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Comment by cbm-vic-20 | Hacker News Reader

Incredible. If each of those galaxies has on average a few hundred billion stars (our is estimated to have between 100b-400b), and each of those little dots is an entire galaxy, well, that's a lot of stars in this image.

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People use the term mind-blowing loosely but it really fits here. That’s an utterly astounding, incomprehensible number of stars.

And this image is “roughly the size of a grain of sand held at arms length” of the night sky.

a brief peek into infinity

Not really - there is a fairly definite ending about 13.4b light years into the image.

I think you're referring to the age of the universe here? But due to inflation, although the universe is 13 billion years old, the observable universe is quite a bit bigger than that (i.e. we can see stars much further than 13 billion light years away).

I was thinking of the age - good point.

> And this image is “roughly the size of a grain of sand held at arms length” of the night sky.

For a more specific measurement: NASA says 2.4 arcminutes across[0].

[0]: https://webbtelescope.org/contents/media/images/2022/038/01G...

Lots of planets, too. Some, with life.

Or maybe not. If you consider how improbable is the origin of life on the earth then maybe it's not even enough planets in the observable universe to start a life. But the universe is much greater than its observable part.

What is the probability of life originating on earth?

We know it is anywhere from 0 (originated elsewhere and found its way here) to 1 (originated here and is guaranteed to originate given the conditions). I don't think we have enough data points to determine improbability yet.

What is the probability of life originating in the universe? We know it is definitely greater than 0..

you may like to read about the "rare earth" hypothesis and the "fine tuned universe" theory.

Do you have some books or articles you could suggest?

Call me gen Z but I prefer my knowledge in video form. Can highly recommend PBS Spacetime's coverage of the topics: https://www.youtube.com/channel/UC7_gcs09iThXybpVgjHZ_7g

Humanity has found aminoacids in asteroids. Given enough time and energy, it seems likely to me that structures would form and then evolve in complexity.

Agreed. I realized recently that planets not only need a goldilocks configuration but likely also need to have a liquid metal core to create a protective magnetic field.

It would still occur quite a bit, and some planets with a protective field likely still produce simple life forms.

Since we're looking at objects billions of light years away, we're looking billions of years into the past. In the context of extragalactic life, it's a bit sad to me that even if we somehow spotted it at those insane distances, in the early versions of those galaxies we see, odds are that it'll be gone by now, and we'll likely be gone by the time any lucky photons born in our solar system can reach those places, too. Even so, it's cool to think that the odds of life being out there somewhere in a universe so vast are really quite good, inaccessible as it may be.

Bro everything other then the alive is out there and all the aliens are on earth your just not capable of seeing them

Everything without life is out there the ones with life are all on earth yo NASA spends all its money on how to lie

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