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Seven earth-sized planets discovered circling a star 39 light years from Earth

nature.com

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Re: Seven earth-sized planets discovered circling a star 39 light years from Earth

#711

Post by kbenson »

cstejerean wrote: post #709
kbenson wrote: post #705

Earlier quoted context omitted.

Does atmosphere include the ocean? Because life developed in the oceans first here, and some has never left.

Without an atmosphere you can't maintain a surface ocean, because liquid water can't exist in a vacuum. It's possible for the ocean to exist under a crust of ice though. See Europa for an example. So it's still theoretically possible for life to exist in a subsurface ocean, but I think it's a lot less likely compared to a planet with an atmosphere and temperatures that would support liquid water on the surface.

> It's possible for the ocean to exist under a crust of ice though. See Europa for an example.

That's exactly what I was thinking of. :)

> I think it's a lot less likely compared to a planet with an atmosphere and temperatures that would support liquid water on the surface.

Sure, but we have little information on how common life is. We're not even sure there's no life on Europa. If Europa supports life, it may be that (basic) life is somewhat common given certain criteria, and while I agree it's probably more common on planets with atmosphere and your statements were not incorrect, it may be that life is actually fairly likely on a planet like that (which is what I, possibly incorrectly, interpreted your statement as ultimately trying to convey).

Re: Seven earth-sized planets discovered circling a star 39 light years from Earth

#712

Post by pault »

dcposch wrote: post #496
dmix wrote: post #6

My favourite part of the press release: > The planets also are very close to each other. If a person was standing on one of the planet’s surface, they could gaze up and potentially see geological features or clouds of neighboring worlds, which would sometimes appear larger than the moon in Earth's sky. > In contrast to our sun, the TRAPPIST-1 star – classified as an ultra-cool dwarf – is so cool that liquid water cou…

> The planets also are very close to each other. If a person was standing on one of the planet’s surface, they could gaze up and potentially see geological features or clouds of neighboring worlds, which would sometimes appear larger than the moon in Earth's sky. this reminds me of one my favorite films ever. it is just four minutes long http://www.erikwernquist.com/wanderers/

I get a little choked up every time I watch this.

Re: Seven earth-sized planets discovered circling a star 39 light years from Earth

#713

Post by goombastic »

6502nerdface wrote: post #24

> Gillon says that the six inner planets probably formed farther away from their star and then migrated inward. Now, they are so close to each other that their gravitational fields interact, nudging one another in ways that enabled the team to estimate each planet's mass. They range from around 0.4 to 1.4 times the mass of the Earth. Given that these planets are so close to each other, and interacting with each other…

If we could do large scale engineering we would engineer something like this I suppose to increase the habitable worlds in a system.

Re: Seven earth-sized planets discovered circling a star 39 light years from Earth

#714

Post by dang »

blueprint wrote: post #320

> The launch cost of launching the mass of the pyramids of gaza into orbit would bankrupt the richest economies. Yeah… cause the way you're thinking about doing that is literally the only way in the world to accomplish the task. Not. It's not my job to qualify whether it HAS to be done to you. And even though I am the one presenting this information and this evidence, it is indeed your job to confirm it. Otherwise, y…

We detached this subthread from https://news.ycombinator.com/item?id=13708568 and marked it off-topic.

Re: Seven earth-sized planets discovered circling a star 39 light years from Earth

#715

Post by dang »

blueprint wrote: post #326

Physicists have got blinders on. Once we solve the gravity problem everything changes. I've been searching for a decade for scientists who can confirm my info but tbh most everyone seems to have abandoned themselves already.

We detached this subthread from https://news.ycombinator.com/item?id=13708611 and marked it off-topic.

Re: Seven earth-sized planets discovered circling a star 39 light years from Earth

#716

Post by dang »

maverick_iceman wrote: post #585
Arizhel wrote: post #539

Earlier quoted context omitted.

It does? Great; please point me to some instructions on how to build an anti-gravity device. I can easily build myself an electromagnet with some wire and a battery, so if our understanding of gravity is so great, I should be able to do the same with gravity, right?

What's your score?[1] [1] http://math.ucr.edu/home/baez/crackpot.html

That's a form of name-calling, which we've asked you repeatedly not to do here. If you keep doing it, we will ban you.

Re: Seven earth-sized planets discovered circling a star 39 light years from Earth

#717

Post by Arizhel »

alphanumeric0 wrote: post #710
Arizhel wrote: post #421

Earlier quoted context omitted.

You sound a little unhinged to be honest. If you're really worried that climate change on Earth is going to cause big problems for humans (which is not an unreasonable concern; climate change threatens to cause significant sea level rise which will cause big problems for people living in sea-level coastal cities), building self-sufficient colonies offworld is a rather extreme answer to that. A simpler answer is to si…

So all we have to do about climate change is build structures to handle extreme weather? Climate change is and will continue to affect our whole food chain that supports the some ~7 billion people on earth. It's not just the weather we will be dealing with.

And you think it's easier to just pack up and move to Mars than to deal with the climate change? You think it'd be easier to figure out how to grow food on Mars than to mitigate climate change-caused problems with the food chain here?

There's lots of stuff you can do to grow food here even with climate change: greenhouses, indoor/vertical farming, etc. Good luck with all that on Mars.

Re: Seven earth-sized planets discovered circling a star 39 light years from Earth

#718

Post by Arizhel »

maverick_iceman wrote: post #702
Arizhel wrote: post #698

Earlier quoted context omitted.

No one's talking about perpetual motion here. Understanding the laws of thermodynamics allows us to build heat engines, which is how many of us got to work this morning. It also allows us to build nuclear reactors (or at least the steam-cycle part of it), which is how many of us get the power to write messages here. What does our "understanding" of gravity allow us to do technologically? Nothing, because we have zero…

It's probably futile to argue with you but have you considered maglev trains?

Yes, that's an application of Maxwell's laws of electromagnetism. That's not manipulation of gravity, it's using the MUCH stronger EM force to overcome gravity.

I can overcome gravity all by myself just using my muscles to lift things. That doesn't mean that I've manipulated gravity in any way.

I'm really shocked that I seem to be the only one who groks the difference between observing a natural physical force and actually understanding it well enough to manipulate it and generate it at will. We cannot generate gravity. We can generate EM fields, and we can also generate nuclear energy by splitting or fusing atoms (which means we're manipulating the nuclear strong force, to an extent).

Re: Seven earth-sized planets discovered circling a star 39 light years from Earth

#719

Post by pault »

mrleiter wrote: post #623
MrZongle2 wrote: post #133

Earlier quoted context omitted.

Most likely several hundred quatloos' worth, I'm guessing. :D Edit: Oh, HN, you are so humor impaired sometimes.

Simply: this is not reddit. Voting happens based on the content of information added by your comment. Not a joke or a wordplay, unfortunately.

I had to downvote you because we're not supposed to compare HN to reddit. ;)

Edit: Oops, I cancelled my downvote.

Re: Seven earth-sized planets discovered circling a star 39 light years from Earth

#720

Post by grzm »

pault wrote: post #719
mrleiter wrote: post #623

Earlier quoted context omitted.

Simply: this is not reddit. Voting happens based on the content of information added by your comment. Not a joke or a wordplay, unfortunately.

I had to downvote you because we're not supposed to compare HN to reddit. ;) Edit: Oops, I cancelled my downvote.

That's a misreading of the guidelines:

If your account is less than a year old, please don't submit comments saying that HN is turning into Reddit. It's a common semi-noob illusion, as old as the hills.

https://news.ycombinator.com/showhn.html

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