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Tryptophan, an essential amino acid, has been found to exist on #Bennu, a small #asteroid that swings by our #planet about every six years.

The discovery stems from an unprecedented sample collected by the OSIRIS-REx mission, which landed a #spacecraft on the asteroid in 2020, captured 121.6 grams of rocks and dust, and safely returned the cache to Earth in 2023.

Studying Bennu is important because its composition reflects that of the early solar system, giving scientists a glimpse into the beginnings of #life.

Finding tryptophan in the Bennu asteroid is a big deal, because #tryptophan is one of the more complex amino acids, and until now it had never been seen in any #meteorite or space sample.

The presence of tryptophan in an asteroid supports the idea that the recipe for life might not have begun only on Earth. Seeing it form naturally in space tells us that these ingredients were already being made out in the early Solar System. That would have made it easier for life to get started.

#astrobiology
edition.cnn.com/2025/11/27/sci…

in reply to Mikko Tuomi

Chances of complex amino acids like Tryptophan being destroyed when a meteorite heats during its passage through the atmosphere seem high.
in reply to Peter

@PeterLG Perhaps. The whole of the meteorite does not necessarily experience heating, and its interior might well remain intact.

I must note though, this is not something I am sufficiently familiar with professionally.

in reply to Mikko Tuomi

Tryptophan existing on an asteroid is not the same as life forming spontaneously in space. This kind of thing leads to interesting conversations about what could/could have happened, but the more mundane conversation about what has happened is too slow for a news article.
in reply to Linza

Of course it isn't. It is a discovery of a complex amino acid though, and evidence for the fact that precursors of life form spontaneously in space.
This entry was edited (1 week ago)
in reply to Mikko Tuomi

@65dBnoise hard recommend this "thinking out loud" thread by @mike_malaska

deepspace.social/@mike_malaska…

This entry was edited (1 week ago)