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The Deepest Photo Ever Taken

Astroturtle writes "Astronomers using the Hubble Space Telescope's powerful new Advanced Camera for Surveys (ACS) have taken the deepest visible-light image ever made of the sky. The 3.5-day (84-hour) exposure captures stars as faint as 31st magnitude, according to Tom M. Brown (Space Telescope Science Institute), who headed the eight-person team that took the picture."

218 comments

  1. Comment removed by account_deleted · · Score: 3, Funny

    Comment removed based on user account deletion

  2. article by CowBovNeal · · Score: 3, Informative

    May 7, 2003 | Astronomers using the Hubble Space Telescope's powerful new Advanced Camera for Surveys (ACS) have taken the deepest visible-light image ever made of the sky.

    The 3.5-day (84-hour) exposure captures stars as faint as 31st magnitude, according to Tom M. Brown (Space Telescope Science Institute), who headed the eight-person team that took the picture. This is a little more than 1 magnitude (2.5 times) fainter than the epochal Hubble Deep Fields, which were made with the Hubble's Wide Field and Planetary Camera 2. It is 6 billion times fainter than what can be seen with the naked eye.

    Brown and his colleagues chose to point at a spot 1 southeast of M31, the Great Andromeda Galaxy, in order to get a census of faint stars populating M31's outer halo. The full ACS image is about 3.1 arcminutes square, the size of a sand grain held at arm's length against the sky. The ACS magnifies this small field into a vast panorama of some 300,000 stars and thousands of faint background galaxies. At M31's distance of 2.5 million light-years, the faintest of the stars are slightly less luminous than our Sun. A large fraction of the most distant galaxies appear patchy and irregular, testimony to the collisions and mergers in the early universe that built up the familiar galaxies we see closer around us today.

    Most of the stars in the image indeed proved to be in M31's halo, judging from their colors and brightnesses. Moreover, they show a surprisingly wide range of estimated ages -- from 6 to 13 billion years, compared to 11 to 13 billion years for our Milky Way's halo stars. Perhaps M31 has captured and torn apart younger dwarf galaxies than our Milky Way has done. Or perhaps M31 underwent a massive, disruptive merger with a single large galaxy billions of years ago; in this scenario some of M31's younger disk stars could have been flung into its halo. Or maybe some combination of these events triggered waves of star formation in regions that ended up in M31's outer fringes.

    The image was made in two colors: near-infrared and "visual" (a band spanning the part of the spectrum running from yellow through green). The renditions displayed here were crafted to resemble true-color views by interpolating from these two colors. These vignettes each show only about 1 percent of the ACS image. The full image is available from the Hubble Telescope's press site at various qualities and sizes (up to 128 megabytes), along with more highlights and a finder chart showing its relation to M31.

    Plans are afoot for an even deeper "Ultra-Deep Field," which will use ACS for longer exposures in four colors and go slightly fainter still.

    --
    Bush is on fire and its not good for my lungs.
    1. Re:article by Anonymous Coward · · Score: 0

      Who are you? The nanny of Slashdot? Methinks you need to get a hobby, son.

      The only thing lower than a troll...is a troll buster.

    2. Re:article by Anonymous Coward · · Score: 0

      >The only thing lower than a troll...is a troll buster.

      Naah, surely trolls are lower? Because some troll-busters perform a useful function (pointing out goatse links, for instance) whereas by definition trolls never do.

    3. Re:article by Anonymous Coward · · Score: 0

      And methinks you can bend over and suck my dick. You're probably just trying to protect the karma points you're trying to collect up.

    4. Re:article by Anonymous Coward · · Score: 0

      No, I'm afraid you're both annoying as fuck.

  3. Re:This is the first? Can't be! by DrDaman · · Score: 0, Offtopic

    2nd, we hope

    --
    Mess with the best. Die like the rest!
  4. How? by r84x · · Score: 0, Flamebait

    How did they take this over 3.5 days? Didn't the sun get in the way? Last time I checked, only regions north of the arctic circle get no light for a few days, and that only occurs at specific times of year, so... what gives?

    --
    Karma: Can there be a void?

    .. -. - . .-. .-. --- -...

    1. Re:How? by Biogenesis · · Score: 1

      The photo was taken by hubble, it's in orbit around Earth.

    2. Re:How? by r84x · · Score: 1, Insightful

      Ah, yes, my bad, that will teach me to read an article that fast. My apologies to all who had to see my stupid question.

      --
      Karma: Can there be a void?

      .. -. - . .-. .-. --- -...

    3. Re:How? by Anonymous Coward · · Score: 0

      ...idiot

  5. 3.5 Day Exposure? by Anonymous+Canard · · Score: 5, Interesting

    Imagine a Beowulf... um. Seriously, how do you cope with reciprocity failure in a 3.5 day exposure. I would have thought that stray heat or electron flow would turn the whole image to static with such a long exposure. HST must consist of unfathomably cool (literally and figuratively) electronics.

    --

    --
    BitTorrent in C -- LibBT
    http://www.sf.net/projects/libbt
    1. Re:3.5 Day Exposure? by Biogenesis · · Score: 5, Insightful

      ...and it is, hubble has some type of cryogenic cooler onboard. At least according to an article in Sky and Space magazine (it's an australian one AFAIK) a while back that talked about all the extra stuff that was put on hubble last time a shuttle stopped by to maintain it.

    2. Re:3.5 Day Exposure? by roseblood · · Score: 1

      And, to think I used to complain about having to get the tripod out for exposures that were longer than 1/8th of a second! I'll never comlpain about slow film or lenses again!

      --
      There are lies, damned lies, and statistics.
    3. Re:3.5 Day Exposure? by deathcow · · Score: 5, Informative

      Astrophotos are commonly made by combining many shorter exposures. Each additional exposure improves the signal to noise ratio yielding progressively greater detail.

      As far as color and reciprocity, Hubble color shots are not always as the eye sees them. The famous "pillars of creation" shot for example, presented the light from oxygen ionization in one color, the light from sulfur ionization in another color, the light from hydogren ionization in another color.

    4. Re:3.5 Day Exposure? by Liquid+Tip · · Score: 5, Informative

      CCDs do not suffer from Reciprocity failure like film does. However there are other problems that will turn long exposures into junk (such as cosmic rays as HST is not sheltered by the earths atmosphere!). So many shorter exposures are taken and then coadded to make a 3.5 day exposure.

    5. Re:3.5 Day Exposure? by kanajlo · · Score: 1

      Poetic license.

    6. Re:3.5 Day Exposure? by Anonymous Coward · · Score: 0

      >HST must consist of unfathomably cool (literally
      >and figuratively) electronics.

      Do you really mean `literally cool`?

    7. Re:3.5 Day Exposure? by Anonymous+Canard · · Score: 1
      >HST must consist of unfathomably cool (literally
      >and figuratively) electronics.

      Do you really mean `literally cool`?

      The only thing worse than a grammar pedant is a grammar pedant who doesn't read the article he is criticizing. Since uneven heat flow would lead to spurious readings from a normal CCD; yes, I did 'really' mean 'literally cool'.

      --

      --
      BitTorrent in C -- LibBT
      http://www.sf.net/projects/libbt
    8. Re:3.5 Day Exposure? by adminispheroid · · Score: 1

      The cooler is for NICMOS. This picture was taken with ACS, a different instrument.

  6. "Deep" Photo by Landaras · · Score: 0, Offtopic

    Regarding "deep" photos, might a goatse link actually be on topic for once?

    No, I'm not going to provide it...

    1. Re:"Deep" Photo by shamilton · · Score: 1, Redundant

      They took it from space.

      What I find fascinating is that they were able to keep the telescope still for that long. With a field of view that low, even microscopic rotations could ruin the shot.

      --
      "[A] high IQ is like a Jeep; you will still get stuck, just farther from help!" --Just d' FAQs, c.g.a
    2. Re:"Deep" Photo by Anonymous Coward · · Score: 0

      I beat you =P

    3. Re:"Deep" Photo by Anonymous Coward · · Score: 0

      you dont need to provide it. Your a living proof of it.

    4. Re:"Deep" Photo by Landaras · · Score: 0

      I'm fully aware that they took it from space.

      I was trying to be humorous :).

    5. Re:"Deep" Photo by shamilton · · Score: 1

      Whoops, I replied to the wrong post. First time for me.

