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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

#51

Post by twoodfin »

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…

If you're going to assume heavy equipment on the other end (ours or "someone else's"), it's not ridiculously beyond our current capabilities to simply transmit DNA sequences along with enough digital training material to "grow" and raise a human population from scratch.

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

#52

Post by hcarvalhoalves »

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)

What's the math behind your estimations? Doesn't sound so unfeasible.

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

#53

Post by fsloth »

"Due to its mass, the star has the ability to live for up to 4–5 trillion years"

So when the rest of the universe cools off and stars start to die, Trappist one keeps on shining and shining... We need to get there. But first, let's get rid of our genocidal tendencies.

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

#54

Post by verandaguy »

ionwake wrote: post #17
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?

Depending on the spectrum of the star, I would be concerned about non-visible radiation doses when in close proximity to the star.

IANA astrophysicist, though.

Actually, adding onto that, I'm wondering whether orbits this tight would result in a noticeable centripetal force -- that is, that you'd feel lighter on the night side of the planet than on the day side.

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

#55

Post by shireboy »

vkou wrote: post #21
ionwake wrote: post #5

Earlier quoted context omitted.

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 )

At a constant 1g of acceleration, you could travel there, from the traveler's point of view, in ~2-3 years. (And in ~40 years from a stationary observer's point of view.) Mind you, a constant 1g acceleration (Or accelerating any human-carrying spaceship to relativistic speeds, really,) is about as plausible as a spaceship driven by pixie dust and unicorn farts.

You would just blow by it though. If you wanted to stop there, your ship would have to turn around and aim the unicorn farts forward to decelerate you 1g the second half of the trip, bringing the time to ~7-8y

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

#56

Post by Sharlin »

pm90 wrote: post #38
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)

What if we used engines powered by nuclear energy (fission or fusion)? Could we reduce the amount of fuel, since the energy density is so much higher?

The GP already posits a theoretical perfect fusion drive.
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