13 billion light-years from home
September 25, 2012 2:17 PM Subscribe
eXtreme Deep Field (1.4 MB JPG) is the deepest-ever view of the universe - a new assemblage of 10 years of Hubble Space Telescope photographs focused on a small area at the center of the original Ultra Deep Field. With a cumulative exposure time of 2 million seconds, XDF shows approximately 5,500 galaxies - some of them 10 billion times too faint to be seen with the naked eye.
It's galaxies all the way down.
The original deep field image is one of my favorite things, a symbol and an illustration of one of the most profound gifts that science has given us: the gift of perspective.
posted by Scientist at 2:23 PM on September 25, 2012 [10 favorites]
The original deep field image is one of my favorite things, a symbol and an illustration of one of the most profound gifts that science has given us: the gift of perspective.
posted by Scientist at 2:23 PM on September 25, 2012 [10 favorites]
This is a technically impressive photograph that has the aesthestics of a tasteful trapper keeper cover.
posted by subtle-t at 2:23 PM on September 25, 2012 [16 favorites]
posted by subtle-t at 2:23 PM on September 25, 2012 [16 favorites]
New desktop wallpaper. Awesome!
posted by slogger at 2:28 PM on September 25, 2012 [2 favorites]
posted by slogger at 2:28 PM on September 25, 2012 [2 favorites]
subtle-t: As an artist, Nature is a hack. But a very prolific one.
posted by Atom Eyes at 2:28 PM on September 25, 2012
posted by Atom Eyes at 2:28 PM on September 25, 2012
I like it, but I also think they make this shit up to scare us.
posted by colie at 2:29 PM on September 25, 2012
posted by colie at 2:29 PM on September 25, 2012
I found this, which helped me understand the scale.
posted by cgk at 2:31 PM on September 25, 2012 [5 favorites]
posted by cgk at 2:31 PM on September 25, 2012 [5 favorites]
Imagine a field, stretching to an infinite horizon. Now, make time speed.
posted by Mblue at 2:33 PM on September 25, 2012 [1 favorite]
posted by Mblue at 2:33 PM on September 25, 2012 [1 favorite]
I can't even multiply two two-digit numbers without mechanical help, so my ape brain is just gonna go ahead and interpret that as Nature's Wallpaper no matter how much I want to believe that there really are a hundred billion galaxies lying around
posted by theodolite at 2:35 PM on September 25, 2012 [6 favorites]
posted by theodolite at 2:35 PM on September 25, 2012 [6 favorites]
Look at those galaxies smudging against each other in the center top. And I think you can see gravitational lensing around the big start center bottom?
This is really fun to peer at. Even the blurry wisps imply so much hugeness.
posted by postcommunism at 2:41 PM on September 25, 2012
This is really fun to peer at. Even the blurry wisps imply so much hugeness.
posted by postcommunism at 2:41 PM on September 25, 2012
eXtreme Deep Field (1.4 MB JPG) is the deepest-ever view of the universe
Somewhere out there among the 5,500 galaxies there's someone thinking "deepest ever? I've seen deeper."
Yes, Metafilter is open to extraterrestrial membership.
posted by twoleftfeet at 2:47 PM on September 25, 2012 [1 favorite]
Somewhere out there among the 5,500 galaxies there's someone thinking "deepest ever? I've seen deeper."
Yes, Metafilter is open to extraterrestrial membership.
posted by twoleftfeet at 2:47 PM on September 25, 2012 [1 favorite]
Pretty, but practically useless. NASA should never have outsourced galaxy mapping to Apple. On Google Maps you can actually see the Federation starbases and flight paths.
posted by griphus at 2:48 PM on September 25, 2012 [12 favorites]
posted by griphus at 2:48 PM on September 25, 2012 [12 favorites]
Boggled again.
posted by flippant at 2:49 PM on September 25, 2012 [1 favorite]
posted by flippant at 2:49 PM on September 25, 2012 [1 favorite]
Oh my god, it's full of very very faint galaxies.
posted by BrashTech at 2:52 PM on September 25, 2012 [3 favorites]
posted by BrashTech at 2:52 PM on September 25, 2012 [3 favorites]
5500 galaxies in an area smaller than my thumbnail. All that time and distance and size in one little picture, and multiply that by the rest of the sky in a sphere surrounding the earth and that is a pretty humbling, if not mind-numbing concept. Very very cool and awesome.
