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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

#621

Post by FlorianRappl »

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/

Wonderful and inspiring. I loved the narration from Carl Sagan. One of the greatest.

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

#623

Post by mrleiter »

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.

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

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

#624

Post by arkh »

bcaulfield wrote: post #10
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…

So, basically, this is cooler than just about any world that's been depicted in sci-fi.

*Hollywood sci-fi

You get a lot more crazy worlds in written sci-fi. You can start with the Culture orbitals, some of the Commonwealth Saga worlds or Alastair Reynolds' inhibitors. If you count a neutron star with life on it, you get dragon's egg which is a must-read.

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

#625

Post by isolli »

e0m wrote: post #33

To get a spacecraft there it would take: Accelerating at 1g the 1st half, and decelerating at 1g the 2nd half, the traveler would experience 7.3 years of time. For observers it would take 41.8 years at a max speed of 0.998c If you had a near perfect hydrogen -> helium fusion engine, it'd take about 6 million tons of fuel (about the mass of the Pyramids of Egypt or 2,000 Saturn V rockets)

Isn't 0.998c unrealistic?

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

#626

Post by hansbo »

e0m wrote: post #33

To get a spacecraft there it would take: Accelerating at 1g the 1st half, and decelerating at 1g the 2nd half, the traveler would experience 7.3 years of time. For observers it would take 41.8 years at a max speed of 0.998c If you had a near perfect hydrogen -> helium fusion engine, it'd take about 6 million tons of fuel (about the mass of the Pyramids of Egypt or 2,000 Saturn V rockets)

I don't understand how it could be less than 39 years for the traveler. Time dilation is a thing, but being less than 39 years would mean the traveler observed the planet approaching faster than the speed of light, which should be impossible.

Or does space contract as well?

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

#627

Post by Zardoz84 »

cgriswald wrote: post #571
shawn-furyan wrote: post #513

Earlier quoted context omitted.

Corrections aside, it is an interesting observation that Firefly is less outlandish with this discovery (not a criticism, Firefly is optimized for fun, not scientific plausibility). Still, assuming light speed travel, Firefly's inhabited planets are still a heck of a lot closer, since the crew doesn't seem to noticeably age between the half dozen or so star systems that they visit, and don't appear to have any kind o…

> Firefly's inhabited planets are still a heck of a lot closer, since the crew doesn't seem to noticeably age between the half dozen or so star systems that they visit The 'systems' in Firefly are really all one star system. The system includes a central star orbited by planets, four other stars, and a host of "protostars" (they really mean brown dwarves). I've tried, and can't imagine a scenario where, even if such…

Proxima Centauri have a earth mass planet : https://en.wikipedia.org/wiki/Proxima_Centauri_b

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

#629

Post by MichaelMoser123 »

maverick_iceman wrote: post #434
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…

I'm wondering since these planets are so close to the parent star and to each other would it induce any gravitational instabilities?

maybe them aliens made the system up, so that it doesn't fall apart under its own gravity. Makes sense: just increase the habitable area by bringing in smaller planets into the goldilock zone - that might come out cheaper then to go interstellar.

Maybe lots of planets that circle the same star over the same orbit would be a better indicator of alien activity than a dyson sphere.

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

#630

Post by simias »

hansbo wrote: post #626
e0m wrote: post #33

To get a spacecraft there it would take: Accelerating at 1g the 1st half, and decelerating at 1g the 2nd half, the traveler would experience 7.3 years of time. For observers it would take 41.8 years at a max speed of 0.998c If you had a near perfect hydrogen -> helium fusion engine, it'd take about 6 million tons of fuel (about the mass of the Pyramids of Egypt or 2,000 Saturn V rockets)

I don't understand how it could be less than 39 years for the traveler. Time dilation is a thing, but being less than 39 years would mean the traveler observed the planet approaching faster than the speed of light, which should be impossible. Or does space contract as well?

That's correct. You wouldn't be able to do the roundrip expedition in less than 78 years from an observer's standpoint so you still can't transmit information faster than the speed of light, however from the explorer's point of view it might take a lot less time to do that as you get closer to c.

If you travel at the speed of light (assuming you're a photon or something) then time stops "existing" altogether and you are simultaneously at the point of origin, destination and everywhere in between. At least that's my understanding of it.

I find it both exciting and depressing at the same time, it means that you could potentially make a rountrip to the center of the milky way and back within a human lifetime but by the time you'll be back everybody that remained on earth would be long dead and nothing would be the same anymore. If those types of travels become common then society would stop existing on a single timeframe. It's pretty mind boggling.

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