      --
      "[A] high IQ is like a Jeep; you will still get stuck, just farther from help!" --Just d' FAQs, c.g.a
    6. Re:"Deep" Photo by Anonymous Coward · · Score: 0

      offtopic? For once this is actually on topic.

    7. Re:"Deep" Photo by Anonymous Coward · · Score: 0

      How deep can it go? Can it see into ur-anus?

    8. Re:"Deep" Photo by Unkle+Ka5 · · Score: 0, Offtopic

      As always the BOTTOM line is an ASSHOLE joke :)

  7. Commence with the porn jokes! by Overly+Critical+Guy · · Score: 0, Redundant

    Let's do a preemptive strike and declare all the impending idiotic Slashbot porn jokes to be ineffective, unclever, and the most obvious route to take.

    You're not funny! Don't do it; hold yourself back!

    --
    "Sufferin' succotash."
    1. Re:Commence with the porn jokes! by PS-SCUD · · Score: 0, Offtopic

      "Don't do it; hold yourself back!" But it's so HARD to.

      --


      "Much work is lost, for the lack of a little more." -Edward H. Harriman
    2. Re:Commence with the porn jokes! by Anonymous Coward · · Score: 0

      well said, please try and hold the goatse jokes down to a minimum

    3. Re:Commence with the porn jokes! by Anonymous Coward · · Score: 0

      i do NOT want to know what your holding onto.

  8. It would be interesting to know... by HotNeedleOfInquiry · · Score: 3, Interesting

    Just how many photons they detected for the faintest star.

    --
    "Eve of Destruction", it's not just for old hippies anymore...
    1. Re:It would be interesting to know... by I'm+a+racist. · · Score: 3, Informative
      I haven't read the article, but I do have a degree in astrophysics, so I can guide you in how to calculate it.

      There are a few different ways of measuring magnitude (apparent, bolometric, etc). Bolometric is essentially the integral over all wavelengths. I'm guessing they didn't do a real bolometric measurement, but I could be wrong.

      Anyway, the relationship between intensity (I) and apparent magnitude (m) is
      m = -[19 + (2.5).log(I)]
      Intensity is in units of power/area, such as W/m^2 or ergs/cm^2 (cgs units are oddly popular in astronomy).

      If they did do a bolometric measurement, you can pretty easily manipulate this relationship to reflect that.

      Now, from the power, knowing the wavelength(s), and using the fact that the energy per photon is the frequency times Planck's constant... and thus you can find the number of photons per unit time per unit area. Which, when coupled with the known exposure time, will give you the total number of photons.
      --


      Down with Saudi Arabia!!!
    2. Re:It would be interesting to know... by Liquid+Tip · · Score: 5, Informative

      The best way is to download the processed HST images and see what the count rate is for a faint star. Then multiply by the gain (in the header of the image) which will give you the number of photons detected. A way to guestimate the number of photons is to compare the flux of the faintest star with the Sun. At the Earth's distance the Sun has a flux of 1.36x10^6 erg s-1 cm-2 and the apparent mag of the sun is V=-26.8. If we assume that we have a star with V=31 mag (the 50% completeness level is V=30.7 mag) then the flux recieved from the star is given by: F2/F1 = 100^((m1-m2)/5) where F1 and m1 are the flux and magnitude of the sun and F2 and m1 refer to the star. This gives 1.03x10^-17 erg s-1 cm-2. Convert the ergs into photons by the de Broglie frequency (E=hv) where we assume that a V-band photon has a wavelength of 550nm or a frequency of 5*10^14 s-1. Thus, each photon carries 3.61x10^-12 ergs which gives a rate of 2.85x10^-6 photons s-1 cm-2. So a 3.5 day exposure is 302400 secs and HST has an aperature of 240 cm so we get about 50000 photons at the entrance of the telescope. Remember.. detection of these sources means having a low background so that these photons are not lost in noise! I should also point out that HST does not leave the shutter open continuously for 3.5Hs, instead it takes a series of short exposures that are co-added. I hope this helps (and doesn't freak people out!)

    3. Re:It would be interesting to know... by Anonymous Coward · · Score: 1, Insightful

      How can you, having studied astronomy, having an understanding of the vastness of space, still participate in such worthless endeavors as racism? How can you consider that important, worthwhile, or right?

    4. Re:It would be interesting to know... by thynk · · Score: 1

      Ummmmm... so is that a lot or something? :)

      --

      Good judgment comes from experience, and a lot of that comes from bad judgment.
    5. Re:It would be interesting to know... by Liquid+Tip · · Score: 1

      Yeah.. that would help to know!

      To put everything into perspective, the full moon has a magnitude of -12.7 (so you can compare that to a light in your room) which gives roughly 1x10^12 photons over 3.5 days. Compare that to only 5x10^4 photons (in proper sig figs from our guestimation) from a 31th magnitude star!

      Think of how many photons are directed upwards from city lights and then scattered back down towards us, ruining dark skies, not to mention the waste of energy!

      Cats: You are on the way to destruction.

    6. Re:It would be interesting to know... by Anonymous Coward · · Score: 0
      And how does a simple political statement become a racist endeavor??? Could it be that he has issues with certain aspects of the Saudi government?? Or could it be that he's "down" and "hip" with Saudi Arabia??

      Or do you just have the kneejerk reaction of responding to anything you disagree with as racist. Why not? Works for Jesse Jackson, don't it??

    7. Re:It would be interesting to know... by Anonymous Coward · · Score: 0
      "by I'm a racist. (631537) on Sunday May 11, @12:10AM (#5929120)"
      (http://www.resistance.com/ethniccleansing/

      Thanks for noticing!

    8. Re:It would be interesting to know... by VanillaCoke420 · · Score: 0, Offtopic

      It's mindboggling indeed. I suspect that political views are, for some people, like religion. It requires them to throw overboard the ideals that made them turn to science (astronomy in this case) in the first place. It's weird. It's also weird to see him say, on his website, that he doesn't want hatemail... I guess hating is ok only sometimes.

    9. Re:It would be interesting to know... by Anonymous Coward · · Score: 0

      The idea that white people are better than blacks, or any other ethinc group you can find, is stupid, and you know that. Look at the world history, and tell me exactly how the actions of a certain ethnic group is better or worse than another. Everywhere on this planet, you will find ethnic groups, religious groups, or whatever categories you like best, that all have been doing bad things. Whites, blacks, asians. The worst thing with racism is that it doesn't require a lot of brain power to understand it's bullshit. It's not any more complicated to understand that, than to understand astronomy, so what the hell is wrong with you?

    10. Re:It would be interesting to know... by Anonymous Coward · · Score: 0

      Uh, the poster calls himself "I'm a racist", moron.

      Where do you get this stuff about Saudi Arabia. Keep sniffing paint thinner, it's doing you fiiiiine.

    11. Re:It would be interesting to know... by Anonymous Coward · · Score: 0
      On average, White people are better than Negroes. White people are smarter, more attractive, harder working, more compassionate, more law abiding, more charitable, and down right more likable than Negroes.

      Just ask yourself, would you rather walk through a Negro neighborhood or a White neighborhood? (I thought as much. At least you are honest with yourself.)

    12. Re:It would be interesting to know... by Anonymous Coward · · Score: 0
      Dr. White wrote that in the latest report from Science Weekly how Dr. Brooks found chimps to be smarter than Negroes.The full report will be published in September. Also a genetic link between Negro genes and idleness.

      Then I remembered a show which I saw last summer. I watched a PBS program about Koko the gorilla using sign language and so on, and among other things, they said this ape had an IQ of 85. The first thing that came to mind was the average American black IQ being 85 as mentioned in Charles Murray's The Bell Curve.

      Surely I couldn't have been the only one to take note, but I figured that if anyone complained, the news media wouldn't respond because it would be just too damned embarrassing to publicize if the nignogs demanded that this segment be edited out.

    13. Re:It would be interesting to know... by Anonymous Coward · · Score: 0

      Try reading through his journal entries. At first, I thought it was a sick troll dying to become the world's best flamebait. After reading through a lot of his comments and journal entries, it becomes apparent that he truly does believe what he posts.

    14. Re:It would be interesting to know... by Anonymous Coward · · Score: 0

      On average, a post like this would be a troll post. Therefore I should ignore it. Yes, the world would be perfect if we made decisions based on generalizations. Right.

