My god, it's full of STARS!
April 15, 2019 9:44 PM   Subscribe

In astrophotography, the longer your camera's shutter is open, the more light you get. Five amateur astrophotographers challenged themselves to capture a world-record exposure. Result: The 1060-hour Large Magellanic Cloud

Be sure to click through to the "full version" (Image 1, Image 2) and then wait for the image to fully load. The image is a mosaic made of 16 smaller fields of view, which stitched together form a 14400X14200 image.

That's 204 million pixels or an array of Retina Display MacBook Pro screens, at full resolution, 5 wide and 8 high.

That's going to take a while to download and display.

It's worth the wait.

For the curious:
posted by flug (43 comments total) 100 users marked this as a favorite
 
Whoah! So colorful! This picture actually managed to change my conception of space!
posted by xammerboy at 10:07 PM on April 15, 2019


When grabbing the full-size images it's worth using Save Link As, then looking at the saved files with a proper photo viewer, rather than just opening them in the browser and then attempting 1:1 zoom. Browsers are often not very good at rendering parts of very large photos at full resolution.
posted by flabdablet at 10:15 PM on April 15, 2019 [17 favorites]


Have you ever looked at the sky, I mean, really looked at the sky?
posted by flabdablet at 10:29 PM on April 15, 2019 [8 favorites]


The sky-map.org view of this area lets you see various sky survey views of the area (infrared, H-Alpha, etc) and also identify some objects in the area shown on the hi-res photos by moving/clicking the mouse.

sky-map.org beta identifies a LOT more of the individual objects by name or ID number, especially if you zoom in a bit, but unfortunately the click-to-identify part is broken (broken URLs just need "server7." typed at the beginning of them FYI and then they work fine).

So you can identify, for example, NGC 2048, NGC 1763, NGC 2018, NGC 2077etc.
posted by flug at 11:12 PM on April 15, 2019 [4 favorites]


Not a sky guy, but that literally made me gasp.
posted by Alvy Ampersand at 11:14 PM on April 15, 2019 [2 favorites]


That’s my new phone lock screen, thanks.
posted by Bloxworth Snout at 11:54 PM on April 15, 2019 [2 favorites]


Goes into random wallpaper folder after some clip because HUGE!
one of the good things about my upcoming trip is middle of nowhere and dark skies... oh how I've missed you...
posted by zengargoyle at 12:05 AM on April 16, 2019


these would make sick album covers
posted by JimBennett at 12:20 AM on April 16, 2019


"The nitrogen in our DNA, the calcium in our teeth, the iron in our blood, the carbon in our apple pies were made in the interiors of collapsing stars. We are made of starstuff." - Carl Sagan
posted by Fizz at 3:45 AM on April 16, 2019 [14 favorites]


I was really struck by the beauty of the image, but more than that I was really impressed with the amateur collaboration. It's like citizen science. Love it!
posted by whalabi at 3:57 AM on April 16, 2019


So how many cups of coffee is that?
posted by RolandOfEld at 4:14 AM on April 16, 2019


For anyone else who was wondering about "Observatoire El Sauce au Chili", it is not the Chili Sauce Observatory, but rather an observatory in Chile named "El Sauce" ("the willow tree" in Spanish). I was a little bit disappointed too.
posted by ITheCosmos at 4:36 AM on April 16, 2019 [12 favorites]


Man. Thanks for sharing that link, yesterday of all days. I sent it to my (Catholic, sky-watcher) dad.
posted by eirias at 4:42 AM on April 16, 2019 [2 favorites]


Goes into random wallpaper folder after some clip because HUGE!

Many, many wallpapers worth. Select the darkest portion of that image, then zoom to that selection. Bright with stars!
posted by filtergik at 5:16 AM on April 16, 2019 [2 favorites]


So, uh, there's a lot of stars in that image. Which, you know, makes me feel properly small etc. But, are most of them in front of the cloud things, or behind, or a mix or what? Because if the stars are in our galaxy, and the clouds are yonder then that's a whole other scale of huge wow etc.
posted by seanmpuckett at 5:17 AM on April 16, 2019 [1 favorite]


Great post, thanks!
posted by salvia at 5:55 AM on April 16, 2019


if the stars are in our galaxy, and the clouds are yonder then that's a whole other scale of huge wow etc.

