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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

#151

Post by dotnet00 »

syspec wrote: post #78
HenryBemis wrote: post #63

Earlier quoted context omitted.

And when 'zooming in' and seeing the top 2/3 of the photo ( https://www.esa.int/var/esa/storage/images/esa_multimedia/im... ) I am super amazed that all these small discs showing are galaxies. GALAXIES (sorry for the caps). How tiny are we (Humans, Earth, Solar system)... less than a speck of dust in the Sahara. I used to look up in space when I was growing up and there wasn't any light pollution to the small town I…

Experience that all the time with the same imagery, with the same amazement / horror combination. What's more amazing is when you share this fact to most people "did you know each dot here is a GALAXY, not a star!" they go "heh... interesting" and shrug. For some reason that makes the whole thing even crazier to me

I think it just doesn't really click for people most of the time. Eg for my mom no amount of showing science pics and explaining the scale of the distances conveyed things, it only really clicked when Jupiter became visible in the night sky as a particularly bright and large point of light which caught her interest, and when we moved to somewhere dark enough that the galactic plane was faintly noticeable.

Re: Webb captures iconic Horsehead Nebula in unprecedented detail

#152

Post by kouru225 »

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 don’t think visiting it would be very interesting. It’s a giant dust cloud that would probably be unnoticeable from any close perspective.

Re: Webb captures iconic Horsehead Nebula in unprecedented detail

#153

Post by xandrius »

the_af wrote: post #49
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…

> it's hard not to get all philisophical and wonder about the size of space & time on cosmic scale Indeed! Never a bad time to re-watch Cosmos and (in my opinion) the awesome sequel(s) by Neil de Grasse Tyson. Is it weird to admit I even choke up during some of the episodes? (As an aside, why is it so hard to find the sequels to Cosmos in any streaming service. In my country it's not on Netflix, Disney+, Apple, HBO/M…

You gave it a fair shot, go ahead and come join us at the bay where the grass is green, the videos full HD and nobody wants your money (just your soul).

Re: Webb captures iconic Horsehead Nebula in unprecedented detail

#154

Post by xandrius »

travisjungroth wrote: post #20
kibwen wrote: post #8

Earlier quoted context omitted.

Of course there are other lifeforms out there, it's statistically implausible for it to be otherwise. What's also implausible is that, given the impossible vastness and hostility of interstellar space, that any will ever manage to contact us, specifically. Fortunately, we've got lots of crazy lifeforms here on Earth to keep us occupied, if we can take a moment to stop extincting them as fast as we possibly can.

I do think there’s other life out there. But just considering the other side, the statistical model only applies if the existence of life is actually stochastic. If a farmer plants a single tree in the middle of a square mile plot and rips up anything else that grows, any Fermi approximations done by the tree are going to be quite misleading.

Who's this galactic farmer you're talking about?

Re: Webb captures iconic Horsehead Nebula in unprecedented detail

#155

Post by mynameishere »

nilkn wrote: post #133
sandworm101 wrote: post #122

Earlier quoted context omitted.

We may not know the exact size at the start, but we know it was infinitesimally smaller than it is today. So the size of the initial universe isn't a big factor in the equations about how big it likely is today. Weather it started as a few centimeters across or a few thousand light years across, both are functionally zero compared to the current size.

We don’t know that, though. Consider an evolution of a flat coordinate plane given by (x,y) -> (e^t * x, e^t * y). This process can run forever and has the property that all points appear to move away from all other points through time, yet the size of the plane never changes. It’s better to think of the Big Bang as describing a point in time rather than a point in space.

Does anyone know why wolframalpha is plotting this with cute little arrows?

https://www.wolframalpha.com/input?i=plot+%28x%2Cy%29+%3D+%2...

