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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

#301

Post by neaden »

blueprint wrote: post #72
kcorbitt wrote: post #47

Earlier quoted context omitted.

That actually sounds... more plausible than I would have expected. Like, doable with technology I can imagine being within reach in the next 50 years even if we don't achieve any currently-unforseen breakthroughs.

Which begs the question, why haven't we at least even tried to have done anything like this already? Do we really need to repeatedly spend comparable amounts of money on yet another dramatic TV special about humans traveling to Mars, as narrated by a favored celebrity? We really are running out of time. And it almost seems like it's pre-determined to happen. :\

Isn't part of the problem that any ship capable of interstellar travel is also capable of being turned into a WMD? I imagine a lot of people would get really nervous if someone for instance parked a bunch of radioactive material in low earth orbit, and even with fusion there would be the fear that someone could turn the ship around.

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

#302

Post by SapphireSun »

kakarot wrote: post #243
mtgx wrote: post #42

Earlier quoted context omitted.

I doubt we'll attempt serious inter-stellar travel before we figure out antimatter or black hole-powered engines. So we may have to wait a century or two. This century we should be more worried about making fusion-powered intra-solar system travel a common thing, and about establishing large colonies on Mars and several moons.

I don't know about all of that speculation, but you did give me a nice mental image of a barren, battle-scarred solar system littered with battleships containing black holes, ready to cause catastrophe at any moment, much like the nuclear wastelands of the Arctic.

The black hole engines he's referring to glow very hot because they're very small, meaning that the surface of the hole is large compared with its volume. This allows for very bright hawking radiation if I understand correctly. If you stop feeding them they disappear within hours, years, or decades depending on how big they are.

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

#303

Post by jonathansizz »

mkaziz wrote: post #99
rm_-rf_slash wrote: post #30

Earlier quoted context omitted.

Actually they are fewer. A dim star has less high energy radiation and a lower probability of harmful solar flares.

More radiation = more mutations = healthier/faster evolution!

That doesn't follow, at all. If we're talking about Earth-like life, then any such life would need protection from radiation to be able to live long enough to reproduce. If such protection wasn't provided by the planet's atmosphere, then life there wouldn't move out of the water. In any case, the mutation rate would need to be extremely low, as it is with Earth life.

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

#304

Post by smacktoward »

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 TRAPPIST-1 star – classified as an ultra-cool dwarf

I propose we name it "Dinklage."

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

#305

Post by dragonwriter »

idbehold wrote: post #257
logfromblammo wrote: post #238

Earlier quoted context omitted.

That's not depressing. It gives us a moral imperative to transplant Earth-origin life onto every somewhat concentrated mass that we can reach. Then we can wait a few billion years, and the universe will likely have generated a superior successor species which can then re-seed over everything we had previously tilled, and then some. And they'll all be rubber-forehead aliens to one another, because they'll be billionth…

> It gives us a moral imperative to transplant Earth-origin life onto every somewhat concentrated mass that we can reach. And in the very likely scenario that we are never able to "reach" outside our solar system... Then what?

> And in the very likely scenario that we are never able to "reach" outside our solar system... Then what?

Then we need to prepare for the Gliese 710 arrival over the next million and change years. [0]

[0] https://en.m.wikipedia.org/wiki/Gliese_710

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

#306

Post by root_axis »

idbehold wrote: post #197
root_axis wrote: post #101

Earlier quoted context omitted.

The theory as described in your link seems to hand-wave away the difficulties incumbent in the "colonization explosion" step. As it stands, intergalactic space travel (at scale) is utterly inconceivable in practical terms, and to simply assume that it is inevitable seems like a major flaw in the theory.

> then it's more likely it lies in our future (e.g. global thermonuclear war, plague, difficulty of space travel , etc) Difficulty of space travel is one of the possible filters.

Ah. I guess I was responding to

> the only thing that appears likely to keep us from [colonization explosion] is some sort of catastrophe or resource exhaustion leading to the impossibility of making the step due to consumption of the available resources (like for example highly constrained energy resources).

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

#307

Post by ant6n »

It seems that this could be an interesting system to be targeted by a FOCAL mission. It is the idea to use the sun as a large telescope by using its gravitational sense. One would have to have a telescope placed about 550 AU or so away from the sun, on the opposite side of the system you want to look at.

The magnification could be large enough to analyze features on exoplanets. My dream would be to build a telescope large enough, so that with the help of the gravitational lens of the sun we'd have a google-earth like view of the exoplanets.

http://www.newyorker.com/tech/elements/the-seventy-billion-m...

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

#309

Post by fsloth »

MrZongle2 wrote: post #133
actsasbuffoon wrote: post #114

Earlier quoted context omitted.

It would take 37 days at warp 6 (assuming we're using the new warp factors established in The Next Generation). I have no idea how much dilithium crystal would be required though.

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

Voting is a mechanism to signal whether the comment adds anything to the discussion. Star Trek references really don't add anything to an actual scientific discovery. I would much rather read actual engineering rather than entertainment driven thought.

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

#310

Post by drewrv »

drzaiusapelord wrote: post #291
blueprint wrote: post #72

Earlier quoted context omitted.

Which begs the question, why haven't we at least even tried to have done anything like this already? Do we really need to repeatedly spend comparable amounts of money on yet another dramatic TV special about humans traveling to Mars, as narrated by a favored celebrity? We really are running out of time. And it almost seems like it's pre-determined to happen. :\

The launch cost of launching the mass of the pyramids of gaza into orbit would bankrupt the richest economies. No your hypothetical engine won't be 100% efficient. This is completely unfeasible. Low mass spacecraft are our only real options. A nano-sized solar sail craft powered by the sun or lasers from Earth can hit up to 20% lightspeed theoretically and its launch costs would be affordable, if not relatively cheap…

You can't really just extrapolate the current cost of launching materials by the kilogram. A project of that magnitude would generate economies of scale and probably some innovations along the way that would bring down the cost. The "nearly perfect" fusion engine is really the hard part.
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