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Webb captures iconic Horsehead Nebula in unprecedented detail

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Re: Webb captures iconic Horsehead Nebula in unprecedented detail

#101

Post by alex_suzuki »

jll29 wrote: post #72
patates wrote: post #33

Earlier quoted context omitted.

"A lot" is the number of fish in a swarm maybe. This is so far away from our concept of counting things that the mind just gives up. There's no comparison, no dumbing down to X amount of football fields, just nothing. I find it depressing, confusing but also inspiring and fascinating at the same time.

That feeling of awe, if that could be shared with most people on earth - perhaps they wouldn't waste their pity lives fighting each other.

Wasn’t their recently an article on how witnessing a solar eclipse has a measurable effect on people’s view of the world? It certainly affected me.

Re: Webb captures iconic Horsehead Nebula in unprecedented detail

#102

Post by Barrin92 »

qwertox wrote: post #6

It's so very unlikely that there aren't millions of other lifeforms out there. Sometimes I think that life could well have been just my soul and no one else, but here I am sharing this world with billions of other people, trillions of other lifeforms on this planet alone. So it is possible that more than one lifeform exists, that they share this universe and communicate in it. Why shouldn't this also be possible on m…

>that they share this universe and communicate in it. Why shouldn't this also be possible on millions of other earth-like planets out there?

one trivial but powerful observation that von Neumann made was that our galaxy say, is actually pretty small. It's about 100k light years big, which means that any civilization spreading at only a tiny fraction of the speed of light could expand through the entire milky way in only a million years. We could very well spread through the entire galaxy in the near future if we manage to get to like, 1% of light speed in the next few hundred years.

So our galaxy, which contains a few hundred billion stars almost certainly has no other intelligent life in it for the simple reason that it'd be everywhere. That doesn't mean there's no microbial life or maybe technological life billions of light years out there but the fact that we're so alone in our neighborhood is a pretty strong indicator in the direction that advanced life might be much more rare than some people assume.

Re: Webb captures iconic Horsehead Nebula in unprecedented detail

#103

Post by layer8 »

devsda wrote: post #30

That's an incredibly detailed image. Every single time I see one of these amazing space pics, it's hard not to get all philosophical and wonder about the size of space & time on cosmic scale, how small our earth is and how insignificant our regular problems are. I don't care if I don't get to see flying cars or AGI in my lifetime but I will be very disappointed if our knowledge of space remains more or less the same…

We are lucky that we live in a sweet-spot era where the universe is old enough that we have 13 billion years to look back on, but young enough that all the galaxies haven’t receded behind the cosmic horizon yet due to the accelerated expansion of the universe. In some billion years, intelligent beings will only have historic records, if anything at all, to look back to how the observable universe used to be filled with billions of galaxies.

Re: Webb captures iconic Horsehead Nebula in unprecedented detail

#104

Post by mvkel »

sandworm101 wrote: post #71
markus_zhang wrote: post #69

Earlier quoted context omitted.

Is 2,000 billion some theoretical limit or something else? Thanks.

Yes. Take the age of the universe, multiple by the rate of expansion to get the total size of the universe, then multiple by the average density of galaxies in the observable universe. There are some further complications, but at the root it is basic algebra.

Isn't the rate of the expansion of the universe increasing?

And that assumes the observable universe is homogeneous, which it isn't

Re: Webb captures iconic Horsehead Nebula in unprecedented detail

#107

Post by layer8 »

dylan604 wrote: post #18
bloopernova wrote: post #12

Gorgeous and upsetting that I'll never be able to visit it. 13 billion years before me, potentially trillions of years after me. Seems like such a waste of the spark of awareness that I can't take that awareness and experience the galaxy in all its glory.

I have reservations for the restaurant at the end of the universe.

If you look closely at the kitchen in the background, it’s all frozen microwave food.

Re: Webb captures iconic Horsehead Nebula in unprecedented detail

#108

Post by an-honest-moose »

layer8 wrote: post #100
sandworm101 wrote: post #91

Earlier quoted context omitted.

Well, no. The density in the observed universe is used to extrapolate the number of galaxies in the non-observed universe. The size of that universe is extrapolated from the rate of expansion and the time since the big bang. The size and shape of the observable universe also changes. A moving observer, say someone doing 30% of lightspeed, will see further in one direction than another. Accelerate quickly enough and t…

As far as we know, the total universe may have infinite size, and thus contain infinitely many galaxies.

That doesn't necessarily follow - the universe can be infinite in size, but contain a finite amount of matter.

Re: Webb captures iconic Horsehead Nebula in unprecedented detail

#109

Post by zoeysmithe »

devsda wrote: post #30

That's an incredibly detailed image. Every single time I see one of these amazing space pics, it's hard not to get all philosophical and wonder about the size of space & time on cosmic scale, how small our earth is and how insignificant our regular problems are. I don't care if I don't get to see flying cars or AGI in my lifetime but I will be very disappointed if our knowledge of space remains more or less the same…

We're probably not getting to space without AGI or at least some level of sophisticated AI. At a certain point our biological bodies are just wed to the Earth and its ecosystem, as we are animals that are products of the Earth.

If "we" ever get out there, some form of mechanical AI will. And we will never know it because once we send those ships off, we'll be long gone before the return signal gets to us from some far of locale. Imagine a voyager who can self-repair, mine asteroids, print circuits, etc. Now imagine giving it a 1 million year mission. Maybe by then we'll all have given up on biology and we'd be the "robots" on that ship.

Sometimes the universe makes beings like us, but not often, and probably makes all manner of interesting beings that will most likely be forever out of reach, and us out of their reach. Kudos to some life on a faraway planet, I wish we could meet.

Also its fun to think of the universe as a system. Here's this incomprehensibly large thing constantly in motion, constantly having stars die out and explode, and new ones born, etc all the time but to us at incredible slow speeds, everywhere, yet at incredible distances from each other. Its like this bellows that keeps a fire lit, over and over, non-stop. But not quite non-stop because this great furnace too will (probably) have a proper death. This universe life cycle chart is both a feat of science and an incredible work of a permanent and grim mortality of all things.

https://en.wikipedia.org/wiki/Graphical_timeline_from_Big_Ba...

Re: Webb captures iconic Horsehead Nebula in unprecedented detail

#110

Post by layer8 »

qwertox wrote: post #6

It's so very unlikely that there aren't millions of other lifeforms out there. Sometimes I think that life could well have been just my soul and no one else, but here I am sharing this world with billions of other people, trillions of other lifeforms on this planet alone. So it is possible that more than one lifeform exists, that they share this universe and communicate in it. Why shouldn't this also be possible on m…

We don’t know how large the universe is, and how (un)likely life is. Life could very well be highly unlikely with respect to the size of the universe. We currently have no good way to tell. The only thing we know is that life is not impossible.
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