All of the chemical components of DNA have now been discovered on a second asteroid. A Japanese team has now identified all of those in rocks picked up from the surface of the asteroid Ryugu. The discovery corroborates the results from a 2023 NASA mission that returned samples from the asteroid Bennu that also contained all five nucleobases. 404 Media https://www.404media.co/was-life-seeded-from-space-complete-set-of-dna-ingredients-discovered-on-asteroid/
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Was Life Seeded from Space? ‘Complete Set’ of DNA Ingredients Discovered on Asteroid

“Organic molecules delivered from extraterrestrial materials may have played a key role in supplying building blocks for life on Earth,” said one scientist.

404 Media
@adapalmer
This is fun, but It annoys me a bit how popular science reporting tries to make it more exciting, like "was life seeded from space?" I mean, maybe, but finding organic chemicals on little rocks in the solar system isn't evidence that they couldn't also form on the big rock in the solar system that we live on, and if they did, they'd be right here and not have to survive re-entry.

@petealexharris @adapalmer it leaves two possibilities, both exciting imo:
1) this is where we got our DNA, and other planets could have gotten it the same way
2) this is evidence that the building blocks for life can and have evolved on multiple rocks, making extraterrestrial life incredibly likely

of course the pessimist in me is like "ah great, now space colonists are gonna actually colonize more living beings and not just move to dead rocks"

@raphaelmorgan @adapalmer
I suspect the tricky bit of using DNA to encode heritable, evolvable proteins for life isn't getting the basic molecules. I'd really like some life to be found on Mars or Europa, and I'd expect even if it has DNA, it doesn't use the same encoding scheme as Earth life, because why would it? That'd be a data point in favour of "life is easy, it must be all over the place".
@petealexharris @adapalmer yeah it sounds incredibly unlikely that it would have the same coding scheme, and I wish I could learn more about alien genomes 🥺