    15. Re:It would be interesting to know... by Anonymous Coward · · Score: 1, Informative

      Oh yeah? Let me quote from the journal of that "I'm a Racist" dude:

      "Traits come in groups. More than one trait is needed to clearly identify a taxonomic class. Niggers have dirty skin, pubic hair on their heads, broad and flat noses, etc. Why can't being a lowlife, useless, stupid, lazy, criminal shitmonkey be considered part of such a group of common traits? Just because some things are negative we shouldn't consider them??

      As for the nature vs. nurture issue, we'll put that aside for this discussion (it's well outside the scope anyway). Suffice it to say that, if a nigger raises a nigglet, the point becomes moot.

      "Anti-racists" deny the facts of reality because they wish the world followed their ideal. I live in reality. In reality niggers/spics/kikes/chinks/dotheads/etcetera lower the quality of life for everyone. For that they should fucking die.


      How can someone be so fucking stupid and not realize that THEY are the ones lowering the quality of life for everyone? Whenever I've been ripped off in my life, it was a white man. I'm not that old okay, 38, but still I think stupid fucks like that guy and their sympathizers should get fucking locked up or at least sterilized. They make me ashamed of being white.

      It's just a game, yeah right. You do realize that kids love FPS games, huh? I'm against censorship, but at least we shouldn't treat it like any random game?! FUCKING BRAINLESS FOOL.

    16. Re:It would be interesting to know... by Anonymous Coward · · Score: 0

      You assume that he (she) is white, perhaps he (she) is not. Racism is not limited to whites. Turn on B.E.T anyday of the week.

    17. Re:It would be interesting to know... by Anonymous Coward · · Score: 0

      it's sad that fuckers like this can be smart enough to get a degree. you'd think that someone with that kind of degree would know that blacks are just as good as whites. asshole.

    18. Re:It would be interesting to know... by barakn · · Score: 1

      I think this guy may be an example of a freak-whore. I noticed that $$$$$exygal, the ultimate fan-whore, is in his freaks list. Oh, the irony.....

      --
      "I'm so moist I'm sticking to the leather." -Kermit the Frog on The Late Late Show
    19. Re:It would be interesting to know... by noda132 · · Score: 1

      Just how many photons they detected for the faintest star.

      Obviously... 1. I'm sure they got loads of 1-photon sources, and though doubtless they don't do much to the final picture, they definitely happened.

    20. Re:It would be interesting to know... by Roto-Rooter+Man · · Score: 1

      it becomes apparent that he truly does believe what he posts.

      That's odd. It's apparent to me that he's a good troll, and one who's testing if Slashbots are truly as tolerant of the ideas of others as they claim to be. Of course, the answer is no. As such, he's fashioned a likable character who "just happens" to be racist. It also has the added benefit of getting constantly modded up and down, as the ideas are solid, but the racism sparks a reflexive mod-down. If everyone truly got over the racism and stopped commenting on it, I suspect we'd see "I'm a racist" become even more blatantly racist in an attempt to get attention, or simply disappear.

      Of course, as another troll, I highly approve of what he's doing. A large number of people on Slashdot, however, take everything too seriously [particularly this amateurish website], and can't comprehend that someone else may not actually be who they seem. Trolls are not any dumber than other Slashdot readers; we are perfectly capable of creating the illusion of reality instead of being a blatant obscene crapflooder. I smile when I see trolls; why can't others? Too many people are out there looking to be offended.

      --

      The goatse guy for president. Win one for the gaper!
  9. *takes lense off* by gnujoshua · · Score: 1

    What fstop was that?

  10. WOW by oaf357 · · Score: 0, Troll

    That is some very wild looking photography. I wonder if I could download the entire pic and use it as a wallpaper (I'm kidding).

    1. Re:WOW by jarrell · · Score: 1

      Yea. The hubble site has it in multiple formats. The 738K "large print" format would make a decent bit of wall paper, but if you're a masochist, or just really into astronomy, you can tweak your own from the 127Meg raw tiff...

  11. The good side of S.A.R.S. by Anonymous Coward · · Score: 0, Troll

    I was thinking about SARS, and I actually think that a world SARS epedemy could solve a lot.

    Why is that? Well - I'm speaking of a cynical point of view.

    During the 80'ies and 90'ies Denmark has been recognized to be the best country in the world in terms of social welfare. But a new problem is rising in Denmark. The workers that made great welfare in the 80'ies are beginning to age and retire, but they have been lazy in terms of breeding.
    I was born in 1984, and I am currently under education. Already now, I can feel problems. The government is cutting everywhere - including education. Why? Possibly because the number of workers in Denmark is steadily dropping, and our former workers are transforming into retired seniors. Now these seniors don't contribute anymore, they're an expense, since they receive social retirement money. Over $1.000 pr. month.
    This means, when I am going into the working market - becoming an adult, I'll probably have to work more and pay more tax than my parents - all to finance the growing group of elderly people.
    Why is this group representing a bigger share of the population than before? Well - people have less children than 50 years ago, and they live longer due to scientific/medical evolution.

    So where does SARS step in?

    We'll - if we look at it from a pure cynical view, SARS supposedly kills 30-50% of seniors infected, while only 3-6% of young people infected has to go....
    I'm just picturing a blooming economy, a reduction in work, better schools, better hospitals, better healthcare, lower rent / more housing available, etc... The current danish state is going downhill because of the growing amount of old people. Why the hell didn't they have more children? Why didn't they secure the future economy? I feel let down by the older society...

    Yes, it is egoistic, but the danish society was perfectly aware in the 70'ies that problems was arising within the next 30 years due to the falling number of births, but they chose to spend money here and now, and look. This is only the top of the iceberg. The worker/senior rate will top in 2015. So somehow, I would welcome SARS, as it solves a great threat to the danish economy. Most likely all seniors will disagree with me, but that's just their point of view.

    So I am asking you? Would you prefer a world wide SARS epidemy, if you could choose?

  12. Details on the exposure techniques? by d-rock · · Score: 4, Interesting

    3.4 day exposure? Even for a space-based platform, that has to be really stable to produce a good image. Does anyone out there have any info on how they maneuver the telescope to keep it pointing at the same point while minimizing shifts in the field?

    Derek

    --
    Don't Panic...
    1. Re:Details on the exposure techniques? by ChadN · · Score: 2, Informative

      While I'm no expert, I believe the answer is simply "gyroscopes". Very good ones, I'm sure. Also, they use reference stars to correct the gyroscopes when they drift.

      --
      "It's overkill, of course. But you can never have too much overkill." - Anonymous Slashdot Coward
    2. Re:Details on the exposure techniques? by deathcow · · Score: 5, Informative

      Many spacecraft have small jets that push them into different positions in space. Hubble has no jets because the exhaust gas from jets could damage its delicate mirrors. Instead, Hubble uses momentum to move.

      When Hubble needs to move to a new target, engineers on Earth radio a signal to the HST flight computer. The flight computer then activates the Reaction Wheels.

      Reaction wheels are heavy fly wheels that spin. As they spin, the momentum from their motion causes the telescope to move. There are four Reaction Wheels. By spinning each one at a certain speed and in a certain direction, engineers can point the telescop e anywhere they want.

    3. Re:Details on the exposure techniques? by d-rock · · Score: 4, Interesting

      Interesting. I was actually thinking more along the lines of automatic compensation, but I hadn't even thought about gyroscopes vs. impulse jets. I poked around a little on the hubble site for the instrumentation and flight computer and I found the handbooks for the instruments at this site. Appearently, the gyroscopes are used for coarse motion detection and the FGS uses constellational guidance. The manuals actually make a pretty interesting read.

      On a side note, a constellational guidance is related to how head mount displays like UNC's HiBall work.


      Derek
      --
      Don't Panic...
    4. Re:Details on the exposure techniques? by LMCBoy · · Score: 4, Informative

      3.4 days is the effective exposure time, from stacking many shorter exposures. If HST integrated for 3.4 days without reading out the CCD, the entire chip would be saturated with cosmic rays, not to mention the fact that the Earth is typically in the way for half the orbit(*), limiting individual exposure times to about an hour or so.

