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NASA says distant exoplanet could have rare water ocean, possible hint of life

theguardian.com

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Re: NASA says distant exoplanet could have rare water ocean, possible hint of life

#61

Post by _nalply »

1. I looked up the phase diagram of water. If the mass is 10 times the earth, their athmospheric pressure might be one hundred times of ours. At that pressure, water boils at about 300°C. If ambient temperature is about 200°C then their chemistry would be completely incompatible with ours. And with hydrogen athmosphere anyway.

2. Re the Dark Forest hypothesis: maybe. They will discover our radio in about 60 years (assuming that our broadcasting only started to be strong enough to notice 60 years ago). Then they might assemble something like a robotic attack army and send it over after, let's say 10 years. And if they are capable to send something half the light speed, then we might encounter our demise after 240 years more. So we still can enjoy our Earth 300 years or more if we don't destroy our livelyhood basis on Earth ourselves before that. Perhaps we could retaliate and send something back, but probably the odds are bad.

3. However there's the Loud Aliens And We Are Early hypothesis as well: maybe. There's life on that planet but not as advanced as ours. We will find more signs of life the next decades in that case. Then maybe send several robot probes. Contact could be possible after: 30 years of building the first probe, sending it over: 600 years (assuming we can reach 20% of light speed) and first reporting back 120 years, in total 750 years.

Caveat emptor: This is all speculation.

Re: NASA says distant exoplanet could have rare water ocean, possible hint of life

#62

Post by melvinmelih »

rowanG077 wrote: post #29
pomtato wrote: post #27

Earlier quoted context omitted.

so you're implying speed atleast 10x the speed of light? i think you'll have better luck increasing the human lifespan instead.

Not that's not what he is implying. He is talking about time dilation.

How does one travel 1000 light years in a span of human lifetime (~80 yrs) if you’re not going faster than the speed of light?

Re: NASA says distant exoplanet could have rare water ocean, possible hint of life

#63

Post by raverbashing »

kypro wrote: post #24
King-Aaron wrote: post #15

Earlier quoted context omitted.

> The good news: if there is intelligent life it will not easily get here either. Unless 'it' left a long time ago and is already here. I always feel the 'space is big haha no one can cross it' argument is weird due to always framing it in our own frame of reference. What if the hypothetical 'thing' is like a jellyfish and time isn't as big an issue, or an AI that definitely doesn't care about time. Or a bundle of fu…

The thing I always found a bit unnerving is that if they've left and are traveling at a speed close to the speed of light we'd never know until they arrive. If something is traveling at the speed of light towards us (whether a ship or a death star laser) we wouldn't know until it arrived. Now we've been sending radio signals for several decades you have to begin to question if there's a civilisation out there maybe 1…

Most likely explanation? You can't travel at close (even 1%) of the speed of light without dealing with interstellar gas compression, object collision, passing through any moderately strong magnetic field without deviating, etc

Re: NASA says distant exoplanet could have rare water ocean, possible hint of life

#64

Post by londons_explore »

raverbashing wrote: post #63
kypro wrote: post #24

Earlier quoted context omitted.

The thing I always found a bit unnerving is that if they've left and are traveling at a speed close to the speed of light we'd never know until they arrive. If something is traveling at the speed of light towards us (whether a ship or a death star laser) we wouldn't know until it arrived. Now we've been sending radio signals for several decades you have to begin to question if there's a civilisation out there maybe 1…

Most likely explanation? You can't travel at close (even 1%) of the speed of light without dealing with interstellar gas compression, object collision, passing through any moderately strong magnetic field without deviating, etc

I suspect future people will solve these problems.

Re: NASA says distant exoplanet could have rare water ocean, possible hint of life

#65

Post by dividedbyzero »

_nalply wrote: post #61

1. I looked up the phase diagram of water. If the mass is 10 times the earth, their athmospheric pressure might be one hundred times of ours. At that pressure, water boils at about 300°C. If ambient temperature is about 200°C then their chemistry would be completely incompatible with ours. And with hydrogen athmosphere anyway. 2. Re the Dark Forest hypothesis: maybe. They will discover our radio in about 60 years (as…

> Then they might assemble something like a robotic attack army and send it over

Why would they want to though? What do we have here that someone who could do the above couldn't get much easier otherwise?

Re: NASA says distant exoplanet could have rare water ocean, possible hint of life

#66

Post by _joel »

dotancohen wrote: post #3

> the agency also hinted at even more remarkable possibility in the > potential finding of a molecule called dimethyl sulfide (DMS), which > on Earth is only produced by life. Are there any other instruments or telescopes that could further investigate this? Or is JWST the only telescope instrumented to detect such molecules 120 LY far away?

It's not really "seeing" them but the absopbtion of light in certain wavelengths that shows what's present in the exoplanet's atmosphere. There's a whole new branch of sience looking for bio and techno signatures from exoplanets. Exciting times!

Re: NASA says distant exoplanet could have rare water ocean, possible hint of life

#68

Post by _joel »

Gys wrote: post #11

Distance is 120 light years. So whatever we see is 120 years in the past. Getting there within a reasonable time frame is impossible with our current technology (an unmanned rocket will still needs 1000s of years). The good news: if there is intelligent life it will not easily get here either.

> if there is intelligent life it will not easily get here either.

We made need to redefine intelligent life if we think of ourselves as the pinacle of intelligence or rather in the upper eschelons.

Re: NASA says distant exoplanet could have rare water ocean, possible hint of life

#69

Post by pharmakom »

dividedbyzero wrote: post #65
_nalply wrote: post #61

1. I looked up the phase diagram of water. If the mass is 10 times the earth, their athmospheric pressure might be one hundred times of ours. At that pressure, water boils at about 300°C. If ambient temperature is about 200°C then their chemistry would be completely incompatible with ours. And with hydrogen athmosphere anyway. 2. Re the Dark Forest hypothesis: maybe. They will discover our radio in about 60 years (as…

> Then they might assemble something like a robotic attack army and send it over Why would they want to though? What do we have here that someone who could do the above couldn't get much easier otherwise?

To ensure that we don’t do the same.

Re: NASA says distant exoplanet could have rare water ocean, possible hint of life

#70

Post by kawzeg »

melvinmelih wrote: post #62
rowanG077 wrote: post #29

Earlier quoted context omitted.

Not that's not what he is implying. He is talking about time dilation.

How does one travel 1000 light years in a span of human lifetime (~80 yrs) if you’re not going faster than the speed of light?

Time dilation! Time is relative. For an outside observer, over 1000 years pass, but aboard the ship, much less time passes. There are calculators for this, e.g. at [0]. If you constantly accelerate at 1g, flip around at the halfway point and accelerate in the opposite direction for the rest of the journey, roughly 13 years would pass from the traveler's perspective.

This site also has a "Newton's universe" mode, which pretends that relativity doesn't exist. Interestingly, in that case you would take over 44 years!

[0]: https://www.omnicalculator.com/physics/space-travel?c=EUR&v=...

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