posted by Zack_Replica at 2:52 PM on September 25, 2012 [4 favorites]
posted by Zack_Replica at 2:52 PM on September 25, 2012 [4 favorites]
5500 galaxies with maybe 300 billion stars each, that's 1.6 quadrillion stars in just a tiny fraction of the galaxy. The odds of life out there must be incredibly high, but we may never get out there to find out.
posted by CheeseDigestsAll at 3:03 PM on September 25, 2012 [3 favorites]
posted by CheeseDigestsAll at 3:03 PM on September 25, 2012 [3 favorites]
scblackman, I find it heartening. It reminds me that all those petty little concerns and embarrassments are miniscule, insignificant, and meaningless. I love that. It makes living so much easier.
I am a substitute teacher, BTW--I love showing this picture to children during a gap moment.
posted by RedEmma at 3:04 PM on September 25, 2012 [3 favorites]
I am a substitute teacher, BTW--I love showing this picture to children during a gap moment.
posted by RedEmma at 3:04 PM on September 25, 2012 [3 favorites]
Red_Emma et al, the best "petty little concerns..." image is here, even if at a smaller scale.
posted by lalochezia at 3:10 PM on September 25, 2012
posted by lalochezia at 3:10 PM on September 25, 2012
BTW this image is amazingly profound.,,,,
Also profound: that "A Flight Through the Universe, by the Sloan Digital Sky Survey" (linked by the eponysterical think_long) really shows if you've kept your laptop screen clear.
posted by lalochezia at 3:10 PM on September 25, 2012
Also profound: that "A Flight Through the Universe, by the Sloan Digital Sky Survey" (linked by the eponysterical think_long) really shows if you've kept your laptop screen clear.
posted by lalochezia at 3:10 PM on September 25, 2012
Anybody else see this guy when you stare at the image for a while?
posted by Kale Slayer at 3:11 PM on September 25, 2012
posted by Kale Slayer at 3:11 PM on September 25, 2012
Hey, is that a piece of fairy cake?
posted by Wolfdog at 3:36 PM on September 25, 2012 [5 favorites]
posted by Wolfdog at 3:36 PM on September 25, 2012 [5 favorites]
It seems that the public images aren't really that good -- the XDF, when I compare it back and forth with the largest image I can find of the Ultra Deep Field.... just doesn't seem to have all that many more visible objects.
There are more visible objects, to be sure, but with the publicly available images, I don't see a huge improvement.
Actually, unless they have a higher-res image available somewhere, the older Ultra Deep Field looks "better" (for aesthetic values of color saturation and noise, *not* from a scientific perspective because I don't have proper analysis tools) than the new Extreme Deep Field.
posted by chimaera at 3:40 PM on September 25, 2012
There are more visible objects, to be sure, but with the publicly available images, I don't see a huge improvement.
Actually, unless they have a higher-res image available somewhere, the older Ultra Deep Field looks "better" (for aesthetic values of color saturation and noise, *not* from a scientific perspective because I don't have proper analysis tools) than the new Extreme Deep Field.
posted by chimaera at 3:40 PM on September 25, 2012
an image of a small area of space in the constellation Fornax
Ah, upon RTFA, I'm guessing I'm not in this picture.
posted by eugenen at 3:56 PM on September 25, 2012
Ah, upon RTFA, I'm guessing I'm not in this picture.
posted by eugenen at 3:56 PM on September 25, 2012
This is so very beautiful. Exploration never has to end.
posted by deo rei at 3:58 PM on September 25, 2012 [1 favorite]
posted by deo rei at 3:58 PM on September 25, 2012 [1 favorite]
It seems that the public images aren't really that good
These things are 77,000,000,000,000,000,000,000 miles away. Cut them some slack, willya?
posted by Egg Shen at 4:04 PM on September 25, 2012 [2 favorites]
These things are 77,000,000,000,000,000,000,000 miles away. Cut them some slack, willya?
posted by Egg Shen at 4:04 PM on September 25, 2012 [2 favorites]
These things are 77,000,000,000,000,000,000,000 miles away. Cut them some slack, willya?
I'm very well aware of that. I'm talking about in comparison between the XDF and the UDF publicly available images. All available public images of the XDF are LOWER resolution than the highest resolution UDF images available.