The LMC is "only" about 160,000 light years away from us. Many of the light sources visible within those lovely images will be things far, far further away than that.
posted by flabdablet at 6:42 AM on April 16, 2019


It looks like a bunch of jelly fish
posted by bowmaniac at 6:58 AM on April 16, 2019


Cosmic jellyfish!
posted by sarcasticah at 7:13 AM on April 16, 2019


The best kind!
posted by bowmaniac at 7:14 AM on April 16, 2019


The advances made in stacking astrophotographic images are really amazing. Instead of taking one long exposure and hoping that the image isn't ruined by sensor noise / random vibrations / passing airplanes, you take lots of little exposures and then "stack" them in software. Because of the way digital image sensors work you can basically just add the pixels together between the images and get something very close to what a long exposure or a bigger light collecting mirror would have achieved.

I first learned about stacking as a tool to get better images of planets. Someone with $800 of gear in their back yard can make a better picture of Jupiter or Saturn than anyone on earth could have made in the 1990s. It's neat to see the same techniques applied to other astronomical features.

I'm jealous of the Southern hemisphere with its view of the Magellanic cloud. I've been that side of the planet three times in my life but somehow have never managed to even see them. I guess we northerners have to make do with the Andromeda galaxy.
posted by Nelson at 8:06 AM on April 16, 2019 [5 favorites]


Have you ever looked at the sky, I mean, really looked at the sky?

Yes, any number of times and some under dark skies. But often enough ? Never.
posted by y2karl at 8:44 AM on April 16, 2019


I love that the galaxy cluster we're in is designated the "local group".
posted by bonobothegreat at 8:52 AM on April 16, 2019 [1 favorite]


I'm at work so can't really delve into it, but will definitely do it at home later; very reminiscent of the Hubble Deep Fields, some of my favorite astrophotography images.
posted by TedW at 9:58 AM on April 16, 2019 [1 favorite]


I'm jealous of the Southern hemisphere with its view of the Magellanic cloud. I've been that side of the planet three times in my life but somehow have never managed to even see them.

Any clear moonless night from my back yard. Coalsack Nebula too.

I was born and raised in the city; it was home, and that's the only reason it took me forty years to move out of it. But every time I pull up outside my place on a clear night and look up as I get out of the car, I'm so so happy I did.
posted by flabdablet at 10:21 AM on April 16, 2019 [5 favorites]


Worth noting that last time I visited my home city I was flat out finding the fifth star in the Southern Cross, and the Pleiades were gone completely.
posted by flabdablet at 10:43 AM on April 16, 2019


It literally took my breath away. Does anyone else's brain get obsessed with the gas clouds? the more i stare at them the more my brain tries to "solve" the pattern to be able to translate it into a 3D object and find the light source, shadows, transparency, etc. The same goes for regular clouds, staring at them and making the switch from "2d blobulous background" to "very tall semi-transparent bumpy surface with caves and edges" fills me with the most mind-numbing sense of awe.
posted by FirstMateKate at 10:44 AM on April 16, 2019 [4 favorites]


Since I think the grains of sand comparison is always worth repeating:

An average grain of sand is about 0.5mm across. If they're in a perfect grid, that means 8,000 grains in a cubic centimeter. They settle more compactly than that, so call it 10,000 on the low end.

If you've got good eyes and go out on a clear night a couple of hundred miles from any cities, you might be able to see 10,000 stars in the sky. For most of us, it's more like 3,000 or less. When you look up and see a whole lot of stars, that's less than the number of grains of sand in a cubic centimeter.

Take a handful of sand. You've got about 500,000 grains. If you counted them out loud it'd take you two weeks going 24 hours a day, but don't bother, we've got a long way to go if we're counting stars.

Put the handful of sand in a wheelbarrow. Now fill the wheelbarrow with sand. This will take about 3,000 handfuls, so you may want to block off the afternoon.

You've filled the wheelbarrow with sand. Great! Do it again. Now you've got 3 billion grains of sand. This is the number of stars in...the Small Magellanic Cloud, not the one we see here. We'll need another 18 wheelbarrows to get to 30 billion, which is the star count for the Large Magellanic Cloud (pictured in the OP).

Wheelbarrows are too small; we need something bigger. A dump truck of the sort you might see at a construction site or gravel pit carries 10 cubic yards. That's around 75 billion grains of sand with our numbers, or two and a half Large Magellanic Clouds. Two dump trucks gets us to 150 billion, on the low end of the estimate of the number of stars in the Milky Way.

Some galaxies have a lot more stars than the Milky Way, some have less. Let's assume the Milky Way is roughly average size. Now, for each grain of sand in those two dump trucks, get another two dump trucks full of sand.

Have we reached the number of stars in the visible universe? No, but we're at about five percent, which is pretty good! (at least 2 trillion galaxies * 150 billion stars each) There are literally more stars in the universe than grains of sand on every beach in the world put together.