      (*) except for a small patch of sky called the CVZ: continuously visible zone

      BTW, if you're keeping score at home, 30th magnitude is 1 trillion times fainter than the human eye can see!

      [*shameless plug* Tom Brown is using my thesis code to analyze these data :) ]

      --
      Liberal (adj.): Free from bigotry; open to progress; tolerant of others.
    5. Re:Details on the exposure techniques? by Anonymous Coward · · Score: 1

      The full ACS image is about 3.1 arcminutes square, the size of a sand grain held at arm's length against the sky.

      I downloaded this very large image. Wow...

      There are so many stars and so many galaxies in that expansive image. What really strikes me is to try and imagine if I held up a grain of sand and it could somehow act as a lense into my brain that allowed my mind to see that image/all that detail, then to move across the night sky. There's so much out there, what is visibly represented is mind boggling to me, and that is probably just a small fraction of reality.

      As some dumb little monkey in the big big world of ours which I'm confronted with every day. Things like this are really humbling. I feel so infinitesimally tiny and insignificant. I only wish I had time enough in this realm to really explore and truely understand its nature.

    6. Re:Details on the exposure techniques? by Hatechall · · Score: 1

      I'm guessing a multi-million dollar orbiting telescope might help.

    7. Re:Details on the exposure techniques? by Martin+Blank · · Score: 1

      Many spacecraft have small jets that push them into different positions in space. Hubble has no jets because the exhaust gas from jets could damage its delicate mirrors.

      Another reason that gyros are used is much more practical: fuel storage limitations. For a satellite that is to be in orbit for years and will be constantly redirected, the fuel required for something like that would be many times the mass of the satellite, and thus impossible to put into orbit.

      --
      You can never go home again... but I guess you can shop there.
    8. Re:Details on the exposure techniques? by supernova87a · · Score: 3, Informative

      The Hubble has an instrument called the Fine Guidance Sensor (FGS) package. Given two stars that are bright enough near the sky location of your desired target, Hubble will be able to guide to within sub-pixel accuracy for as long as you like.

      If only one star is available, guiding is still possible, but the field may slowly rotate, since one star only provides one of the two needed pointing constraints (of position and orientation).

      A big project in preparation for Hubble was the creation of the Hubble Guide Star catalog, exactly for this purpose -- to make sure that given what people would want to observe, there would always be enough guide stars within an acceptable distance!

      for more information, see here if you're interested! If you're ambitious, you can even read the instrument handbooks for yourself: here

    9. Re:Details on the exposure techniques? by pyrrho · · Score: 2, Interesting

      Then I assume LMC means Large Megellanic Cloud.

      --

      -pyrrho

    10. Re:Details on the exposure techniques? by LMCBoy · · Score: 1

      ding, ding! we have a winner. :)

      --
      Liberal (adj.): Free from bigotry; open to progress; tolerant of others.
    11. Re:Details on the exposure techniques? by pyrrho · · Score: 1

      btw, Kstars looks cool thanks for the info (via your sig).

      Have you checked out stellarium and celestia? Both are interesting GPLed astro programs, the first being a planetarium project not unlike Kstars, and celestia being a solar system/galactic simulator of great coolness. If not, I recommend a quick look.

      --

      -pyrrho

    12. Re:Details on the exposure techniques? by LMCBoy · · Score: 1

      Celestia is extremely cool. :)
      I haven't tried Stellarium, thanks for the tip.

      --
      Liberal (adj.): Free from bigotry; open to progress; tolerant of others.
  13. All in all... by skogs · · Score: 4, Interesting

    It is still pretty incredible...pointing an object the size of a bus and accurately focusing it on something the size of a spec of sand...really, really, really far away. All while moving at a relative 26,000 miles an hour or whatever to keep it up in the sky...Not to mention the orbial speed of the earth itself... Only took 8 guys, several computers, and millions of dollars worth of equipment. Oh yeah, and that one maintenance run made a few years back to keep it pointing straight.

    --
    Who is this that even the wind and the waves obey Him? Surely this computer must submit also!
    1. Re:All in all... by plip · · Score: 3, Informative


      Not Several Millions, we're talking Billions...

      According to http://hubble.nasa.gov/faq.html it cost $1.5 billion Plus another $230-250 million each year for maintenence. Estimated costs to fix the lens problem on the telescope were $20 million. Since the Hubble was launched in 1990 and is planned to operate until 2010, that's $230M per year for 20 years = $4.6 Billion + the $1.5 Billion initial cost. That's a total cost of operation equal to $6.1 Billion (low estimate that doesn't include the cost of engineering and scientific knowledge needed for this to happen).

      In my opinion, the information it sends back is priceless to humanity, and well worth whatever cost it takes.

    2. Re:All in all... by RicktheBrick · · Score: 2, Insightful

      Is this information needed now? If the space elevator is invented and there are plenty of people who think it will be invented, than what will the cost of finding this information? I think it would be a magnitude less and there would be less loss of human life too.

    3. Re:All in all... by supernova87a · · Score: 1

      this is not for dissemination to the general public -- according to the scientist who designed the camera that took this picture, if you had sent to the Hubble a solid piece of gold that weighed the same amount as the instrument (which was about as large as a telephone booth), you would have saved approximately 30x the money...

      but you're right, it *was* worth it!!!

    4. Re:All in all... by Anonymous Coward · · Score: 0

      These are 2 different things though. NASA just happens to deal with both. Astrophysics and Astronomy should be one dept., whil transport and exploration should be another. We really need both of them though.

      And, I would like to see an attempt made for building this space elevator. That is the only way we will increase our presence in outer space. We will be able to build bigger ships, since they won't have to land or take-off from Earth. There even could be a hotel up there on the end of the line.

      I also think that multiple cars could go up and down at the same time, kindof like a train. And then they would come down together as well.

    5. Re:All in all... by plip · · Score: 1


      This is silly. It's like asking "Why build a space probe when we will be flying to other planets someday?" We need this knowledge, and the sooner the better. It will help us understand things that will help us in the future.

      How do you measure the value of knowledge? Whether it is in bits and pieces, or leaps and bounds, all of it matters.

    6. Re:All in all... by benna · · Score: 1

      NOOOO, what will we do in 2010 when we are done with it. It is really usefull. This is a serious question.

      --
      "It is not how things are in the world that is mystical, but that it exists." -Ludwig Wittgenstein
    7. Re:All in all... by Muhammar · · Score: 1

      1. Gold is not expensive. A lot of common chemicals (catalyst, some elaborate ligands, advanced intermediates etc) can be more than 20x more expensive than gold by weight. Almost every university and industry lab doing synthetic organic chemistry is using them.
      2. Shuttle is extremely costly but the science done there is ho-hum and until recently a lot of it was not even done on level publishable in decent peer-revied journals.

      --
      I doubt that we will ever figure out - and I suspect that even if we did figure out we couldn't do much about it
  14. and NASA couldn't afford 1600... by neurostar · · Score: 4, Funny

    And, to think I used to complain about having to get the tripod out for exposures that were longer than 1/8th of a second! I'll never comlpain about slow film or lenses again!

    Yeah, and you'd think NASA could afford 1600 ASA film for the price they paid for hubble...
    I mean geez!

  15. Shameless karma whoring: by bertok · · Score: 4, Informative

    Direct link to the full-resolution JPEG. (~4.9MB)

    http://imgsrc.hubblesite.org/hu/db/2003/15/images/ a/formats/full_jpg.jpg

    1. Re:Shameless karma whoring: by paiute · · Score: 1

      The image "http://imgsrc.hubblesite.org/hu/db/2003/15/images /a/formats/full_jpg.jpg" cannot be displayed, because it contains errors.

      Man, that is high resolution!

      --
      If Slashdot were chemistry it would look like this:Cadaverine
    2. Re:Shameless karma whoring: by Biogenesis · · Score: 5, Funny

      Thanks for the links, i've got it downloading in a new tab ri Segmentation Fault

    3. Re:Shameless karma whoring: by adamruck · · Score: 1

      well I waited for the whole thing to download and it looks like every other hubble picture ive seen just a whole lot bigger. Guess it shows im not an astronomer.

      --
      Selling software wont make you money, selling a service will.
    4. Re:Shameless karma whoring: by Anonymous Coward · · Score: 0

      Wow. Mozilla hasn't shit it's pants yet - but it also hasn't finished downloading.

