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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

#631

Post by cellover »

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…

I am wondering how it could affect our psyche if we were able to gaze on a mirror world with our own eyes in broad daylight. This is the first VR application I would think of: display an Earth like planet in the sky and see how it affects us.

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

#632

Post by Jaruzel »

stevewilhelm wrote: post #589
jameshart wrote: post #389

Earlier quoted context omitted.

Importantly, that means there is basically no way that a civilization that developed on such a planet would not at some point endeavor to travel to those other planets.

> no way that a civilization that developed on such a planet would not at some point endeavor to travel to those other planets. That seems like a very human statement. One could argue for a civilization to succeed it must be content with living on its home planet. And as a result, it would take good care of it.

You must be new here [on planet Earth].

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

#633

Post by wildpeaks »

cellover wrote: post #631
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…

I am wondering how it could affect our psyche if we were able to gaze on a mirror world with our own eyes in broad daylight. This is the first VR application I would think of: display an Earth like planet in the sky and see how it affects us.

That's exactly the premise of the (good) movie Another Earth: http://www.imdb.com/title/tt1549572

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

#634

Post by BinaryIdiot »

nradov wrote: post #606
BinaryIdiot wrote: post #336

Earlier quoted context omitted.

To be fair kinetic bombardment is stupid easy to do once you can put stuff into orbit. Put a few, 20 foot long tungsten rods into orbit and you can effectively nuke, without radiation, any location that you orbit over [1]. Sure this is a problem but it's one that already exists today, not necessarily only when we start building space craft in orbit. [1] https://en.wikipedia.org/wiki/Kinetic_bombardment

Kinetic bombardment is silly and inefficient science fiction. Conventionally armed ballistic missiles can strike any point on Earth almost as quickly at a far lower cost and with greater survivability.

Well today sending a rocket up, putting these things in orbit and then dropping them would probably be a bit obvious and inefficient. But in the near future when we're mining asteroids? As long as they can be captured closed enough to Earth I would imagine kinetic bombardment would be pretty effective. They would be rather difficult to shoot out of the sky as ballistic missiles can be blown up prior to reaching target but kinetic would require an much, much larger amount of energy to destroy enough so as to not hit and damage the target.

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

#635

Post by madarco »

dcposch wrote: post #496
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…

> 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. this reminds me of one my favorite films ever. it is just four minutes long http://www.erikwernquist.com/wanderers/

It reminds me of Land and Overland by Bob Shaw:

"The setting for the trilogy is a pair of planets, Land and Overland, which orbit about a common centre of gravity, close enough to each other that they share a common atmosphere."

They don't share a common atmosphere, but I guess the delta required for interplanetary transfer is really low.

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

#636

Post by jlebrech »

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)

wouldn't it be better to plot a course where pitstops could be made at gas giants?

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

#638

Post by StreamBright »

Exofunctor wrote: post #471
maverick_iceman wrote: post #446

Earlier quoted context omitted.

Lots of good reasons to establish a space colony, fleeing the earth is not one of them. By this sort of argument you actually discredit the idea of space exploration.

> fleeing the earth is not one of them Why not? If a big asteroid is going to hit earth (for example), fleeing is a pretty reasonable response. It's also a reasonable defense against technobiological hazards.

The chance that an asteroid hitting Earth that actually matters is extremely low. It is even lower chance that we can detect it on time. It is much higher chance that politicians will start a nuclear war that wipes out most of humanity from the face of Earth.

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

#639

Post by RugnirViking »

Jaruzel wrote: post #632
stevewilhelm wrote: post #589

Earlier quoted context omitted.

> no way that a civilization that developed on such a planet would not at some point endeavor to travel to those other planets. That seems like a very human statement. One could argue for a civilization to succeed it must be content with living on its home planet. And as a result, it would take good care of it.

You must be new here [on planet Earth].

Alternatively the parent considers the human race to either not have succeeded or to be in the process of changing to take good care of it

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

#640

Post by kk_cz »

irusri wrote: post #620

I cant understand what can we possibly achieve from this type of explorations. NASA spends lot of money each year to excite us but nothing really achieved. Personal thought: Isn't worthy to spend this money for alleviation of poverty in this planet?

it's ~65$ per person per year. I am not American but if I were I would gladly give 65 bucks a year for some space related excitement.
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