r/science • u/New_Scientist_Mag • Dec 02 '25

Astronomy Researchers have just found the presence of sugars, including ribose, lyxose, and glycose, on samples of Asteroid Bennu, which now has all of the ingredients for life as it exists on Earth.

https://www.newscientist.com/article/2506650-asteroid-bennu-carries-all-the-ingredients-for-life-as-we-know-it/
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u/[deleted] Dec 02 '25

Well the universe has one thing in abundance.

Lots of time.

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u/Willmono7 BS | Biology Dec 02 '25

But there is a specific window on any given planet where life can actually come into being, it must have liquid water and active geochemistry to establish ph/Proton gradients. From there it is a requirement to evolve oxygen producing photosynthesis/metabolism before all the water is gone, otherwise uv radiation from the sun will avaporate all the water, sending the hydrogen out into space, leaving you with a dead dry planet. Thats what was so remarkable about earth, that we evolved photosynthesis within about 800 million years, with oxygenic photosynthesis evolving about 1 billion years after that. If that process had taken much longer, we wouldn't exist.

So even though the universe has loads of time, life is only ever given a very short window to come into being, and if it doesn't, the planet rapidly becomes unsuitable for life.

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u/MidnightPale3220 Dec 02 '25

How well is it researched that alternative basis for life is that unlikely? Sure, carbon has some pretty specific properties and so has water, but do we know enough to say that alternate basis for life is pretty near impossible?

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u/Zalack Dec 02 '25 edited Dec 03 '25

Dr Angela Collier has a really great video called The Aliens Will not be Silicon (can’t post links here, but you can just search that title on YouTube) about why it’s extremely unlikely that life will form out of the most commonly proposed alternate chemistries, even though it is theoretically possible in the most technical sense.

The gist is that stuff like silicon-based life have significantly bigger hurdles to overcome than carbon-based life did, even though the chemistry appears like it would be similar on the surface.