  16. Can't resist... by moertle · · Score: 0, Funny
    ... who headed the eight-person team that took the picture ...
    So how many astronomers does it take to change a light bulb?
    --
    I hold a patent on sigs...
  17. hubblesite.org news release by SILIZIUMM · · Score: 4, Informative

    See also the press release with tons of photos. Enjoy your new wallpaper ! :)

  18. hubblesite.org by zaneIO · · Score: 5, Informative

    Here is a link to a higher resolution image.
    Hubblesite.org

    1. Re:hubblesite.org by Anonymous Coward · · Score: 1

      Oh please! Don't link to 120MB files. Hardly anone here needs to be downloading such a large image. Yes, it's cool, but you're totally wasting bandwidth. If you *must*, at least let someone set up a BitTorrent link first.

  19. exposure time misleading by jeffrey1681 · · Score: 5, Informative

    The image is not actually a single exposure of 3.5 days in duration, but is actually made from 250 separate exposures taken from Dec. 2 to Jan. 11, 2003. The total exposure time was 3.5 days.

    For those who are interested, the original hubble press release is located here.

    The site includes the image in a variety of different formats, including a 123 MB tiff file.

    1. Re:exposure time misleading by u19925 · · Score: 1

      It is doubly misleading. In a single exposure, the SNR increases as the exposure time. On the other hand, when you combine multiple images, you get noise from each image. Thus signal increases linearly and noise increases as a square root of the number of images combined. If all (250) images had identical exposure time, the resulting image has 16 times less SNR than a single image of 3.5 days exposure. This is the worst case and in this case, it is equivalent of about 5 hours exposure. So effectively, they wasted 3 days of hubble time!

  20. Philosophy: The Deepest Thought Ever Thunk by Anonymous Coward · · Score: 2, Funny

    Aristotle writes: "Philosophers using the Bubble Head Telescope's powerful new Advanced Cognition for Sophistry (ACS) have taken the deepest thought ever thunk. The 3.5-day (84-hour) idea captures notions as powerful as 31 SBU (Silent Bob Units), according to Plato (The Platonic Academy), who headed the eight-person team that contemplated the thought."

  21. ...hubblesite.org collapses into a singularity by Leeji · · Score: 4, Funny

    For the love of all things scientific, have mercy on their 122MB TIFF image.

    And to think that we've turned servers into slag by Slashdotting a 43kb page.

    --
    It all goes downhill from first post ...
    1. Re:...hubblesite.org collapses into a singularity by maxentius · · Score: 1

      I'm getting it at 11K per second. Pretty good, considering.

      About 49 minutes to go.

      --
      Imagine a Beowulf cluster of neurons.
  22. Streaks by stratjakt · · Score: 2, Insightful

    If you look at the image, there are some odd streaks that go from red to blue (or blue to red).

    I'm just curious here, what are they? I thought maybe it could be a bit of space debris that whizzed in front of the camera, but with an exposure of 3.4 days, the streak would go from one side or another.

    What moves that far in 3.4 days? A comet? A meteor? A star?

    And that big bright cluster in the lower bottom, what's that? It looks pretty close galaxy-wise.

    It's a neat pic for sure, a little blurry, which makes it less jawdropping than other hubble efforts but makes sense for a 3.4 day exposure.

    Note - I didn't make any goatse or Uranus crack this whole post. You're welcome.

    --
    I don't need no instructions to know how to rock!!!!
    1. Re:Streaks by localghost · · Score: 2, Interesting

      If you look at the image, there are some odd streaks that go from red to blue (or blue to red).
      I'm just curious here, what are they? I thought maybe it could be a bit of space debris that whizzed in front of the camera, but with an exposure of 3.4 days, the streak would go from one side or another.


      The streaks are probably something that moved, though some of them seem brighter in the center, which would indicate it was oscillating. I'm not exactly sure. Anything could move any distance in 3.4 days.

      And that big bright cluster in the lower bottom, what's that? It looks pretty close galaxy-wise.

      The bright cluster is probably a globular cluster, which is a tight grouping of old stars. It's most likely in our galaxy.

      It's a neat pic for sure, a little blurry, which makes it less jawdropping than other hubble efforts but makes sense for a 3.4 day exposure.

      Scale it down and it's definitely not blurry. At least not the 6116x7014 image.

      lower bottom

      What the hell?

    2. Re:Streaks by Liquid+Tip · · Score: 5, Informative

      The "streaks" centering on stars are diffration spikes from the secondary mirror support. The colour alternates as different wavelenghts cause different diffration spacings.

      The big bright cluster is actually a member of Andromedae (M31). Very impressive! The appearance of fuzziness is because the CCD oversamples the resolution of the telescope - which is necessary for good photometry - if you want it "sharp" then just bin the pixels by 2x2 or 3x3 or whatever looks best!

  23. Actually, rotates, not moves by neurostar · · Score: 4, Informative

    As they spin, the momentum from their motion causes the telescope to move.

    Well, it's techincally a litter different than that. The wheels don't actually cause hubble to translate within a plane. Instead they rotate hubble. By turning the spinning wheels, a torque is exerted on hubble, causing it to rotate.

    neurostar
  24. What's up with the points? by Jerf · · Score: 3, Interesting

    Something I've wondered for a while... what's up with the points coming off the stars? I've always accepted it when I see it with my own eyes because I don't expect my own eyes to be optically perfect, so I always thought it was distortion, but looking at the full image I see that the brightest stars once again have points coming off of them in four directions. Typically they are directly up, down, left, and right, but in that image, they appear to be about five to ten degrees off that.

    The biggest example I see is about 3/4s of the way to the right and about 1/5 of the way down on the image, where there is a huge-looking star.

    Why four points? Why do we see them even when the star itself is not in the picture (look on the top border for examples, like the one almost directly in the middle)? I guess I would expect that if the light source is too bright the spread would be in a circular formation and simply blur the star, not blur it in just those four directions so much stronger then the rest.

    Is it just QM at play? If so, why it is almost always directly up, down, left, and right, instead of random and perhaps even changing over time directions (which probably would get right back to simply looking blurred)? Detector flaws?

    1. Re:What's up with the points? by jeffrey1681 · · Score: 2, Informative

      Almost all modern optical/IR/X-ray telescopes use a CCD to capture the light that is incident on the telescope. Each pixel in the CCD can hold a certain number of electrons (which are produced when a photon hits the pixel). When that number is exceeded, usually through too many photons hitting the same pixel as in this case, the electrons spill over into the surrounding pixels. This is called blooming and produces the spikes that you see in the image. So basically, the spikes mean that the star is overexposed.

    2. Re:What's up with the points? by phliar · · Score: 1
      They're artifacts caused by the supports for the secondary mirror.

      You know when you're watching a movie, if the lens points close to the sun, you see a sequence of little polygons move across the field? That's the image of the actual aperture being reflected off the many glass/glass and glass/air surfaces in the lens. (Modern lenses are complex, and are made of many "simple" lenses stacked together.)

      Since the secondary mirror is in the "opening" of the telescope, it needs to be supported. The supports cause those artifacts.

      --
      Unlimited growth == Cancer.
    3. Re:What's up with the points? by jstott · · Score: 2, Informative
      Why four points? Why do we see them even when the star itself is not in the picture (look on the top border for examples, like the one almost directly in the middle)?

      No quantum mechanics, just plain ol' classical optics. Those are diffraction patterns. Crosses are the Fourier transform of a square, so I assume their aperature stop is a square.

      -JS

      --
      Vanity of vanities, all is vanity...
  25. Very impressed... by Dynedain · · Score: 2, Insightful

    I know there are countless galaxies out there...but they are so far away, I was extremely surprised at how many galaxies I could see in the big 4MB JPEG.

    --
    I'm out of my mind right now, but feel free to leave a message.....
    1. Re:Very impressed... by LMCBoy · · Score: 5, Interesting

      Actually, the really unique thing about this image is the stellar populations. The stars you see in the image are almost all in the Andromeda galaxy (aka M 31), seen here.