If they have higher resolution images there's no reason for them not to release them. And if there are no higher resolution images, it's not actually a deeper field than the UDF, just a longer exposure.
posted by chimaera at 4:07 PM on September 25, 2012
I'm very well aware of that. I'm talking about in comparison between the XDF and the UDF publicly available images. All available public images of the XDF are LOWER resolution than the highest resolution UDF images available.
If they have higher resolution images there's no reason for them not to release them. And if there are no higher resolution images, it's not actually a deeper field than the UDF, just a longer exposure.
posted by chimaera at 4:07 PM on September 25, 2012
For reference, compare the 2 images at their highest-res available publicly (highest res from the hubblesite.org image repository):
Extreme Deep Field (2382 X 2078 JPG)
Ultra Deep Field (6200 x 6200 JPG)
You will definitely see some very dim objects that are not visible or difficult to discern (presumably due to the longer exposure) but unless they're hiding a larger image up their sleeve, the XDF is a lower angular resolution than the UDF.
posted by chimaera at 4:13 PM on September 25, 2012 [3 favorites]
Extreme Deep Field (2382 X 2078 JPG)
Ultra Deep Field (6200 x 6200 JPG)
You will definitely see some very dim objects that are not visible or difficult to discern (presumably due to the longer exposure) but unless they're hiding a larger image up their sleeve, the XDF is a lower angular resolution than the UDF.
posted by chimaera at 4:13 PM on September 25, 2012 [3 favorites]
...so the most astronomically accurate movie is actually Starcrash?
posted by hellojed at 4:58 PM on September 25, 2012
posted by hellojed at 4:58 PM on September 25, 2012
If you get an enjoyable vertigo from this, please treat yourself to this talk by George Smoot. He moves you through a galaxy space like this one around minute nine. Work up to it. Then wait for the utterly sickening scale around minutes 11 and 12, when he brings in these massive webs of dark matter with embedded galaxies.
posted by O Blitiri at 5:02 PM on September 25, 2012
posted by O Blitiri at 5:02 PM on September 25, 2012
Things like this envelop me in the most deliciously comforting feeling. My problems don't go away, but it's nice to share them with such vast infinitude of possibility.
Bad day at work? ULTRA DEEP FIELD.
Claustrophobic on your commute? ULTRA DEEP FIELD.
Need the knowledge that no matter what may befall you in your lifetime, to know that you are never, ever alone and are a welcomed and sought-after part of the entire enchilada?
ULTRA.
DEEP.
.....FIELD!
posted by Lipstick Thespian at 5:08 PM on September 25, 2012 [10 favorites]
Bad day at work? ULTRA DEEP FIELD.
Claustrophobic on your commute? ULTRA DEEP FIELD.
Need the knowledge that no matter what may befall you in your lifetime, to know that you are never, ever alone and are a welcomed and sought-after part of the entire enchilada?
ULTRA.
DEEP.
.....FIELD!
posted by Lipstick Thespian at 5:08 PM on September 25, 2012 [10 favorites]
scblackman, maybe this will help: Remember that you live in this universe. All those distant galaxies are in the same place as you. You are part of the same continuum as them. You are part of something huge!
posted by jiawen at 5:26 PM on September 25, 2012
posted by jiawen at 5:26 PM on September 25, 2012
If they have higher resolution images there's no reason for them not to release them.
Maybe in the higher resolution ones you can see the strings holding up the cardboard galaxies.
posted by bondcliff at 5:43 PM on September 25, 2012 [1 favorite]
Maybe in the higher resolution ones you can see the strings holding up the cardboard galaxies.
posted by bondcliff at 5:43 PM on September 25, 2012 [1 favorite]
Too bad the photos' resolutions are so crappy (even the 12MB TIFF). I guess that's all we mere peons can expect.
posted by Twang at 6:09 PM on September 25, 2012
posted by Twang at 6:09 PM on September 25, 2012
There are five thousand galaxies each with billions of stars in a patch of sky smaller than a grain of sand held out at arms length. This makes unloading the dishwasher tonight seem especially pointless.
posted by fzx101 at 7:23 PM on September 25, 2012 [6 favorites]
posted by fzx101 at 7:23 PM on September 25, 2012 [6 favorites]
So if there were nothing at all out there, it would make unloading the dishwasher more meaningful?
posted by weapons-grade pandemonium at 7:27 PM on September 25, 2012 [1 favorite]
posted by weapons-grade pandemonium at 7:27 PM on September 25, 2012 [1 favorite]
It seems that the public images aren't really that good -- the XDF, when I compare it back and forth with the largest image I can find of the Ultra Deep Field.... just doesn't seem to have all that many more visible objects.
