from Hacker News

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

by luxpir on 9/12/23, 7:03 AM with 141 comments

  • by _nalply on 9/12/23, 10:16 AM

    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.

  • by dotancohen on 9/12/23, 7:55 AM

      > 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?

  • by Gys on 9/12/23, 8:50 AM

    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.

  • by mpreda on 9/12/23, 9:08 AM

    We can expect these posibilities: 1. no life 2. simple life 3. advanced intelligent civilization

    In the first two cases, we need to send a physical probe there. In the third case it might be enough, and much faster, to send communication signals there and get answers back. The third case is also arguably the most interesting.

  • by perihelions on 9/12/23, 7:57 AM

  • by yashasolutions on 9/12/23, 10:50 AM

    When I read such PR it feels that someone need a budget approved and no accountability : "here is something cool that nobody can check, but hey we could explore this for a couple of millions, can you sign down here"

  • by truculent on 9/12/23, 8:29 AM

    If the presence of dimethyl sulphide is confirmed, what would the next steps be? Presumably sending a probe would not be feasible in any foreseeable timeframe?

  • by thibran on 9/12/23, 8:54 AM

    Time to build a railgun in space and get some probes to K2-18 b.

  • by dvh on 9/12/23, 7:49 AM

    K2-18 is a flare star.

  • by mg on 9/12/23, 10:33 AM

    120 light years away.

    If there was life out there, similar to us - could we detect their radio and television signals over this distance?

  • by rbanffy on 9/12/23, 9:32 AM

    I am more optimistic about the gas giant in the same system and its satellites.