      M 31 is 2.2 million light-years away. This is the galaxy that Hubble originally resolved into stars, thereby settling the Shapley-Curtis debate on the true scale of the Universe. However, the stars Hubble saw were the very brightest supergiants in M 31. In this HST image, we see stars 2 magnitudes fainter than the ancient main-sequence turn-off; i.e., stars which are intrinsically fainter than our Sun! This lets us learn a lot about the ages and chemical composition of M 31's halo stars, which turn out to be quite different from the stars in our halo (our halo is entirely composed of ancient, metal-poor stars; M 31's halo contains stars that are only 6 Gyr old, and much more metal-rich than our halo).

      I heard Tom Brown give a talk on this work last week; very cool stuff.

      --
      Liberal (adj.): Free from bigotry; open to progress; tolerant of others.
  26. i still think this image is deeper... by mattkime · · Score: 3, Funny
    --
    Know what I like about atheists? I've yet to meet one that believes God is on their side.
    1. Re:i still think this image is deeper... by Anonymous Coward · · Score: 0

      I was worried - I was expecting a goatse link

  27. Idiotic resolution by Anonymous Coward · · Score: 0

    Or you can download the 738.4 kB version and do the pixel doubling yourself.

  28. This has to be the most expensive by jkauzlar · · Score: 5, Funny

    desktop background ever created :) Its sure worth the effort, however!

  29. It's due to the way telescopes are built. by Anonymous Coward · · Score: 5, Informative

    Modern optical/IR/UV telescopes typically have a large primary mirror, which reflects light back to a smaller secondary, which reflects the light through a small hole in the primary to the detectors. The secondary is supported by little rods. It is diffraction of light by those supports which cause stars to have distorted shapes.

    (Astronomers understand the diffraction issues very well... it's usually not a problem; it just looks weird.)

    - A friendly neighborhood astrophysicist

  30. The full size TIFF screensaver? by Anonymous Coward · · Score: 2, Interesting

    I just thought about how detailed the full size pic is, and how to appreciate that without a poster printer. I'd like to see something similar to osx's default screensavers (with the softly zooming pictures of trees/beach, etc) and have it use this picture.

    I'd like to see it zoom in to the picture, while also changing x/y of the camera on a spline (etc). And each time choose a different starting point, and make it's speed adjustable.

    All of those high-res pics are beautiful! maybe i'm 'a gonna dust off the 'gl..

    1. Re:The full size TIFF screensaver? by spydir31 · · Score: 1

      You might be interested in glslideshow from xscreensaver which does this.

  31. So awesome it's philosophical. by glrotate · · Score: 4, Insightful

    The grandeur of such an image almost forces one to reasses their place in the world. To think that the area in the photograph is equivalent to the area covered by a grain of sand at arms length is mindnumbing. The universe is unbelieveably amazing.

    1. Re:So awesome it's philosophical. by Anonymous Coward · · Score: 1, Funny

      The grandeur of such an image almost forces one to reasses their place in the world...The universe is unbelieveably amazing.

      That's excatly what I said when I saw goatse.

    2. Re:So awesome it's philosophical. by thynk · · Score: 1

      Yeah, Kinda makes me feel really small and meaningless, but at the same time - glad to be a part of something so beaufiful.

      (translated into redneckeese: Yup, shore is purdy.)

      --

      Good judgment comes from experience, and a lot of that comes from bad judgment.
    3. Re:So awesome it's philosophical. by Threni · · Score: 2, Funny

      >The grandeur of such an image almost forces one to
      >reasses their place in the world

      Almost, but not quite. I'm pretty damned cool.

    4. Re:So awesome it's philosophical. by Anonymous Coward · · Score: 0

      You might enjoy this article from The Atlantic:

      http://www.theatlantic.com/issues/2002/07/benson .h tm"

    5. Re:So awesome it's philosophical. by kindbud · · Score: 1

      I think it's amazingly unbelievable.

      --
      Edith Keeler Must Die
  32. Bring out the telescope mirrors! by migstradamus · · Score: 1

    "Your Web browser appears to be set to block cookies. SkyandTelescope.com requires a cookie file, though you may visit the site without supplying any personal information, rendering the cookie anonymous. If you believe you reached this page in error, try clicking one of the links below to access our site."

  33. Man... by nate+nice · · Score: 1

    ...and I can't even find my keys!

    --
    "If you are a dreamer, a wisher, a liar, A hope-er, a pray-er, a magic bean buyer ..."
  34. the deepest photo that will *ever* be taken by dh003i · · Score: 3, Informative

    Will be about 20 billion light years, since we think the universe is about 20 billion years old.

    For an interesting article, see:

    http://www.sciam.com/article.cfm?colID=1&article ID =000F1EDD-B48A-1E90-8EA5809EC5880000

    On parallel universes. Very interesting reading. If you're at a university, you will be able to browse the site's archives and access the nice PDF version of the article (which has the pictures supersized to full-page size).

    1. Re:the deepest photo that will *ever* be taken by LMCBoy · · Score: 4, Informative

      You're right, if you take deepest image to mean "image of most distant objects" instead of "faintest objects". However, the Universe is 13.7 Gyr old, not 20 Gyr.

      Here's your deepest image then:
      http://map.gsfc.nasa.gov/m_ig/020598/020598 _ilc_64 0.jpg

      That's from the recent WMAP mission, which mapped the cosmic microwave background in exquisite detail, pinpointing the age of the Universe (and many other cosmological parameters) to high precision. You're looking at an all-sky image of the Universe as it looked when it was 100,000 years old, and became transparent for the first time. IOW, you are literally seeing the fires of creation.

      --
      Liberal (adj.): Free from bigotry; open to progress; tolerant of others.
    2. Re:the deepest photo that will *ever* be taken by thynk · · Score: 1

      Corrected Link to Article In case you don't catch the space in the orignal one, or are just to lazy to cut and paste :)

      --

      Good judgment comes from experience, and a lot of that comes from bad judgment.
    3. Re:the deepest photo that will *ever* be taken by Anonymous Coward · · Score: 0

      You can be serious, 20 Billion years old. REALLY!
      I mean how can countless million Christian, Muslim, Jewish, *insert other creation based religion here* people be wrong.

      then again most of the stuff they believe in comes from book that has been re-written countless times and translated into / from so many languages, its not like you can take whats in it as *gospel*

  35. Wow... I love science by doormat · · Score: 1

    And to think any one of those smaller stars could have a planet orbiting it.. with its own culture and civilization and technology. Wow...

    --
    The Doormat

    If you're not outraged, then you're not paying attention.
    1. Re:Wow... I love science by Exiler · · Score: 1

      With their own wars, their own facists, their own ignorance, and death, and torture, and pain, and broken hearts... Wow, I depress myself too easily.

      --
      Banaaaana!
    2. Re:Wow... I love science by doormat · · Score: 1

      You need to get laid my friend. =^) j/k. Yea, you have to take the good with the bad. Existing is still far better than not existing, at least for me.

      --
      The Doormat

      If you're not outraged, then you're not paying attention.
  36. Damn, by fireman+sam · · Score: 5, Funny

    I'd hate to have to hold my finger on the button for that long without shaking the camera.

    *This is a lame joke*

    --
    it is only after a long journey that you know the strength of the horse.
    1. Re:Damn, by Anonymous Coward · · Score: 0

      You use a cable release, moron.

  37. Re:Globular Cluster by Kotetsu · · Score: 1

    Actually, if you read the article, that globular cluster is actually one of M31's clusters. The brightest globulars around M31 are about 13th magnitude, so they are visible in amateur telescopes (although they look like faint stars).

    It does show impressively how good the resolution of the photograph is.

    --

    "Bite me, it's fun!" - Crowe T. Robot
  38. A Galaxy ... by BobLenon · · Score: 1

    So I dl'd the huge tiff. Awesomeness. But I cant quite see that Galaxy...

    Long, Long ago, far, far away ...

    Rifed with Intergaltic Civil War.

    Sorry, I mean Gentrification.

    I guess 25 Million (?) light years just isnt enough ;(

    --

    /* Lobster Stick To Magnet!*/
    1. Re:A Galaxy ... by UnixRevolution · · Score: 2, Interesting

      Don't forget, this is only 3.1 arcminutes^2 of the sky. that's the size of a grain of sand held at arms-length against the sky, according to the article. That leaves a ton of sky still unseen.

      --
      You like your new Mac more than you like me, don't you, Dave? Dave? I asked...She said Yes.
  39. Mirror of full JPG by idiot900 · · Score: 5, Informative


    http://wuarchive.wustl.edu/users/tom/mirrors/hub bl e/full_jpg.jpg

    is a mirror of the full JPEG - about 5M. Enjoy.