There are more visible objects, to be sure, but with the publicly available images, I don't see a huge improvement.
You know, these are just PR photos. As in, there's a lot of good data that goes into these images and a lot of science that comes out of that data, but these pretty three-color images really have no utility other than being pretty to look at. And the process that goes into making these is entirely black-arts-ish, because you have a bunch of different exposures all with slightly different pointings, and you need to somehow put those onto a common scale and combine all of them together. Sometimes you register the data onto different pixel scale, because the actual instrument's pixels oversample the PSF of the telescope (smallest discernable feature is much bigger than a pixel), so you don't really loose much visually by doing that. Then there's an entirely separate issue of what do you do with the data from different filters, which by no means correspond to Red Green and Blue that we see, but somehow you have to map these filters onto these three colors.
Anyways, there are a variety of ways to do all of this, and it doesn't really matter which way they do it, because it's just for making pretty images and has nothing to do with the science. It's honestly much much harder to make pretty images than it is to extract useful science from the data. The angular resolution of the telescope is set (mostly) entirely by the size of the primary mirror (because it's in space, and because the instruments are designed to oversample the PSF), not by the pixel size of the instrument.
If they have higher resolution images there's no reason for them not to release them. And if there are no higher resolution images, it's not actually a deeper field than the UDF, just a longer exposure.
Just to be clear, "deeper" is not a super precise and defined term, but basically every astronomer anywhere understands "deeper" to mean "detecting fainter objects", which is something that you only get with exposure time, not angular resolution (anyone who would nit-pick me on this: yes I know the issue with seeing that you're thinking of, but that's tangential right now).
Secondly, most if not all of the data is public, so anyone can try to make a prettier version if they like. It's under a bunch of different proposals that you have to search for individually, but here's a list of some of the exposures that went into the image. It's all available in everyone's-favorite-image-format, FITS. But the data archive will also make little gif's for you to give you a taste of the data, here's one for example. I could spend days talking about all the awesome image artifacts in that one exposure.
tl,dr version: The pretty image you see was made from a bunch of exposures that look like this. And even if the PR images don't look that much different than before, the science we've gotten out of the new infrared data is absolutely amazing.
posted by kiltedtaco at 7:48 PM on September 25, 2012 [6 favorites]
There are more visible objects, to be sure, but with the publicly available images, I don't see a huge improvement.
You know, these are just PR photos. As in, there's a lot of good data that goes into these images and a lot of science that comes out of that data, but these pretty three-color images really have no utility other than being pretty to look at. And the process that goes into making these is entirely black-arts-ish, because you have a bunch of different exposures all with slightly different pointings, and you need to somehow put those onto a common scale and combine all of them together. Sometimes you register the data onto different pixel scale, because the actual instrument's pixels oversample the PSF of the telescope (smallest discernable feature is much bigger than a pixel), so you don't really loose much visually by doing that. Then there's an entirely separate issue of what do you do with the data from different filters, which by no means correspond to Red Green and Blue that we see, but somehow you have to map these filters onto these three colors.
Anyways, there are a variety of ways to do all of this, and it doesn't really matter which way they do it, because it's just for making pretty images and has nothing to do with the science. It's honestly much much harder to make pretty images than it is to extract useful science from the data. The angular resolution of the telescope is set (mostly) entirely by the size of the primary mirror (because it's in space, and because the instruments are designed to oversample the PSF), not by the pixel size of the instrument.
If they have higher resolution images there's no reason for them not to release them. And if there are no higher resolution images, it's not actually a deeper field than the UDF, just a longer exposure.
Just to be clear, "deeper" is not a super precise and defined term, but basically every astronomer anywhere understands "deeper" to mean "detecting fainter objects", which is something that you only get with exposure time, not angular resolution (anyone who would nit-pick me on this: yes I know the issue with seeing that you're thinking of, but that's tangential right now).
