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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

#11

Post by jxcole »

ionwake wrote: post #5
bcaulfield wrote: post #2

Let's go

It's a Trap ;) On a serious note, if we can travel close to the speed of light , say 95%, using for example, nuclear rockets, how long would it take to arrive ? ( from the travellers perspective )

It's 39 light years so no fewer than 39 years from our perspective. The closer to the speed of light the travelers are the less time will appear to have elapsed from their perspective. If you had rockets that could instantaneously accelerate to infinitessimally close to the speed of light, no time at all would appear to have elapsed from the travelers perspective (or no time that they would notice), but this is very unlikely.

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

#13

Post by NickBusey »

rubicon33 wrote: post #9

I was reading up about earth alternatives recently, and upon realizing the distance was always going to limit us, no matter how perfect the planet, I realized we need to travel at the speed of light. I think our "best shot" at that right now, is to digitize humans. If we could store consciousness in binary, we could then transmit it at the speed of light (like we do with data every day!). You'd need a receiver on the…

Why not just make that first payload contain actual humans? Seems a helluva lot simpler.

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

#14

Post by kchoudhu »

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…

Is this an orbitally stable arrangement?

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

#15

Post by trcollinson »

ionwake wrote: post #5
bcaulfield wrote: post #2

Let's go

It's a Trap ;) On a serious note, if we can travel close to the speed of light , say 95%, using for example, nuclear rockets, how long would it take to arrive ? ( from the travellers perspective )

Well it is approximately 40 light years away from our solar system. So the basic calculation would say about 42 years but this doesn't account for acceleration and deceleration and such.

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

#17

Post by ionwake »

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…

Out of interest , although dimmer, are there any potential hazards simply due to the proximity of a dim star?

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

#18

Post by jff »

petrikapu wrote: post #12

Three of those discovered planets are in habitable zone https://www.dropbox.com/s/bdeog7ta7i4rb7c/alien%20planets.pn...

Are you basing that statement purely on the appearance of the planets in the artist's conception you linked, or was it stated in another article somewhere?

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

#19

Post by desireco42 »

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…

Those cool stars are also very durable and will not burn that easily.

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

#20

Post by rubicon33 »

NickBusey wrote: post #13
rubicon33 wrote: post #9

I was reading up about earth alternatives recently, and upon realizing the distance was always going to limit us, no matter how perfect the planet, I realized we need to travel at the speed of light. I think our "best shot" at that right now, is to digitize humans. If we could store consciousness in binary, we could then transmit it at the speed of light (like we do with data every day!). You'd need a receiver on the…

Why not just make that first payload contain actual humans? Seems a helluva lot simpler.

You could, and probably would. But, how would you send everyone else? That 'traditional' method (carbon based fuels to propel a heavy payload) is extremely expensive, and slow. So if you ever wanted to send more than just 1 payload, you'd quickly reach resource limitations (namely cost, and time).
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