  40. Re:Globular Cluster by localghost · · Score: 1

    The article was slashdotted, so I just guessed from pictures. It was hard to tell, but it looked like it was in front of the galaxy. I know nothing about astronomy, though.

  41. Not all scopes exhibit diffraction spikes. by fmaxwell · · Score: 5, Informative

    Something I've wondered for a while... what's up with the points coming off the stars?

    As was mentioned in another post, those are diffraction spikes from the supports for the secondary mirror.

    Newtonian reflectors and classical Cassegrain telescopes support their secondary mirror with "spiders" that produce diffraction spikes. There have been various efforts over the years to eliminate these from that type of telescope. One method is to seal the tube with an optical flat (a flat piece of optical glass) which supports the mirror. The trade-offs include longer times for the scopes to reach temperature equilibrium, distortion from imperfections in the optical figure of the flat, and slight light loss. Other attempts have included the use of spiders with curved support arms, which reduce or eliminates spikes at the cost of slightly degraded overall image contrast.

    Other telescope types, such as refractors, Maksutovs, Schmidt-Cassegrains, and Yolo reflectors have no diffraction spikes, but they are all more optically complex (Yolos, for instance, require toroidal mirrors) and are more difficult to produce as a result. Refractors have the added problem of chromatic abberation, which is the fringing of color on the edge of bright objects. Various complex, multi-element objectives have been developed to reduce, or even practically eliminate, this problem. The problems are optical complexity, cost, and light loss. Figuring a 3-element objective lens for a refractor means grinding six optical surfaces with precise curves. Compare that to a Newtonian which has a single parabolic primary mirror and a flat optical secondary.

    There are many other telescope types than the few popular types I mentioned here and each have their proponents. Most designs that have survived the test of time can be made to perform well, but each has trade-offs.

    1. Re:Not all scopes exhibit diffraction spikes. by CaseyB · · Score: 1
      Aren't the diffraction spikes a predictable optical effect based on the star's brightness? Why isn't the effect corrected out of the image in postprocessing?

      I suspect that they leave them in because it looks dramatic and romantic for press releases. :)

    2. Re:Not all scopes exhibit diffraction spikes. by fmaxwell · · Score: 2, Informative

      Aren't the diffraction spikes a predictable optical effect based on the star's brightness? Why isn't the effect corrected out of the image in postprocessing?

      Subtracting data from scientific images is not a good idea. What if there is a dimmer star hidden in a diffraction spike? The next image of that section of sky is unlikely to be taken by a scope with diffraction spikes rotated relative to the former. Then, suddenly, they show a star that was "missing" on the post-processed image. At the very least, they waste time thinking that they have discovered a nova or supernova. At the worst, they announce this "finding", costing the scientific community time and money.

  42. Big Picture... by HobbitGod42 · · Score: 5, Interesting

    Does anyone know if there is a BitTorrent file out for the 128mb TIFF? the nasa servers are a bit slow and I feel my hardware cycles and bandwidth could be of use...

  43. daaaammn by Anonymous Coward · · Score: 0

    i just set the wallpaper to the 4 MB .jpg and X took it. it is amazing

  44. Holy cow! by polymath69 · · Score: 4, Funny
    Is that a Klingon Bird of Prey out in the distance?

    Unretouched excerpt from full-resolution image.

    --

    --
    I don't want to rule the world... I just want to be in charge of mayonnaise.
    1. Re:Holy cow! by Liquid+Tip · · Score: 1

      Ha! That's too funny. Can you make zoomed out jpeg of the region to find it?

    2. Re:Holy cow! by polymath69 · · Score: 1
      Can you make zoomed out jpeg of the region to find it?

      Not sure what you mean. If you're asking, where in the original picture is this subimage, it's in the top slice, and almost all the way to the right, at least at my screen's resolution. At any resolution, it's bound to be pretty near the top right corner.

      --

      --
      I don't want to rule the world... I just want to be in charge of mayonnaise.
    3. Re:Holy cow! by yerricde · · Score: 1

      Not sure what you mean [by "zoomed out jpeg"].

      Circle it in the original image, and then place it side-by-side with the detail image.

      --
      Will I retire or break 10K?
  45. Out of date knowledge by A+nonymous+Coward · · Score: 1

    I believe the current estimates are 13.5 or 14 billion years, and have been for a couple of years.

    1. Re:Out of date knowledge by Anonymous Coward · · Score: 0

      don't worry that this kid's MO; posting out of date or inaccurate "Facts" to get modded up

  46. 122.75 MB TIFF and More! by Nintendork · · Score: 2, Informative
    This is the official site where the photos are.

    -Lucas

  47. mmmmm... by djocyko · · Score: 1

    Milky Way....

  48. MOD PARENT DOWN. by Anonymous Coward · · Score: 2, Informative

    Moderators: Please don't encourage this guy in any way, even if this comment of his may very well contribute to the technical discussion.

    He doesn't deserve positive karma until he learns some respect. When he learns to treat people of all colors as he wishes to be treated himself, then perhaps he can contribute to the discussion in a worthwhile manner.

    What goes around, comes around. Paranoid delusions about people of other races (sexes / political and religious beliefs) are so 1700's and have no place in an advanced civilisation.

    1. Re:MOD PARENT DOWN. by Anonymous Coward · · Score: 0

      Is it possible the name is sarcasam ala "Rising Sun".

      People are so blind as to what true colorless society means. My son was being harassed so he replied as he was taught, "So what, you're Muslim." He meant ... color, race, religion don't matter stop harassing me for my ethnicity. Apparently it did matter to his teacher. Of course it was never an issue the past weeks and months while he was harassed for being French. It's fine to harass someone if they are white and Christian. Everyone panics though if you're not. Martin Luther King's Dream is so difficult to achieve. sigh...

      So is it possible, "I'm a Racist?" Because I've taught my children to acknowledge race has no bearing.

  49. Better - MOD CHILD UP by Anonymous Coward · · Score: 0

    AC is absolutely right. Please mod up.

  50. deepest photo?? by Anonymous Coward · · Score: 0

    does this mean that goatse.cx is now the SECOND deepest photo ever taken?

  51. Mod this racist bastard down by Anonymous Coward · · Score: 0

    For a guy who is supposedly an astrophysicist, he sure has a really low level of intelligence and a high level of ignorance.

  52. Mods, Please Mod Moronic Parent Down by Anonymous Coward · · Score: 0

    We don't need any racists here. They are stupid and smell bad.

    1. Re:Mods, Please Mod Moronic Parent Down by Anonymous Coward · · Score: 0

      Why do his personal opinions and feelings have anything to do with how smart he is? Why does the fact that he is or is not racist make his comments not interesting? You hate racists.. Well, you're just as bad as them for hating anybody in the first place. Hate breeds hate.. So why don't you build a bridge and show you're a "better person" than him?

  53. Reaction wheels?!? by Anonymous Coward · · Score: 0

    That's cool! But what do the little hamsters eat?

  54. dickhead by Anonymous Coward · · Score: 0

    YOUR forfathers brought them here from Africa. fuckwit.

  55. Re:Where is CowboyNeal? by Anonymous Coward · · Score: 0

    I demand more information!

  56. The sad thing is by Sycraft-fu · · Score: 1
    This is a lame joke

    Because of the nature of some posters/moderators on /., you felt that was a necessary fact to point out.

  57. What, are you dense or something? by Sycraft-fu · · Score: 0, Offtopic

    It's a game. Click the link. A very politically incorrect game but so what? Not the first we've seen (Redneck Rampage to name just one other). For crying our loud, people get so touchy any time anyone tries to poke fun at race. Get over it.

    1. Re:What, are you dense or something? by Anonymous Coward · · Score: 0

      Calling other races "monkeys" and "apes" with the intention of making them look worse than they are, is that funny?

    2. Re:What, are you dense or something? by Anonymous Coward · · Score: 0
      Calling other races "monkeys" and "apes" with the intention of making them look worse than they are, is that funny?

      Your implication that there are certain races that are worse than others makes me weep. A strong onion will do that to me too, though.

    3. Re:What, are you dense or something? by Anonymous Coward · · Score: 0

      If it looks like it was my implication, it's probably because english isn't my first language, and so I suck horribly at it.

