is, you're being lazy and whining that others have done the work required to understand basic science.

Re: Earth-sized exoplanet ‘habitable zone’

#79

Post by commandlinefan » Wed, Jan 08, 2020, 9:53 PM UTC

jcims wrote: post #4

> Astronomers have discovered a world only a little bit bigger than Earth, whirling around a bright star about 31 parsecs from our planet. Parsec is one of those units that is difficult to remember if you just look at the conversion (1 parsec = 3.26 light years). If you remember how it's defined, however, it somehow becomes easier (for me anyway). One parsec is the distance at which one astronomical unit (AU, mean di…

> 1 parsec = 3.26 light years

So that means that even if we could travel at the speed of light, it would still take 100 years to get there, so probably not a candidate for near-term colonization (if something bad happens to this planet, for example).

Re: Earth-sized exoplanet ‘habitable zone’

#80

Post by pushpop » Thu, Jan 09, 2020, 12:32 AM UTC

nwallin wrote: post #65

pushpop wrote: post #6

Earlier quoted context omitted.

People keep saying that for extreme climates on Earth and are then constantly surprised by the variety and abundance of life - admittedly sometimes just microbiology - found in those locations. So I wouldn’t write off a planet just for tidal lock.

The problem is that the atmosphere and weather is global. Meaning that snow that falls on the cold side will never melt or evaporate. Therefore there's probably no liquid water. Liquid oxygen is dense enough for icebergs to float over to the warm side, but there won't be any oxygen before life can start photosynthesizing, and it would boil off long before ice could float close enough to the hot side to melt or evapor…

Last year there was a discovery where some single cell organisms were extracting electrons directly from solid rock. So I don’t think ice is a barrier.

I do agree that it’s unlikely that life would exist on that planet. But I think the chances of life being slim are more down to the difficulty in the bootstrapping stage rather than the environment being too inhospitable to host life. By that I mean DNA forming (for example) might be 90% of the problem and survival might be 10%. Figures obviously made up but I hope you understand my (crudely expressed) point.

There’s also the point that extraterrestrial life might not mimic the typical examples we see on Earth. In fact in plausible for silicon and/or arsenic to be building blocks for DNA and that’s only narrowly widening our expectations of life.