Secondly, most if not all of the data is public, so anyone can try to make a prettier version if they like. It's under a bunch of different proposals that you have to search for individually, but here's a list of some of the exposures that went into the image. It's all available in everyone's-favorite-image-format, FITS. But the data archive will also make little gif's for you to give you a taste of the data, here's one for example. I could spend days talking about all the awesome image artifacts in that one exposure.
tl,dr version: The pretty image you see was made from a bunch of exposures that look like this. And even if the PR images don't look that much different than before, the science we've gotten out of the new infrared data is absolutely amazing.
posted by kiltedtaco at 7:48 PM on September 25, 2012 [6 favorites]
I'm fine with them being "prettified". I know that they had to be enhanced to appeal to the layperson, and that's fine. It's not like there's fraud involved. And it's just so gorgeously mind-blowing that I spend way too much time just gazing on them in my desktop wallpaper with endless awe.
posted by The Sprout Queen at 7:58 PM on September 25, 2012
posted by The Sprout Queen at 7:58 PM on September 25, 2012
I know that the scientists and crew at STScI are working on raw/FITS images. Perhaps I wasn't clear, but my point was that there's still no reason that if the EPO people are directing someone to make images of the XDF for public consumption, to actually.... I dunno.... SHOW what's better about the XDF versus the UDF in the images.
There is much more data, many longer exposures of data in the XDF versus the UDF -- I never said I doubted that.
But it's pretty odd that the people who made the images for public consumption didn't bother to make a point of having them be visibly better than the previous generation to non-astronomers, is it not?
posted by chimaera at 9:16 PM on September 25, 2012
There is much more data, many longer exposures of data in the XDF versus the UDF -- I never said I doubted that.
But it's pretty odd that the people who made the images for public consumption didn't bother to make a point of having them be visibly better than the previous generation to non-astronomers, is it not?
posted by chimaera at 9:16 PM on September 25, 2012
DRINK MORE OVALTINE?!?
posted by roboton666 at 9:17 PM on September 25, 2012
posted by roboton666 at 9:17 PM on September 25, 2012
Are the galaxies in that A Flight Through the Universe video to scale? I'd always imagined that the distance between galaxies compared to the size of the galaxies would be comparable to the distance between stars compared to the size of solar systems, but here it looks like most galaxies are close to others, relatively speaking.
posted by ymgve at 9:27 PM on September 25, 2012
posted by ymgve at 9:27 PM on September 25, 2012
The galaxies always look prettier on the other side of the universe.
posted by mazola at 10:00 PM on September 25, 2012 [1 favorite]
posted by mazola at 10:00 PM on September 25, 2012 [1 favorite]
killedtaco, thanks for explaining a bit about what goes into producing the image. Maybe it's the data nerd in me but, for some reason, I found the noisy, raw, B&W image you linked to much more breathtaking.
posted by treepour at 10:28 PM on September 25, 2012
posted by treepour at 10:28 PM on September 25, 2012
This is just a guess, but the XDF PR image size is probably being driven by the fact that, unlike the UDF, they are making use of near-infrared images from the WFC3 camera, which has a poorer resolution than the optical ACS camera used for UDF. Each pixel of WFC3/IR corresponds to 0.13 arcseconds on the sky - 1 arcsecond is 1/3600 of a degree - while ACS pixels are 0.05 arcseconds across. Those pixel scales give about the right ratio of number of pixels for the two PR images.
Basically, each pixel of the XDF image corresponds to 1 pixel of WFC3/IR, but to about 2.5 pixels of the ACS data. The highest-detail Hubble images come from using the shortest-wavelength light (for which diffraction is a smaller effect than longer wavelengths); i.e., images from the telescope are blurred out to a degree which is proportional to wavelength. As a result, larger pixel sizes can be used for the IR detectors without loss of information.
The infrared images from Hubble are still extremely valuable despite being somewhat less sharp than those obtained in visible light. For instance, in many cases, stars in distant galaxies are almost entirely by vast clouds of dust, which longer-wavelength/redder light can penetrate more easily; many objects look radically different with WFC3 from ACS. Furthermore, the furthest galaxies, looking back to less than a billion years after the Big Bang, are completely invisible in optical images (as their shorter-wavelength light, which was emitted at ultraviolet wavelengths but redshifted into the optical by now) is all absorbed by hydrogen gas in the universe between them and us), but show up (barely) in the infrared. Unfortunately, the Earth's atmosphere is really bright in the infrared, so we can only find and study such objects efficiently from space.
posted by janewman at 11:14 PM on September 25, 2012 [3 favorites]
Basically, each pixel of the XDF image corresponds to 1 pixel of WFC3/IR, but to about 2.5 pixels of the ACS data. The highest-detail Hubble images come from using the shortest-wavelength light (for which diffraction is a smaller effect than longer wavelengths); i.e., images from the telescope are blurred out to a degree which is proportional to wavelength. As a result, larger pixel sizes can be used for the IR detectors without loss of information.
