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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

#211

Post by [deleted] »

Simon_says wrote: post #210
tunesmith wrote: post #204

I got into the Wait Calculation[1] a few weeks back and made a Jupyter notebook out of it. At our current max speed (692,000 km/hr, stated max speed of Parker Space Probe), it would take about 173,000 years to get to that planet. We could instead choose to Wait and grow our tech. By picking a constant annual growth rate and then doing some calculus to find the minimum, we can calculate the shortest possible time it w…

> taking the square root to get velocity growth rate This is your mistake. It's an approximation that works well only at low speeds.

[deleted]

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

#212

Post by Simon_says »

munherty wrote: post #208

Someone please correct me, because with a planet that is at 111 light years away aren't we technically looking back in time? Any type of observation was only a period Of time and any type of life used to be there, but may not be there presently?

Everything you look at is looking back in time.

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

#213

Post by lachlan-sneff »

ryacko wrote: post #206
lachlan-sneff wrote: post #198

There are lots of people in the comments here talking about how long it would take to send a probe, or how many generations a generation ship would have, but it seems clear to me that that's not how humans are going to go to other solar systems. Once we solve mind uploading (assuming that it's possible), we can send a blob of grey goo on a solar sail at a very high acceleration to another solar system. It can shed ha…

If we can simulate wetware perfectly, we would also be able to solve any health condition. This is all presumptive of the preferences of individual humans. It may be that the giant extrasolar Earth-type planets could be dismantled and rebuilt into smaller Earths located at various Lagrange points.

For sure, maybe future humans won't want to do that. The important takeaway is that they'll have the opportunity to do so if they wish.

They could even clone them back on the other end and install the preexisting mind, basically teleportation.

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

#214

Post by thenickdude »

partiallypro wrote: post #89
sky_rw wrote: post #76

Earlier quoted context omitted.

Not sure the two are comparable. 300lb obese person's bone structure weighs the same, their heart and lungs weigh the same. I suspect 2x the weight on every organ is going to be seriously detrimental for sustained periods.

Not to mention you'd go from years and years of near 0G gravity to twice the gravity of earth. You wouldn't even be able to walk.

If you're making this trip in any reasonable amount of time, you're probably accelerating during the journey at least half a G anyway.

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

#215

Post by grumpy8 »

cthalupa wrote: post #164
grumpy8 wrote: post #156

Earlier quoted context omitted.

Or sending a HUGE human civilization spaceship somewhere.. maybe it will outlast the earth?

In a lot of ways, living on spaceships/space stations/other artificial constructions is likely a better path forward than looking to colonize new planets in general. O'Neill cylinders are quite practical, and with advances in technology that seem likely to occur, even larger projects like Bishop rings should be doable. They can be linked together to form constellations, and have enough free floating resources within…

>> It probably sounds less than ideal to you and me, vs. living on a planet, but it probably wouldn't be so bad to someone born in that sort of environment and is used to it.

Yeah, and also at some point, it won't matter what's ideal or not.. it'll be about survival.

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

#216

Post by dyslexit »

munherty wrote: post #208

Someone please correct me, because with a planet that is at 111 light years away aren't we technically looking back in time? Any type of observation was only a period Of time and any type of life used to be there, but may not be there presently?

110 years in the past is insignificant relative to a planet's geological period's age.

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

#218

Post by Swizec »

peteretep wrote: post #180
Swizec wrote: post #22

Earlier quoted context omitted.

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 ...

I mean that sounds pretty awesome if you invested your funds well. I'd definitely be willing to be the first person who did that.

Where can you invest that would still recognize those funds as yours after 222 years?

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

#219

Post by newsbinator »

nothis wrote: post #173
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'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). I just realized I have no real concept of how many stars there even are within, say, a 100 light year radius of our sun (I guess that's a more realistic thing to find out than the number of planets). A quick search…

> That's a number where some "1% of 1% of 1%" kinda filter quickly ends up in a scenario where a planet fitting all our criteria might simply never be in reach.

It might cheer you up to think that's the only reason the human race happens to be the one in our neighborhood that made it into space, without being stepped on by an Old One.

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

#220

Post by brownbat »

manicdee wrote: post #134

Some caveats per Marina Koren https://twitter.com/marinakoren/status/1171873631808438273 1. This planet probably doesn’t have a solid surface 2. Being in the “habitable zone” doesn’t mean a planet is habitable 3. The detection is of water molecules, chances are the water only exists as vapour in the atmosphere of this small gas giant. 4. If you ask 10 astronomers about this you will get 11 opinions

> Being in the “habitable zone” doesn’t mean a planet is habitable

True. Being a spooky near twin of Earth isn't necessarily enough.

The air inside popcorn factories is basically identical to the Earth's atmosphere, but breathing in diacetyl, a butter flavor you'll find in that air, will kill you a few months or years later.

Popcorn lung really undermined my naive view that we would one day be able to run a scan or a sniff test on a planet and then just breathe without assistance.

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

You have an identical twin to Earth with slightly different dust composition and it could shred our lungs. We are highly, highly tuned to our home.

Which doesn't mean we can't go anywhere. But it won't just be advances in travel speed that will get us off world. It may also require drastic modifications to the human organism.

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