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Water found on a potentially life-friendly alien planet

nationalgeographic.com

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Re: Water found on a potentially life-friendly alien planet

#21

Post by guelo »

archgoon wrote: post #4
transreal wrote: post #2

With a planet this large, visiting it would be a one way trip due to the "The Tyranny of the Rocket Equation" [0]. I'm looking forward to the day we start finding exo-planets that are closer to Earth in size and which could potentially have space-faring races (and which we could leave if we were ever to visit them). [0] - https://www.nasa.gov/mission_pages/station/expeditions/exped...

It's 111 light years away. For all intents and purposes, that's a one way trip right there; irregardless of the rocket equation. Even at relativistic speeds, you can't come home anymore.

The fastest spacecraft humans have produced is the Parker Solar Probe which when it zips around the sun will reach 430,000 mph. At that speed it would take 173,000 years to reach this planet.

Re: Water found on a potentially life-friendly alien planet

#22

Post by Swizec »

ajconway wrote: post #18
archgoon wrote: post #4

Earlier quoted context omitted.

It's 111 light years away. For all intents and purposes, that's a one way trip right there; irregardless of the rocket equation. Even at relativistic speeds, you can't come home anymore.

Theoretically, you can. At 0.99c 111 light years take about 15 years of ship time to travel.

So you can survive the trip but even if you come back home, it’s not home anymore? Imagine leaving 222 years ago and coming back now ...

Re: Water found on a potentially life-friendly alien planet

#23

Post by onemoresoop »

dopamean wrote: post #9

What makes a planet an "alien" planet?

I never encountered the term alien planet but exoplanets are planets outside our solar system. In a way all planets are alien to one another. Alien to us is anything extraterrestrial in this context.

Re: Water found on a potentially life-friendly alien planet

#24

Post by Miner49er »

gist wrote: post #19
Miner49er wrote: post #12

Earlier quoted context omitted.

Well, I suppose I'm using a bit of hyperbole. Maybe I should say sad. And don't worry, I won't think about it very long.

Why is it sad at all? What would it do for you? It would be about as relevant as being able to communicate in some way with people in the past. Would be interesting and entertaining but a leap to imagine it would yield some kind of better quality of life in the current day.

okay, maybe sad wasn't the right word either. How about disappointing?

Re: Water found on a potentially life-friendly alien planet

#25

Post by typeformer »

I say let's go. Now, whether you believe it or not, it is a fact that the US government has acquired alien technology and yet continues to keep it hidden by being stuck in a cold war mindset of, "well, we can't let the Chinese or Russians get their hands on this". That is the ultimate expression of narrow thinking, especially when there is a whole universe out there!

Bring on the downvotes but history will vindicate my comment.

Re: Water found on a potentially life-friendly alien planet

#26

Post by hinkley »

transreal wrote: post #2

With a planet this large, visiting it would be a one way trip due to the "The Tyranny of the Rocket Equation" [0]. I'm looking forward to the day we start finding exo-planets that are closer to Earth in size and which could potentially have space-faring races (and which we could leave if we were ever to visit them). [0] - https://www.nasa.gov/mission_pages/station/expeditions/exped...

I made it well into this decade before I was made aware of this fact. It's kind of a shock, still. At some point your planet is massive enough that you can't get into orbit with chemical rockets (even, I think, by flying them up like Burt Rutan?).

The implications for the Drake equation are pretty big.

Rockets without any promise of ever being able to break orbit are good for what, war? Would you keep developing them? Would you give up dreams of the stars? Would you look for intelligent life you couldn't ever possibly meet?

Re: Water found on a potentially life-friendly alien planet

#27

Post by TheOtherHobbes »

transreal wrote: post #2

With a planet this large, visiting it would be a one way trip due to the "The Tyranny of the Rocket Equation" [0]. I'm looking forward to the day we start finding exo-planets that are closer to Earth in size and which could potentially have space-faring races (and which we could leave if we were ever to visit them). [0] - https://www.nasa.gov/mission_pages/station/expeditions/exped...

Surface gravity will be around 2g, so even if it has a rocky surface it's not going to be a very comfortable home from home.

Re: Water found on a potentially life-friendly alien planet

#28

Post by trianglem »

gist wrote: post #19
Miner49er wrote: post #12

Earlier quoted context omitted.

Well, I suppose I'm using a bit of hyperbole. Maybe I should say sad. And don't worry, I won't think about it very long.

Why is it sad at all? What would it do for you? It would be about as relevant as being able to communicate in some way with people in the past. Would be interesting and entertaining but a leap to imagine it would yield some kind of better quality of life in the current day.

I feel like the ideal of life existing on another planet would improve my quality of life. The additional potential would do wonders for my everyday narrative.

Re: Water found on a potentially life-friendly alien planet

#29

Post by ta1234567890 »

kadoban wrote: post #8
transreal wrote: post #2

With a planet this large, visiting it would be a one way trip due to the "The Tyranny of the Rocket Equation" [0]. I'm looking forward to the day we start finding exo-planets that are closer to Earth in size and which could potentially have space-faring races (and which we could leave if we were ever to visit them). [0] - https://www.nasa.gov/mission_pages/station/expeditions/exped...

So that's purely for a chemical rocket, right? Is there any combination of tricks that can realistically push the envelope there? For example can we use a space elevator to start higher/faster (or, I don't know, balloons? a catapult or railgun or something?), laser power delivery from the ground, so we don't have to carry all the fuel, and an orbiting way-station for refueling, etc.?

Exactly

From the reference article:

> Travelling from the surface of Earth to Earth orbit is one of the most energy intensive steps of going anywhere else. This first step, about 400 kilometers away from Earth, requires half of the total energy needed to go to the surface of Mars.

Which means that if we use something like a balloon/blimp in the first stage, it would be a lot more energy efficient.

Anyone knows why it's not done that way already?

Also, whatever happened with the plane+rocket Virgin Galactic project?

Re: Water found on a potentially life-friendly alien planet

#30

Post by cycop »

guelo wrote: post #21
archgoon wrote: post #4

Earlier quoted context omitted.

It's 111 light years away. For all intents and purposes, that's a one way trip right there; irregardless of the rocket equation. Even at relativistic speeds, you can't come home anymore.

The fastest spacecraft humans have produced is the Parker Solar Probe which when it zips around the sun will reach 430,000 mph. At that speed it would take 173,000 years to reach this planet.

Great! , do that gravity assist a few more hundred times around the sun and we are there in 500 years.
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