To grasp a billion stars

By Phil Plait | April 4, 2012 6:00 am

There are times — rare, but they happen — when I have a difficult time describing the enormity of something. Something so big, so overwhelming, that words simply cannot suffice.

The basic story is: Using the VISTA telescope in Chile and the UKIRT telescope in Hawaii, astronomers have made an incredibly detailed map of the sky in infrared. This map will help understand our own galaxy, more distant galaxies, quasars, nebulae, and much more.

But what do I mean by "incredibly detailed"?

This is where words get hard. So hang on tight; let me show you instead.

Here’s a section of the survey they made, showing the star-forming region G305, an enormous cloud of gas about 12,000 light years away which is busily birthing tens of thousands of stars:

[Click to enstellarnate.]

Pretty, isn’t it? There are about 10,000 stars in this image, and you can see the gas and dust that’s forming new stars even as you look.

But it’s the scale of this image that’s so amazing. It’s only a tiny, tiny part of this new survey. How tiny? Well, it came from this image (the area of the first image is outlined in the white square):

Again, click to embiggen — it’ll blow your socks off. But we’re not done! That image is a subsection of this one:

… which itself is a subsection of this image:

Sure, I’ll admit that last one doesn’t look like much, squished down into a width of a few hundred pixels here for the blog. So go ahead, click on it. I dare you. If you do, you’ll get a roughly 20,000 x 2000 pixel picture of the sky, a mosaic made from thousands of individual images… and even that is grossly reduced from the original survey.

How big is the raw data from the survey? Why, it only has 150 billion pixels aiieeee aiieeeeee AIIEEEEE!!!

And this would be where I find myself lacking in adjectives. Titanic? Massive? Ginormous? These all fail utterly when trying to describe a one hundred fifty thousand megapixel picture of the sky.


And again, why worry over words when I can show you? The astronomers involved helpfully made the original data — all 150 billion pixels of it — into a pan-and-zoomable image where you can zoom in, and in, and in. It’s hypnotizing, like watching "Inception", but made of stars.

And made of stars it is: there are over a billion stars in the original image! A billion. With a B. It’s one of the most comprehensive surveys of the sky ever made, and yet it still only scratches the surface. This survey only covers the part of the sky where the Milky Way galaxy itself is thickest — in the bottom image above you can see the edge-on disk of our galaxy plainly stretching across the entire shot — and that’s only a fraction of the entire sky.

Think on this: there are a billion stars in that image alone, but that’s less than 1% of the total number of stars in our galaxy! As deep and broad as this amazing picture is, it’s a tiny slice of our local Universe.

And once again, we’ve reached the point where I’m out of words. Our puny brains, evolved to count the number of our fingers and toes, to grasp only what’s within reach, to picture only what we can immediately see — balk at these images.

But… we took them. Human beings looked up and wondered, looked around and observed, looked out and discovered. In our quest to seek ever more knowledge, we built the tools needed to make these pictures: the telescopes, the detectors, the computers. And all along, the power behind that magnificent work was our squishy pink brains.

A billion stars in one shot, thanks to a fleshy mass of collected neurons weighing a kilogram or so. The Universe is amazing, but so are we.

Images credit: Mike Read (WFAU), UKIDSS/GPS and VVV

Related Posts:

Tour the galaxy with this pan-and-scan all-sky picture!
What does a half million galaxies look like?
An ultradeep image that’s *full* of galaxies!
Adler planetarium unleashes 2.5 gigapixel image of the galaxy
The new VLT Survey Telescope delivers spectacular images

MORE ABOUT: Milky Way, stars, UKIRT, VISTA

Comments (80)

  1. brett

    hmmmmm …… space is BIG

  2. Mikey

    Funny – your post came along just as this came on the radio.

    Dig it baby – space is big. And groovy.

  3. Jonathan Strickland

    My God, it’s full of stars!

  4. the return

    seems like there isn’t enough space for all those stars

  5. runawayuniverse

    Gonna count the stars … brb

  6. errol6942

    Douglas Adams had it right in HHGTTG when he wrote:

    Space is big. You just won’t believe how vastly, hugely, mind- bogglingly big it is. I mean, you may think it’s a long way down the road to the chemist’s [drugstore/pharmacy], but that’s just peanuts to space.

  7. Jabjabs

    Well I have a new source image to build a new desktop image for my PC 😀

  8. harry

    “The solar system is off center and consequently man is too.” ~ Howard Shapley

  9. Joseph

    “Iz fulla starz…!”

  10. @Jabjabs,

    Someone should write a program that would randomly splice off desktop-sized chunks of the main image. This way, every time you loaded your PC, you could have a completely different starry background. (I’m thinking that working with a 20,000 x 2,000 pixel image like this would take some processing power though.)