Thanks, Carl Sagan!
posted by echo target at 10:51 AM on April 16, 2019 [17 favorites]


Beautiful looking at our neighbors! See, we are the scum at the bottom of some incredible pond!
posted by Oyéah at 11:07 AM on April 16, 2019 [1 favorite]


What a gorgeous image! I'm jealous, and I hope they publish a bunch of papers based on it!

"The nitrogen in our DNA, the calcium in our teeth, the iron in our blood, the carbon in our apple pies were made in the interiors of collapsing stars. We are made of starstuff." - Carl Sagan

Yes - most of those clouds are either a massive star in the process of dying (blowing off its outer layers in winds, before ultimately going supernova) or the remnants left behind by their cataclysmic deaths. That's how the medium is seeded with the heavier elements that are needed to make apple pies and people...

(Take a look at these periodic tables by Jennifer Johnson - and the paper.)
posted by RedOrGreen at 11:07 AM on April 16, 2019 [2 favorites]


Random tip: if you're trying to use ImageMagick's `convert` to `-extract` a region from these huge files and it fails with a "cache exhausted" problem... the magick is in '/etc/ImageMagick-6/policy.xml'. It took me way to long to find out that IM has a global resource limit. You may also have to set $MAGICK_TMPDIR as well.

Anyhow, I'm now generating a bunch of random regions. 
perl -e '
$x=3200;$y=1800;$ox=14400-$x;$oy=14200-$y;
for$i(0..99){
printf"convert -extract %dx%d+%d+%d %s foo%02d.jpg\n",
$x,$y,int(rand($ox)),int(rand($oy)),
"Downloads/photo95fb.jpg",$i;
}' | sh
posted by zengargoyle at 11:08 AM on April 16, 2019 [4 favorites]


I first learned about stacking as a tool to get better images of planets. Someone with $800 of gear in their back yard can make a better picture of Jupiter or Saturn than anyone on earth could have made in the 1990s

That's a different kind of stacking. It's lucky imaging - you only pick the frames of a series of very short exposures where by good luck the atmosphere is behaving particularly nicely and you get a really sharp image of the nice bright planet.

In contrast, deep imaging you stack all the images you can get for every photon you can, and you go for as long an exposure as you can tolerate still in order to minimise read out noise.
posted by edd at 6:30 PM on April 16, 2019 [2 favorites]


"The nitrogen in our DNA, the calcium in our teeth, the iron in our blood, the carbon in our apple pies were made in the interiors of collapsing stars. We are made of starstuff." - Carl Sagan

And the gold and platinum? From neutron star mergers / collisions!
posted by jjj606 at 6:33 PM on April 16, 2019


Wow. Just. Wow.
posted by SecretAgentSockpuppet at 6:54 PM on April 16, 2019


> But, are most of them in front of the cloud things, or behind, or a mix or what?

One reason I posted the sky-map links above is that you can click on various objects there and (particularly in the "beta" version) get object identification and, when available, info such as distance.

So, based on doing some of that, what I noticed:
  • There are a handful of foreground stars, maybe 5-10? They tend to be about 500 or 600 light years distant. That puts them squarely in our galaxy. They are mostly the very brightest stars in the image, bluish in color and they look like larger disks or circles on the image than the smaller, most distant "pinprick" sized stars.
    • The reason you don't see more stars & objects like nebula and star clusters from our galaxy, is because the Milky Way Galaxy is basically a thin disk (like a pancake) and the LMC, being near the south celestial pole, is pretty close to straight "down"--that is, perpendicular to the disk of the Milky Way. Between us and the LMC is only a relatively small portion of the Milky Way, and so only a few stars. If you look towards the center of the Milky Way, or anywhere into its main disk--which is easily visible in dark skies as the "Milky Way" you will see tons of bright nebula, dark nebula, star clusters, and so on very similar to those we see in the LMC. But since we are looking about 90 degrees away from the Milky Way when we look at the LMC, there are not many such Milky Way objects in this direction typically. Again, I don't think any of the nebula, star clusters, etc we see in this image are in the Milky Way--all are in the LMC.
  • All of the "cloud things" (nebula) that I could identify were at basically the same distance as the Large Magellanic Cloud, about 160,000 light years. Same goes for things like star clusters in the image. So basically all of those things are part of the LMC. They are probably orbiting in various places in/around/throughout the LMC just like similar structures in our galaxy are.
    • In short, all of the "small stars" in and around the cloudy looking area, and the nebula and star clusters you can see around the image, are part of the LMC galaxy.
  • I'm sure there are some more distant deep space objects in the image somewhere, such as distant galaxies. These would normally be at distances of millions to billions of light years from us--so MUCH further than the LMC--and so will appear a lot smaller and dimmer than the LMC. I didn't happen to notice any of these in the image but if you were to find some it would likely be by scouting around carefully in the darker, emptier areas of the image and looking for very small, irregular, relatively objects. It's possible there are few or none visible because dark dust and the like from the LMC is blocking them in this region of the sky. Also, looking at a few star charts of the region I didn't see any distant galaxies marked. That doesn't mean there are NO such galaxies here, but it likely means there are no really obvious ones.
    • All of the big, noticeable nebula, stars, star clusters, etc that you see in the image are part of the LMC (other than a few bright Milky Way stars that are much closer than the LMC). Nothing really big and noticeable is wildly more distant than the LMC.
  • The LMC is close enough to be able to resolve individual stars from it, and if you zoom into various LMC regions so can see lots and lots of these--generally small like pinpricks.
TL;DR: It seems that you are looking mostly at objects that are part of the Large Magellanic Cloud (LMC), which is about 160,000 light years distant, with just a smattering of closer stars that are within the Milky Way proper and that are generally several hundred light years distant. There are probably some distant galaxies and such in there somewhere (millions to billions of light years distant) but they are small, dim, and pretty unnoticeable if they are present at all.