The infrared images from Hubble are still extremely valuable despite being somewhat less sharp than those obtained in visible light. For instance, in many cases, stars in distant galaxies are almost entirely by vast clouds of dust, which longer-wavelength/redder light can penetrate more easily; many objects look radically different with WFC3 from ACS. Furthermore, the furthest galaxies, looking back to less than a billion years after the Big Bang, are completely invisible in optical images (as their shorter-wavelength light, which was emitted at ultraviolet wavelengths but redshifted into the optical by now) is all absorbed by hydrogen gas in the universe between them and us), but show up (barely) in the infrared. Unfortunately, the Earth's atmosphere is really bright in the infrared, so we can only find and study such objects efficiently from space.
posted by janewman at 11:14 PM on September 25, 2012 [3 favorites]
"It's just PR... pretty, but practically useless".
Far be it from me to defend PR, but... you know we don't actually have to spend public money on deep space?
It would be lovely to imagine that the benefits of the great experiment of the Enlightenment were so profoundly obvious to all sentient beings that it would enjoy massive and passionate public support, but large chunks of the planet long droolingly for some imagined medieval world of kings, demons and passive serfs.
Apparently, medicine, electricity, universal literacy, universal suffrage and kitten videos aren't enough. Fuck knows why, but.
Pretty PR pictures ? Moar, plz.
posted by Devonian at 12:15 AM on September 26, 2012 [4 favorites]
Far be it from me to defend PR, but... you know we don't actually have to spend public money on deep space?
It would be lovely to imagine that the benefits of the great experiment of the Enlightenment were so profoundly obvious to all sentient beings that it would enjoy massive and passionate public support, but large chunks of the planet long droolingly for some imagined medieval world of kings, demons and passive serfs.
Apparently, medicine, electricity, universal literacy, universal suffrage and kitten videos aren't enough. Fuck knows why, but.
Pretty PR pictures ? Moar, plz.
posted by Devonian at 12:15 AM on September 26, 2012 [4 favorites]
I'd always imagined that the distance between galaxies compared to the size of the galaxies would be comparable to the distance between stars compared to the size of solar systems, but here it looks like most galaxies are close to others, relatively speaking.
Well, sort of. It's dealing with this stuff is kind of mindbending, but the big idea is you're not looking through SPACE, you're looking backwards in TIME. So, you're seeing the universe as it was in its first millions of years: "hotter", "smaller", and more "densely" populated. 13 billion years ago the galaxies would be a lot closer together than they are now.
posted by absalom at 6:46 AM on September 26, 2012
Well, sort of. It's dealing with this stuff is kind of mindbending, but the big idea is you're not looking through SPACE, you're looking backwards in TIME. So, you're seeing the universe as it was in its first millions of years: "hotter", "smaller", and more "densely" populated. 13 billion years ago the galaxies would be a lot closer together than they are now.
posted by absalom at 6:46 AM on September 26, 2012
Far be it from me to defend PR, but... you know we don't actually have to spend public money on deep space?
Totally. I know that pretty pictures is a topic I end up talking pretty glibly about, but I'm fully aware that giving the public a radically different perspective on the universe and our relation to it is the entire point of astronomy, and the HDF has done a better job of that than almost any other project I can think of. I should have tried to sound less dismissive of this point in my earlier comment.
posted by kiltedtaco at 6:50 AM on September 26, 2012 [1 favorite]
Totally. I know that pretty pictures is a topic I end up talking pretty glibly about, but I'm fully aware that giving the public a radically different perspective on the universe and our relation to it is the entire point of astronomy, and the HDF has done a better job of that than almost any other project I can think of. I should have tried to sound less dismissive of this point in my earlier comment.
posted by kiltedtaco at 6:50 AM on September 26, 2012 [1 favorite]
I'd always imagined that the distance between galaxies compared to the size of the galaxies would be comparable to the distance between stars compared to the size of solar systems, but here it looks like most galaxies are close to others, relatively speaking.