  11. Whenever one of these giant images is released, I like to envision printing them out on a poster. This poster would be one foot tall, but over 11 feet long! (That’s at 150 pixels per inch.)

  12. Jones The Code

    Absolutely mind-boggling! I have a question: “you can see the edge-on disk of our galaxy plainly stretching across the entire shot — and that’s only a fraction of the entire sky” – what size fraction is that (roughly)?

  13. There goes the rest of my day. Playing with that pan and zoom image could take me all the way through to the weekend!

  14. David

    …and this was created in how many days? ….

  15. Hi Phil thanks for posting this. It puts a tiny dent in the difficulty of grasping the enormity of space. That this is just but one galaxy in a uinverse of billions increases the wonder factor to the power of ∞

    So beautiful visiually and intellectually. Not enough superlatives to encompass it.

    Would be great, and perhaps this is something being worked on, if the catalogued stars were indexed so that a mouseover indicates what they are etc. or if you could do a search for a specific star, Rigel, for example.

    Thank you for lifting me out of the “antiproductivity pod” bureaucratic wasteland I work in this morning.

  16. Alright, call me hyper hard to please… *yawn*…. I’d be more impressed if this had been a STEREO image, say with a second shot from somewhere around Beta-Zed. This one has no depth, kinda like the Republican candidates (another *yawn*).

  17. Nick

    Notice the black bars covering a lot of the areas up?

    Those are where the extra-terrestrial civilizations are. The government just doesn’t want us to know about them. But I know. Oh I know.

  18. reidh

    How do you know that “new” stars are coming to be out of the clouds of gas around them? Can you point out a set of videos or time lapse photos or whatever that show that that is what is happening ? I have never actually seen the birth of any star, only heard tell of it from the likes of you. How do you know that the stars aren’t being swallowed up by the surrounding gas. Its all very hypothetical and just wishing it were the way you say it are doesn’t make it so.

  19. Bad Wolf

    The big question, though, is what is in those blacked-out sections. What are the “scientists” not telling us???

    It’s a conspiracy, I tell you, they are hiding clear-cut EVIDENCE of Nibiru, and the rest of the 2012 prophecies!!!1!!

  20. Brain melty awesomeness.
    This is another photo that should be uploaded as a torrent so we can all download it. Though, I would probably just look at it for days and get nothing done.

  21. Wzrd1

    Oh, crud! I just found the Vogon construction fleet in the large image and they’re massively blue shifted.

  22. Nigel Depledge

    Reidh (13) said:

    How do you know that “new” stars are coming to be out of the clouds of gas around them? Can you point out a set of videos or time lapse photos or whatever that show that that is what is happening ? I have never actually seen the birth of any star, only heard tell of it from the likes of you. How do you know that the stars aren’t being swallowed up by the surrounding gas. Its all very hypothetical and just wishing it were the way you say it are doesn’t make it so.

    Time lapse would need unfeasibly long timescales (say, thousands of years between snapshots) to view the process in a human time frame.

    But this does not mean that astronomers don’t know a newly-formed star when they see it. The disposition of dust and gas, that indicate extreme stellar winds, the absence of fluorescing gas such as is thrown off by a red giant near the end of its life, the spectral signatures of the various components of those systems – all of these things indicate clearly whether a star is young, middle-aged or old.

    This understanding has been assembled over the course of a couple of centuries or so, and I’m sure there are plenty of popular-science books that describe the development of the field of astronomy if you care to take a look.

  23. Jebediah Kerman

    Fascinating! But one stupid question: I don´t see any galaxies in the image. Why?

  24. I feel this is obligatory:

    Whenever life gets you down, Mrs. Brown,
    And things seem hard or tough,
    And people are stupid, obnoxious or daft,

    And you feel that you’ve had quite eno-o-o-o-o-ough,

    Just remember that you’re standing on a planet that’s evolving
    And revolving at 900 miles an hour.
    It’s orbiting at 19 miles a second, so it’s reckoned,
    The sun that is the source of all our power.
    Now the sun, and you and me, and all the stars that we can see,
    Are moving at a million miles a day,
    In the outer spiral arm, at 40,000 miles an hour,
    Of a galaxy we call the Milky Way.

    Our galaxy itself contains a hundred billion stars;
    It’s a hundred thousand light-years side to side;
    It bulges in the middle sixteen thousand light-years thick,
    But out by us it’s just three thousand light-years wide.
    We’re thirty thousand light-years from Galactic Central Point,
    We go ’round every two hundred million years;
    And our galaxy itself is one of millions of billions
    In this amazing and expanding universe.

