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

nature.com

181–190 of 754 posts

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

#181
post #27

Earlier quoted context omitted.

Yup, for several hundred thousand year's journey. No problem. :-) I would just hope my emacs session will stay up that long.

Interstellar tramp.

There are moments of pure beauty in the universe.

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

#182
post #21
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.

If pixie dust is plutonium and unicorn farts are tetradeuterium-methane, you could get there in 400 years or so, Earth-time, 398 years shipboard time.

So you really need your pixie dust to be antimatter, and your unicorn farts to be terawatt lasers.

For now, the wait calculation suggests that anyone leaving now will reach their destination after someone who waits to leave until after the next breakthrough in space propulsion technology.

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

#183
post #153
post #70

Earlier quoted context omitted.

I guess J.J. Abrams is somewhat forgiven for this, then: http://vignette4.wikia.nocookie.net/startrek/images/2/29/Vul... [edited for direct .jpg]

Firefox tries to download this file

works on Arch Linux FF

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

#184

Earlier quoted context omitted.

Just going that fast isn't really risky at all (assuming you don't hit anything, which isn't actually a safe assumption). The tough part is making something capable of a constant 1g of acceleration for a 7 year trip. Most of the craft we make only accelerate for the first small percent of a trip. We can do accelerations that high, but not for very long, and we can't even manage acceleration for such a long duration e…

My layman's reading of physics-for-layman books has taught me that if we were to travel at the speed of light, we'd convert into energy. However, I'm not so sure about 99.999999% the speed of light. That's really OK, as far as we know?

As far as we know, as long as you don't actually reach light speed (which is currently thought to be impossible anyway) you can pretty much get as close as you want and be fine.

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

#185
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…

> 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/

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

#186

So, who do we call to make sure the newly discovered planets are named Chimay, Orval, Westvleteren, Rochefort, Westmalle, Achel, and La Trappe?

40 light years = 12.2 parsecs.

I mean I feel like an opportunity was missed here...

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

#187

This news is very interesting but how is this different than any of the recent planet discoveries? Anyone mind explaining the significance of this discovery over the others?

7 is a very high number of planets in an odd system overall.

https://en.wikipedia.org/wiki/List_of_multiplanetary_systems

PS: Note the above systems may have many planets we don't know about.

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

#189
post #99

Earlier quoted context omitted.

Actually they are fewer. A dim star has less high energy radiation and a lower probability of harmful solar flares.

More radiation = more mutations = healthier/faster evolution!

Then the surface of stars ought to have more life than planets.

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

#190
post #49
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)

2000 saturn v rockets sounds possible

the fusion bit not (yet) so much though
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