Re: Webb captures iconic Horsehead Nebula in unprecedented detail

#156

Post by jjbinx007 »

HenryBemis wrote: post #63
itishappy wrote: post #10

Wow. The NIRCam image is probably going to be the most exciting new photo, but I can't get over how well MIRI reveals the internal structure of the nebula. NIRCam: https://www.esa.int/ESA_Multimedia/Images/2024/04/Horsehead_... MIRI: https://www.esa.int/ESA_Multimedia/Images/2024/04/Horsehead_... Comparison: https://www.esa.int/ESA_Multimedia/Images/2024/04/Slider_Too...

And when 'zooming in' and seeing the top 2/3 of the photo ( https://www.esa.int/var/esa/storage/images/esa_multimedia/im... ) I am super amazed that all these small discs showing are galaxies. GALAXIES (sorry for the caps). How tiny are we (Humans, Earth, Solar system)... less than a speck of dust in the Sahara. I used to look up in space when I was growing up and there wasn't any light pollution to the small town I…

Cosmic horror is a good one. I've only seen the Milky Way with my own eyes a couple of times and the last time gave me an existential cosmic horror too.

I went to sleep thinking about the unignitable size and age of what's all around us in every direction, but particularly that I had just looked at our own galaxy... a galaxy that has been there for billions of years, has always been there my entire and is there right now and there's only this tiny invisible thin bit of atmosphere separating us from it.

Then I thought about the fact tha our solar system is orbiting it right now, and we're orbiting the sun on an invisible track, and the moon orbits us on its own invisible track too.

That's quite a lot to deal with when you only woke up for a pee in the middle of a night in a camping holiday in Wales.

Re: Webb captures iconic Horsehead Nebula in unprecedented detail

#157

Post by mvkel »

dotnet00 wrote: post #136
mvkel wrote: post #112

Earlier quoted context omitted.

Fascinating. Do you think it's possible that we can map these out in the next 50 years?

For the gravitational wave background, maybe with LISA we might be able to get a glimpse, but the neutrino background seems like it'd take some truly unprecedented breakthroughs in our ability to detect neutrinos to have any chance of mapping it out.

Funny, in reading up on both, I had higher hopes for the gravitational waves.

It seems like GWB is a superposition of infinite overlapping waves that would be impossible to single out and "unwind" in order to form a map.

And big bang neutrinos are very weak, which makes them undetectable. My assumption was we'd need a breakthrough in measurement sensitivity but is there more to it?

Re: Webb captures iconic Horsehead Nebula in unprecedented detail

#158

Post by glenstein »

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.

>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

My understanding is that, at the largest scales, clusters of galaxies are organized along a series of gravitationally bound filaments, sometimes called the cosmic web.

So they aren't distributed like random noise, but more like a web. I have no reason to think this changes anything about calculating average densities, but it is notable that there's the general density but probably a significantly different density within that structure.

Re: Webb captures iconic Horsehead Nebula in unprecedented detail

#159

Post by brcmthrowaway »

danielovichdk wrote: post #119

When I look at these images I instantly and fully understand why we are interested in the universe. It is such an incredibly thing. Absolutely astonishing.

For this to exist and me shunting JavaScript around from place to place.. whats the point?

Re: Webb captures iconic Horsehead Nebula in unprecedented detail

#160

Post by tobias2014 »

HenryBemis wrote: post #63
itishappy wrote: post #10

Wow. The NIRCam image is probably going to be the most exciting new photo, but I can't get over how well MIRI reveals the internal structure of the nebula. NIRCam: https://www.esa.int/ESA_Multimedia/Images/2024/04/Horsehead_... MIRI: https://www.esa.int/ESA_Multimedia/Images/2024/04/Horsehead_... Comparison: https://www.esa.int/ESA_Multimedia/Images/2024/04/Slider_Too...

And when 'zooming in' and seeing the top 2/3 of the photo ( https://www.esa.int/var/esa/storage/images/esa_multimedia/im... ) I am super amazed that all these small discs showing are galaxies. GALAXIES (sorry for the caps). How tiny are we (Humans, Earth, Solar system)... less than a speck of dust in the Sahara. I used to look up in space when I was growing up and there wasn't any light pollution to the small town I…

To fuel your cosmic horror: Some of the dots may even be galaxy clusters
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