Re: Expedition to Europa

On 02/07/2024 06:25, Jan Panteltje wrote:

On a sunny day (Mon, 1 Jul 2024 17:03:32 -0700) it happened Don Y
<blockedofcourse@foo.invalid> wrote in <v5vg4n$1a4s7$1@dont-email.me>:
 

But you (we) are still constrained by your knowledge of physical sciences
(and "interstellar civilizations").  Who's to say that "they" haven't
identified some other observable (by THEM) characteristic of civilization?
>
There are a whole slew of questions that you have to consider before you
even worry about "how" to detect (or signal to) other civilizations.
- how much (effort/cost) do you want to detect them?
- how much do THEY want to be detected?
- how can they evade detection (assuming they actively don't want to be found)?
- how much do YOU want to be found?
- what might the consequences of such a detection be?  (e.g., _Remembrance..._
posits an extinction level consequence)

  And will our religious fanatic polly-tick-sians and leaders let us know IF life has been detected?
The Mars Viking lander experiment was positive for life.
  http://www.gillevin.com/
I remeber the annoucement,
hours later it was plainly denied, experiment never to me mentioned again..

That was because they realised pretty quickly that what they were seeing was an inorganic reaction of peroxide and perchlorate ions in the soil with the nutrients provided. The next generation search for life on Mars will use stable isotopically labelled materials and stands a pretty good chance of detecting anything that is alive or nearly so.
There are hints that just maybe something is alive on Venus (unlikely as this sounds) phosphine has been detected in its atmosphere.
https://www.nytimes.com/2020/09/14/science/venus-life-clouds.html
--
Martin Brown