this post was submitted on 24 Sep 2023
242 points (91.4% liked)

Technology

58133 readers
4744 users here now

This is a most excellent place for technology news and articles.


Our Rules


  1. Follow the lemmy.world rules.
  2. Only tech related content.
  3. Be excellent to each another!
  4. Mod approved content bots can post up to 10 articles per day.
  5. Threads asking for personal tech support may be deleted.
  6. Politics threads may be removed.
  7. No memes allowed as posts, OK to post as comments.
  8. Only approved bots from the list below, to ask if your bot can be added please contact us.
  9. Check for duplicates before posting, duplicates may be removed

Approved Bots


founded 1 year ago
MODERATORS
 

Alien life may not be carbon-based, new study suggests::Self-sustaining chemical reactions that could support biology radically different from life as we know it might exist on many different planets, a new study finds.

you are viewing a single comment's thread
view the rest of the comments
[โ€“] PumpkinSkink@lemmy.world 21 points 1 year ago (1 children)

I mean, I can agree that simple autocatalytic reactions can occur with chemistry based on other elements... but it's a stretch to say that suggests "alien life might not be carbon-based". Maybe very, very simple, life-like chemical systems, but life as we know it is defined by large, many-atom molecules, and no other element can do this the the way carbon can (not even silicon, whose bond energy decreases with catentation of more silicon atoms link, which, combined with it's poor ability to form multiple bonds ruins the possibility of silicon-based life). Anything that we can conceivably think of as "life" beyond simple self-reproducing chemical, or bizzare Boltzmann brain-esque systems will have carbon-based chemicals in it.

[โ€“] EssentialNPC@lemmy.world 4 points 1 year ago

Thank you! I was going to make this exact point. Autocatalytic reactions are assumed with good reason to be a necessary step on the way from non-life chemicals to life, but they are only one step. Carbon is the only element that can form the basis of the huge variety of chemicals needed for the simplest of life to evolve.

When I was an undergrad, I had professors who made completing arguments that live on other planets would not only be carbon-based, but that it likely would closely resemble life on Earth on molecular, microscopic, and macroscopic levels. Survival of the fit certainly depends upon the environment, but it also must comply with chemistry and physics. I am no expert in theoretical xenobiology, but it provides a strong and fact-based counter to the idea that alien life would by default be wildly different from life on Earth.