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

nature.com

401–410 of 754 posts

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

#401
post #375
post #309

Earlier quoted context omitted.

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.

I think you've just proven his point.

Yeah, I know, I might be occasionally too cynical.

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

#402

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…

Who is to say we aren't already transplants just looking to reconnect with our cousins?

[deleted]

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

#403

> The launch cost of launching the mass of the pyramids of gaza into orbit would bankrupt the richest economies. Yeah… cause the way you're thinking about doing that is literally the only way in the world to accomplish the task. Not. It's not my job to qualify whether it HAS to be done to you. And even though I am the one presenting this information and this evidence, it is indeed your job to confirm it. Otherwise, y…

I don't think the way you are arguing your points does you any favors.

Well, literallycancer, that begs the question of why nobody helps me with their ability and suggestions to argue better. I have had to do everything on my own. The way this message of mine is treated is perhaps the reason for or the reflection of the fact that mankind's usage of science and technology seem predetermined to lead to destruction. But feel free to ignore me. Everyone does whatever they want regardless of their reason, facts, or personal truths, anyway.

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

#404
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 do you consider a spacecraft though. What is the payload mass ?

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

#405
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 this means all the planets are all a volcanic mess because of the tidal forces?

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

#407

Earlier quoted context omitted.

> 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…

Of course, #askNasa didn't win me a question, but could any astrobiologists comment on this question: Tidal locking means the planets would always have a side facing the star, leading to very different thermodynamics in terms of climate and weather on the planet, not to mention radiation. Doesn't that very much hurt the chances for life on those planets?

Maybe but I like to think there are creatures living in the temperate rim of a tidally locked planet somewhere debating whether life could possibly evolve on a rotating planet.

"I mean, there'd be temperature fluctuations of tens of degrees every day! It would be dark half the time! How could life survive in such an unstable environment?"

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

#408
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)

That actually sounds pretty achievable. Difficult, but all within the boundaries of known physics and existing human lifetimes.

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

#409
post #377

Earlier quoted context omitted.

According to this paper, you can travel around 0.5 c before the radiation caused by colliding with interstellar hydrogen kills you: http://www.scirp.org/journal/PaperInformation.aspx?paperID=2... "Going slow to avoid severe H irradiation sets an upper speed limit of v ~ 0.5 c. This velocity only gives a time dilation factor of about 15%, which would not substantially assist galaxy-scale voyages. Diffuse interstellar…

Couldn't you put some kind of "snowplow" on the front so it pushes the oncoming detritus away to the sides?

A reddit thread mentions that idea: https://www.reddit.com/r/science/comments/12nls5/speed_kills...

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

#410
post #185

Earlier quoted context omitted.

> 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... Makes me think of the film Another Earth http://imgur.com/a/01xlN

Melancholia by Lars von Trier is another great movie about the earth colliding with another planet. http://www.imdb.com/title/tt1527186/

Which is on Netflix for streaming. Thanks for the tip.
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