    Our universe itself keeps on expanding and expanding,
    In all of the directions it can whiz;
    As fast as it can go, at the speed of light, you know,
    Twelve million miles a minute and that’s the fastest speed there is.
    So remember, when you’re feeling very small and insecure,
    How amazingly unlikely is your birth;
    And pray that there’s intelligent life somewhere out in space,
    ‘Cause there’s bugger all down here on Earth!

  25. VinceRN

    This picture of space is big. You just won’t believe how vastly, hugely, mind- bogglingly big it is…

  26. Novo


    You can tell stars are coming out of the gas clouds instead of being swallowed by them quite easily by analyzing the spectrum shift of the light produced by both the star and the surrounding clouds to determine which is moving in what direction, furthermore the magnitude and intensity of the light will tell you the makeup of each and at what state the stars are in their lifecycle.

    None of it is hypothetical this is all very real and testable.

    Thanks for your skepticism, without it, we can’t test our knowledge! :)

  27. Malle

    When looking closely at the image I notice that many stars have a small dark or black dot in the middle. Why is this? I suspect it’s some form of artifact from the survey. If so, why do such artifacts appear?

  28. Congratulations to VISTA & UKIRT for the amazing data! Though I would like to point out that SDSS-III released over a trillion pixels in January of 2011, so they still have a way to go. :)

  29. BaronGrim

    I’ve been describing this image as a tiny, miniscule sample of what it would be like to be put into The Total Perspective Vortex, the torture device that Douglas Adams wrote about.

    **When you are put into the Vortex you are given just one momentary glimpse of the entire unimaginable infinity of creation, and somewhere in it a tiny little mark, a microscopic dot on a microscopic dot, which says, “You are here.”**

    It destroys your brain because, as he eloquently said, “In an infinite universe, the one thing sentient life cannot afford to have is a sense of proportion.”

  30. James

    There’s a big green spot with a black dot in the middle of it kind of in the centre of the image and down a bit. Is that a black hole?

  31. michaelg

    150 Billion pixels. Figure 4 bytes per pixel to capture all the color information so you have 600 Billion bytes or 6×10^11 bytes of data. Those bytes weren’t captured all in one day but are a survey’s compilation.

    Now think. The square kilometer radio array that’s proposed for South Africa will capture 10^18 bytes, every day. That’s 10 million times more information every single day the array operates. They’re hoping that by the time the array is up and running, computers have advanced enough just to handle the load. They don’t think storage technology will advance quickly enough so they’re planning on throwing away 1000 bytes for every one they keep.

  32. Chance

    Are the large stars with black dots inside them signs of transiting planets?!?!?! There’s so many of them like that!

  33. Cindy


    I tried clicking on the pan and zoom and I think we’ve taken the server down.

    Now I know what to show (besides a galaxy) when I want to show the concept of a billion.

  34. Now that is a really cool picture. Its amazing how large the universe is. And we haven’t even scratched the surface.

  35. Milo Balls

    “Embiggens? I never heard that word before I moved to Springfield.”
    “I don’t know why. It’s a perfectly cromulent word.”

  36. Chris A.

    “And this would be where I find myself lacking in adjectives. Titanic? Massive? Ginormous?”

    But Phil, surely the adjective you are groping for here is “astronomical,” n’est-ce pas?

  37. Rajesh

    @Jebediah Kerman:

    You don’t see any galaxies in the picture, because the picture is just a small portion of our own galaxy.

  38. Jeff Phinney

    And there are a lot of comments here. Many, many, many comments.

  39. Jordan

    As the saying goes, “A picture is worth a thousand words”. Or in this case, over a Billion!!!

    No worries Phil, that should cover it!

    Or, just for fun, what about ‘supercalifragilisticexpialidocious’ ?!?! I had to look up the meaning before suggesting it, and I think it actually… kinda… applies.

  40. Thanks, Phil!
    Just in time for our “Website of the month” feature for toninght’s CAS meeting at McCormick Observatory! If any of you BAblogees are in Charlottesville, come on up! Chris Irwin will be talking about supernovae!

  41. The original source is 150 billion pixels. The complete image Phil links to is 20,000 x 2,000. This means a ratio of 10 to 1. If the original height is x, then the width of the original source would be 10x. Or:

    x * 10x = 150,000,000,000

    This means source image would be about 122,474 pixels tall and about 1,224,745 pixels tall. If you were to print this at 150 dpi, you’d get a poster 68 feet tall and 680 feet long.

    For comparison, a football field is 160 feet wide and 360 feet long (including end zones). This poster would cover 80% of the football field’s square footage. (If my math is right here.)

  42. Fantastic, I want to print it out and hang it on the side of a building. 😀

  43. Dunno

    What are the black dots at the center of white stars? Are those mechanical things in the telescope that limit the direct light output from those objects so as to avoid obscuring nearby objects?

  44. Russell

    How did the universe get sooooo big!?!