Well that's a fun thought. So let's guess a distance between stars, 1 parsec is pretty good, and say a planetary system is about 50 AU in radius (very roughly). That's a factor of 4000 difference. A typical decent sized galaxy is about 10 kpc in radius, so for the scaling to hold, the nearest (decent sized) galaxy would have to be 40 Mpc away, which is indeed a little high. Andromeda is only ~750 kpc away, and there are plenty of galaxies within say 5 Mpc. So yeah, I think you're correct on that.
Although I would think of it as planetary systems are just really really small.
posted by kiltedtaco at 7:02 AM on September 26, 2012
Well that's a fun thought. So let's guess a distance between stars, 1 parsec is pretty good, and say a planetary system is about 50 AU in radius (very roughly). That's a factor of 4000 difference. A typical decent sized galaxy is about 10 kpc in radius, so for the scaling to hold, the nearest (decent sized) galaxy would have to be 40 Mpc away, which is indeed a little high. Andromeda is only ~750 kpc away, and there are plenty of galaxies within say 5 Mpc. So yeah, I think you're correct on that.
Although I would think of it as planetary systems are just really really small.
posted by kiltedtaco at 7:02 AM on September 26, 2012
I'm going to wait for Ludicrously Deep Field before I upgrade.
posted by Kabanos at 8:38 AM on September 26, 2012 [1 favorite]
posted by Kabanos at 8:38 AM on September 26, 2012 [1 favorite]
Metafilter: Kitten videos are not enough.
posted by Lipstick Thespian at 8:41 AM on September 26, 2012 [1 favorite]
posted by Lipstick Thespian at 8:41 AM on September 26, 2012 [1 favorite]
That flight through the universe video that Think_Long linked to is nonsense, right? Because some of the starlight we see is much older than others, even if it looks like the stars are right next to each other from our angle.
So whether you flew out there at lightspeed, or you magically teleported out there right "now" (whatever that means) or you could time-travel and go back to the time and place the starlight began, you wouldn't see what's in that video. Because the stars were never actually in a configuration that is the same as they appear to us now with all their light arriving at different times, right?
That's what always bugged me about programs like Celestia. It simulates the star positions as seen from Earth, and you can watch them move by accelerating time forwards and back, and you can also move your point of view out to any of those stars. But the extrapolated view from a star 10,000 light years away is not actually something that you ever would have seen if you were really there.
posted by straight at 9:24 AM on September 26, 2012
So whether you flew out there at lightspeed, or you magically teleported out there right "now" (whatever that means) or you could time-travel and go back to the time and place the starlight began, you wouldn't see what's in that video. Because the stars were never actually in a configuration that is the same as they appear to us now with all their light arriving at different times, right?
That's what always bugged me about programs like Celestia. It simulates the star positions as seen from Earth, and you can watch them move by accelerating time forwards and back, and you can also move your point of view out to any of those stars. But the extrapolated view from a star 10,000 light years away is not actually something that you ever would have seen if you were really there.
posted by straight at 9:24 AM on September 26, 2012
straight: So whether you flew out there at lightspeed, or you magically teleported out there right "now" (whatever that means) or you could time-travel and go back to the time and place the starlight began, you wouldn't see what's in that video. Because the stars were never actually in a configuration that is the same as they appear to us now with all their light arriving at different times, right?
You can log when or you can log where. Gotta pick one. Please, can you graph this?
I look at the night sky--those myriad thens, all arriving at my eyeball at the same time--I am willingly stunned. What I see that never was, was coordinated into a fictional now by the power of rationalization (and coincidental lightspeed): I am the center of the universe. This charming affectation contains the seeds of magic, being true and false at the same time.
No. When you fly toward the distant stars at hyperlightspeed, you watch them age before your eyes, and when you fly away, you watch them grow younger. The topography escapes me, perhaps because I don't have an adequately deveoped topograph.
Never mind. I retreat back into my new wallpaper.
posted by mule98J at 2:21 PM on September 26, 2012 [2 favorites]
You can log when or you can log where. Gotta pick one. Please, can you graph this?
