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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

#101

Post by root_axis »

h4nkoslo wrote: post #41

Uh oh. The "great filter" hypothesis is essentially that the rarity of intelligent life has to be explained by some parameter of the Drake equation, and that whatever the "small" parameter is is either in our past or in our future. If the "great filter" is the rarity of habitable worlds, then clearly we don't need to fear it, since we already found one. But if habitable worlds aren't rare, then it's more likely it li…

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.

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

#102

Post by pvg »

sigmaprimus wrote: post #69

Based on Voyagers current speed it would take approximately 18000 years to reach this system, the referance of a jet airplane taking millions of years seemed a bit misleading, with current technology and using gravitational boosting I would think that the time could be much less. Maybe it would be worth sending a probe? Granted I will never see it in my lifetime but it might be a project I could get behind.

18k years is a very long time, though. There is a project looking at the feasibility of getting very small probes somewhere 10 times closer in perhaps decades rather than millennia:

https://www.nytimes.com/2016/04/13/science/alpha-centauri-br...

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

#103

Post by noobermin »

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…

Other awesome facts, the closest star in the habitable zone might have a "year" of a day and a half, and the furthest out in the zone, a "year" of 20 days.

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

#104

Post by VikingCoder »

DanBC wrote: post #44
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)

How much fuel would it take to get 6 million tons of fuel off Earth into the interstellar ship?

Step one, find an asteroid with ice...

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

#105

Post by twoodfin »

cletusw wrote: post #7

Apparently finds are close enough to us that we should be able "to follow up, to see, for example with the James Webb Space Telescope that we're going to launch [next] year, the atmospheres and also to look at bio-signatures, if there are any" !

Optically? That's nuts! Anyone know how this would work? Can we really expect Webb to measure light diffraction/refraction through a few miles of atmosphere on a planet 40 ly away?

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

#106

Post by [deleted] »

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…

[deleted]

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

#108

Post by [deleted] »

JumpCrisscross wrote: post #34
ionwake wrote: post #17

Earlier quoted context omitted.

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

> are there...hazards simply due to the proximity of a dim star Tidal locking [1]. Similar to how our moon shines at us ass first all the time, the planets around TRAPIST-1 would be expected to have one face locked to their star. Instead of an equatorial belt bookended with loops of temperate zones, as we have on Earth, we should expect, climatically, an "equatorial" face and a "polar" face separated by a tropic-to-t…

[deleted]

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

#109

Post by Cyphase »

sigmaprimus wrote: post #69

Based on Voyagers current speed it would take approximately 18000 years to reach this system, the referance of a jet airplane taking millions of years seemed a bit misleading, with current technology and using gravitational boosting I would think that the time could be much less. Maybe it would be worth sending a probe? Granted I will never see it in my lifetime but it might be a project I could get behind.

Unless you're talking about a Starshot-type probe, I think it's probably better to wait for improved propulsion technology that would end up arriving before a probe we sent now.
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