TL;DR was too long, too: Your looking at mostly LMC objects.
posted by flug at 11:13 PM on April 16, 2019 [1 favorite]


This is absolutely glorious, thank you.
posted by ZipRibbons at 12:24 AM on April 17, 2019


Sooo... no one else is getting a redirect to localhost on these links? (the http://www.cielaustral.com links) It's happened on my phone, in both Brave & Firefox, and now on the laptop, in Brave, FF, and Chrome. A few users on Imgur seem to be having the same issue, but... no one else here is? Weird.
posted by quinndexter at 12:46 AM on April 17, 2019


quinndexter - same here, I guess they just realised their server was getting hammered and did that for some quick mitigation.

content's been archived by the wayback machine, tho (a, b, c).
posted by russm at 1:43 AM on April 17, 2019 [2 favorites]


That makes sense. Thankyou russm!
posted by quinndexter at 2:26 AM on April 17, 2019


Anyhow, I'm now generating a bunch of random regions.

perl -e '
$x=3200;$y=1800;$ox=14400-$x;$oy=14200-$y;
for$i(0..99){
printf"convert -extract %dx%d+%d+%d %s foo%02d.jpg\n",
$x,$y,int(rand($ox)),int(rand($oy)),
"Downloads/photo95fb.jpg",$i;
}' | sh

On the feeble one-lunged laptop I'm using right now, after editing the ImageMagick config to make it work at all, convert is still very slow: 
time convert -crop 1920x1080+300+300 large-magellanic-cloud.jpg im-lmc1.jpg

real    0m10.346s
user    0m5.396s
sys     0m2.600s
I have no desire to wait quarter of an hour for it to squeeze out a hundred of those, so I turned to ffmpeg instead: 
n=100 w=1920 h=1080
split=split=$n crop= map=()
for ((i=0; i<n; i++))
do
    split+="[i$i]"
    crop+=";[i$i]crop=$w:$h:(iw-$w+1)*$RANDOM/32768:(ih-$h+1)*$RANDOM/32768[o$i]"
    map+=(-map "[o$i]" -q:v 2 "$(printf lmc_cropped_%03d.jpg $i)")
done
time ffmpeg -y -loglevel error -i large-magellanic-cloud.jpg -filter_complex "$split$crop" "${map[@]}"

real    0m27.617s
user    0m12.724s
sys     0m4.032s
which is not too shabby for a hundred crops on this box.
posted by flabdablet at 4:30 AM on April 17, 2019 [3 favorites]


Thanks for the breakdown, flug. So instead of looking through a bug spattered windshield at a bunch of clouds in the distance, the windshield is pretty clear, and (the analogy breaking down completely) the bugs are birds near the clouds.

I wanted a sense of scale, and I think I got it.
posted by seanmpuckett at 6:22 AM on April 17, 2019 [2 favorites]


Klapaucius screamed for the machine to stop. It did, but the damage was done. Up in the sky, especially, there were only a few, isolated points of light. Gone were the wonders that had been there before: the worches, the pritons, the gruncheons, the zits…
posted by otherchaz at 7:46 AM on April 17, 2019 [3 favorites]


Pretty sure I spotted at least three worches and what might be a gruncheon in those images. But I guess they might just be jpeg artifacts.
posted by flabdablet at 8:36 AM on April 17, 2019


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