I look at the night sky--those myriad thens, all arriving at my eyeball at the same time--I am willingly stunned. What I see that never was, was coordinated into a fictional now by the power of rationalization (and coincidental lightspeed): I am the center of the universe. This charming affectation contains the seeds of magic, being true and false at the same time.
No. When you fly toward the distant stars at hyperlightspeed, you watch them age before your eyes, and when you fly away, you watch them grow younger. The topography escapes me, perhaps because I don't have an adequately deveoped topograph.
Never mind. I retreat back into my new wallpaper.
posted by mule98J at 2:21 PM on September 26, 2012 [2 favorites]
Things like this envelop me in the most deliciously comforting feeling.
Well said. It's partly the initial shock of strangeness quickly overtaken by an odd familiarity. It seems like it has to be this way and it's wonderful that it is...
posted by Mental Wimp at 4:51 PM on September 26, 2012
Well said. It's partly the initial shock of strangeness quickly overtaken by an odd familiarity. It seems like it has to be this way and it's wonderful that it is...
posted by Mental Wimp at 4:51 PM on September 26, 2012
chimaera writes ""But it's pretty odd that the people who made the images for public consumption didn't bother to make a point of having them be visibly better than the previous generation to non-astronomers, is it not?"
Maybe, if the images weren't of two different things. The poor image is a tiny fraction of the original but shows, give or take, the same number of objects. That's pretty amazing. It's like viewing single celled organisms in a microscope and then zooming in until you could see the viruses that infect those cells (I've probably got the order of magnitude wrong here; I'm not even an internet biologist). That the much smaller objects aren't as clear is to be expected.
posted by Mitheral at 6:20 PM on September 26, 2012
Maybe, if the images weren't of two different things. The poor image is a tiny fraction of the original but shows, give or take, the same number of objects. That's pretty amazing. It's like viewing single celled organisms in a microscope and then zooming in until you could see the viruses that infect those cells (I've probably got the order of magnitude wrong here; I'm not even an internet biologist). That the much smaller objects aren't as clear is to be expected.
posted by Mitheral at 6:20 PM on September 26, 2012
it's pretty odd that the people who made the images for public consumption didn't bother to make a point of having them be visibly better than the previous generation to non-astronomers, is it not?
On the contrary. In popular culture, a blurry science photo is shorthand for "We said ENHANCE! 95 times and the zoom level is so crazy extreme we had to capitalize the 'x" in eXtreme!"
posted by straight at 7:06 PM on September 26, 2012
On the contrary. In popular culture, a blurry science photo is shorthand for "We said ENHANCE! 95 times and the zoom level is so crazy extreme we had to capitalize the 'x" in eXtreme!"
posted by straight at 7:06 PM on September 26, 2012
I don't know why people are saying the XDF is of "a small region" of the UDF; it covers more than half the area of the UDF. I started with the links chimaera posted and crudely superimposed them in photoshop ... (files are ~5MB ea)
UDF with outline of XDF
UDF with XDF superimposed
If you flip between the two images, you can see that there are red objects in the XDF that don't show on the UDF. But it isn't of a much smaller patch of sky.
posted by nickp at 9:13 PM on September 27, 2012
UDF with outline of XDF
UDF with XDF superimposed
If you flip between the two images, you can see that there are red objects in the XDF that don't show on the UDF. But it isn't of a much smaller patch of sky.
posted by nickp at 9:13 PM on September 27, 2012
Contrary to the way the deep red objects work, there's at least one object on the UDF that vanishes in the XDF ... almost in the center of the UDF, there is what appears to be an elliptical galaxy that doesn't show on the XDF. Hmmm.
posted by nickp at 9:47 PM on September 27, 2012
posted by nickp at 9:47 PM on September 27, 2012
nickp writes "I don't know why people are saying the XDF is of 'a small region' of the UDF; it covers more than half the area of the UDF."
As one of those people I, uh, have no idea. Some how I thought the XDF was like a 10th of the size of the UDF.
Still half the area at the same image size means half the information and twice the fuzziness (or is is 4X; that trips me up all the time).
posted by Mitheral at 10:18 PM on September 27, 2012
As one of those people I, uh, have no idea. Some how I thought the XDF was like a 10th of the size of the UDF.
Still half the area at the same image size means half the information and twice the fuzziness (or is is 4X; that trips me up all the time).
posted by Mitheral at 10:18 PM on September 27, 2012
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