  45. Kendall

    It’s surprising to see how dirty it is. Lots of dust! That’s even more interesting than the stars. Probably will create more than 150 billion stars.

  46. machtyn

    A pink squishy brain with firing neurons… and a soul and intelligence. (Hey, did an inkshop explode somewhere and create a dictionary?)

    These images are quite impressive. Space truly is mindblowingly big.

  47. dj

    I see all the black squares and immediately think there’s something there we aren’t supposed to know about.

  48. Crux Australis

    “My god…it’s full of…” oh never mind.

  49. is0butane

    Now think of this… the US national debt is almost 15, yes 15 Trillion dollars. Let that sink in…

  50. Clicking and loading that 20,000x2000pixel image felt like loading porn back in 1998. So few lines per second. Such a great payoff ^^;

  51. Per

    Hardest “Where is Wally” yet.

  52. James

    We are amazing? Yes we are legends in our own minds. Yes we can do this and yet cant even get back to the moon which is only 250000 miles away. Pathetic really.

  53. Brazen Normalcy

    Too bad it doesn’t have a co-ordinate system. Then, Phil, when you showed us something outside our solar system but inside our galaxy, you could tell us where to go see it in a larger context.

  54. HvP

    As Chris A. said, indeed the adjective “astronomical” exists for this very subject!

  55. Brian Too

    “All these worlds are yours, except Europa…”

    OK OK, you can have Europa!

  56. #44, “Dunno”:
    The black dots are an artifact of the image processing software. You have my permission to ignore them henceforth.

  57. Jebediah Kerman

    @rajesh Yes shure. But at the edges of the image one should see at least a few galaxies shining through. Nevermind.

  58. mfumbesi

    “The Universe is amazing, but so are we.” This line is just begging to be quoted on my BAUT sig.

  59. Nigel Depledge

    @ Jebediah Kerman (61) –
    Exposure time.

    Distant galaxies are faint. Stars that are (relatively) nearby are significantly brighter. If the images had been exposed to show galaxies, we’d see galaxies, but the area around each nearby star would be burnt out in the image from the light overload.

    Note that deep-field images are only taken of sections of sky that don’t have any nearby stars in them.

  60. Nick Cross

    As well as the surveys of the Galactic Plane which were shown in the image, both VISTA and UKIRT have been doing several other surveys. There are several extragalactic surveys in each case: one wide (in the case of VISTA, the whole hemisphere) and then deeper narrower ones in a wedding cake arrangement. VISTA is also doing a survey of the Magellanic Clouds and UKIRT one of Galactic Clusters like the Pleiades.
    Along with the billion star image we are releasing a lot of the first year of VISTA data to the public through the VISTA Science Archive The black rectangles are where data hasn’t been taken yet or the data wasn’t good enough quality in one of the filters used in the colour image.
    Since the image is of the Galactic Plane and Bulge, most distant galaxies are lost in the dust or stars of our own galaxy, but there are one or two that can be found in the image.

  61. #17 reidh:
    As per the subject of this post, there are a huge number of stars in the Galaxy. It’s also very old, and stars of different masses have different lifetimes. There are also several generations of stars; many of the oldest have long since died, and newer ones have formed since.
    Put all these facts together, and we can see stars at every possible stage of their life cycles. While we obviously can’t actually observe any individual star going through its life, we can observe a great many stars at all the different stages of their lifecycles, and therefore deduce the sequence of events.
    So you come to an astronomy blog, and try to ridicule some of the most fundamental concepts on which astronomy and astrophysics are founded. But then, you do that for every other branch of science as well, don’t you? Why exactly do you bother coming here???

  62. bela okmyx

    “There are times — rare, but they happen — when I have a difficult time describing the enormity of something. Something so big, so overwhelming, that words simply cannot suffice.”

    The word you’re looking for, Phil, is “enormousness”; “enormity” means of outrageous or heinous character or atrociousness. It’s a common mistake because the words sound similar, but they have entirely different meanings.

  63. Xavier Francisco

    Interactive map of the image above.

    Edit:Forget it 😛 Didn’t see the link in your post, sorry 😉

  64. Kathy King

    Insignificant … that’s how I’m feeling right now … speechless … awestruck. Thank you for putting things in perspective for me today!

  65. Anon 34

    …And yet bronze-age raticals still think we’re the center of the univere that was created just for us and we’re the only intelegent life forms.

    Can you spell STUPID?!?

  66. Si

    what are the black patches, i see things like this and it makes me paranoid there are things close that we arn’t authorised to lay eyes on…

  67. Wow a page of comments that doesn’t blame something on that Marxist Obama.

  68. Matt B.

    WOOHOO, less than a month behind!

  69. X-101

    Article describing how image was created, processed and put online:


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