  58. READ THIS ON HOW YOU SHOULD MOD PARENT by Anonymous Coward · · Score: 0

    Taken from I'm a racist.'s journal:

    I'll have to do a bit of karma-whoring on a regular basis, just to keep my default post score above 0. If you're a racist, and a moderator, feel free to throw me some points, just to keep my posts visible.

    Please consider your moderations carefully.

    1. Re:READ THIS ON HOW YOU SHOULD MOD PARENT by VanillaCoke420 · · Score: 0, Offtopic

      Exactly. He also said it's weird that we shouldn't judge other on racial basis, since we can judge people on their friendliness, intelligence, etc. What he fails to understand is that race is not the same as the other things we sometimes judge people from. There are friendly and unfriendly people among all races, and stupid and smart people among all races. To judge on the basis of race would have interesting implications, since I am pretty sure he is white, and I am white, and I know a lot of white people that all are different. How can he expect me to judge all these people in the same way simply because all these people are white?

  59. Why? by amoups · · Score: 1, Insightful

    The post is relevant and unoffensive. You take offense to his username and profile. I don't like his opinions any more than you, perhaps, but I'm not wasting today's precious mod points on someone's lifestyle choice. What if his u/n was I'm a Queer?

    --
    Society doesn't turn on a dime, but if enough people lean on the steering wheel long enough, it can negotiate a curve.
    1. Re:Why? by Anonymous Coward · · Score: 0

      When was the last time you heard about queers going around killing people because they were straight?

    2. Re:Why? by Anonymous Coward · · Score: 0

      Being a "queer" doesn't involve the hurtful actions that being a racist typically involves, espically in this case.

    3. Re:Why? by amoups · · Score: 1

      So we automatically assume I'm_a_racist is a violent person just because of his beliefs? Not all anti-abortionists are murdering doctors, and not all racists are members of the KKK.

      --
      Society doesn't turn on a dime, but if enough people lean on the steering wheel long enough, it can negotiate a curve.
    4. Re:Why? by Anonymous Coward · · Score: 0
      Being a "queer" doesn't involve the hurtful actions that being a racist typically involves

      What? A racist calls you names, and doesn't invite you to dinner. A queer sticks things up your ass!

      I report, you decide.

  60. How dissapointing by Anonymous Coward · · Score: 0, Funny

    Is there anyone else out there who read the title and was let down by the fact that this had nothing to do with pornography?...

  61. The imag is not blurred; thats whats interesting! by Beautyon · · Score: 2, Interesting

    The most intersting thing about these images now is the fact that they are not blurred:

    This Nature article describes how....hmmm I had better quote:

    "As a beam of starlight hops towards us through countless Planck times, its speed varies. This would smear the beam out so that different parts arrive at different times and distort our picture of where it came from. The longer the journey, the bigger the smear."

    So that means that these deep Hubble photographs should all get more blurry the deeper you look and not razor sharp like we have come to love.

    Its a fascinating problem!

    --
    ATH0 Bitcoin: 1DnwFLXczVZV8kLJbMYoheUrpqHesjxrSi
  62. Hey Autopr0n by rat7307 · · Score: 1

    Hey pr0n,

    Looks like your site has some opposition!!!!

    Props to you, dude!!

    --
    Burma?
  63. Re:The imag is not blurred; thats whats interestin by TMB · · Score: 2, Informative

    I've read that paper, and there's a major problem - they do the calculation in the direction of propogation, but then try to use the result in the transverse direction. You can't do that. No one's done the calculation in the transverse direction, so we still don't know what the theoretical prediction should be.

    [TMB]

  64. How many stars are in the "visible" sky? by ortholattice · · Score: 2, Interesting
    The article says 300,000 stars were captured in 3.1 arcminutes. Let's see, assuming uniform distribution of them:

    a = angle subtended by capture (radians) = 2*pi*3.1/(360*60) = .000901
    b = area of capture on a sphere of radius 1 =approx= a^2 = .0000008118
    c = fraction of entire sphere = b/(4*pi) = .0000000646
    d = number of visible stars in entire sky = 300000/c = 4,643,000,000,000

    So that means almost 5 trillion stars are visible by Hubble in the entire sky. That's a lot of stars to catalog. (Assuming I didn't err like they did in the $97 trillion RIAA calculation... someone pls double check and flame me if appropriate.)

    1. Re:How many stars are in the "visible" sky? by LMCBoy · · Score: 2, Interesting

      Afraid I don't quite agree with your detective work, there :)

      Your mistake is the assumption that this image is representative of the entire sky's stellar density. HST was pointed near the Andromeda Galaxy for this image; almost all of the stars you are seeing are in the Andromeda Galaxy. Most points on the sky will have a much lower density of stars. See, for example, the Hubble Deep Field, which was purposely pointed at an "empty" region of sky, and which contains only a handful of stars.

      --
      Liberal (adj.): Free from bigotry; open to progress; tolerant of others.
    2. Re:How many stars are in the "visible" sky? by kindbud · · Score: 2, Interesting

      They pointed the HST at an area of sky 1 degree southwest of the Andromeda galaxy, M31. They wanted to take a census of stars in the halo of M31. So the number of faint stars/sq.arc.min. in this region of the sky is likely to be higher than in other areas. Even though the Milky Way also has an halo of stars that extends in all directions, and so faint stars would be expected to be seen by Hubble if it pointed in any direction, M31's halo of stars would be concentrated in the area of M31 and cause a local abundance in its vicinity.

      --
      Edith Keeler Must Die
    3. Re:How many stars are in the "visible" sky? by falzer · · Score: 1

      It also contains a handful of galaxies. :-)

  65. deep photo by Perdition · · Score: 1

    But it kinda looks like that second spheroid nebula from the left had his eyes closed...

    --
    Windows XP SP2 told me to install third-party software that prevents viruses and protects stability... I chose Ubuntu
  66. YHBT. by Anonymous Coward · · Score: 0

    YHL. HAND.

  67. Re:So awesome it's theological. by Anonymous Coward · · Score: 0

    Where were you when I laid the earth's foundation?
    Tell me, if you understand.
    Who marked off its dimensions? Surely you know!
    Who stretched a measuring line across it?
    On what were its footings set,
    or who laid its cornerstone--
    while the morning stars sang together
    and all the angels shouted for joy?

    --Job 38:4-7

  68. helps to be a professional astronomer... by supernova87a · · Score: 4, Interesting

    Ok, here's the calculation for you curious types, regarding how many photons arrived from the faintest star in the picture:

    Let's suppose that the picture was taken in the "V" filter. I just happen to have the number of photons per second per meter squared that arrive from a star of 20th magnitude: 86.157. (taken from here ).

    So the faintest stars in this picture are 31st magnitude? That's 11 mags fainter than 20, which by the handy old formula

    mag1-mag2 = -2.5 * log(flux1/flux2)

    which means that the 30th magnitude star puts out about 4x10^(-5) times as much flux.

    Using the reference star's flux from above, this means that 0.0034299 photons per second per meter squared arrived at Hubble. The exposure was 84 hours, and the area of Hubble is (2.5m)^2*pi, so tada:

    The total number of photons in the picture from the faintest star is: 20365.83

    Still not too shabby. They probably could have found even fainter stuff.

  69. Realtive Deepness by HerbieStone · · Score: 1
    So this is a little off-topic. But got me thinking of a childs joke-question. Here it goes:

    Q: How deep would a bunny hop into the woods?
    A: Right into the middle of it, beyond that point he would be hoping out of the woods.

    Have nice day.

  70. GP by dh003i · · Score: 1

    I hadn't bothered to look for the latest figures.

    Of course, my statement was oversimplistic. If we survie another 1 billion years, then the furthest object we'd be able to resolve would be 14.5-15 billion light years away.

    Anyways, the article on parallel universes is very interesting. Somewhere out there, there's a universe where I'm dictator of the world! ;-)

  71. Re:The imag is not blurred; thats whats interestin by FrostedWheat · · Score: 1

    Wouldn't that simply cause 'Temporal Blur' .. so that if something was moving it would appear blurred. Most of what we see is moving so slow (from our point of view) that it may as well be static - so we'd never notice a bit of temporal smear.

    *shrugs*

    NOTE: I don't know what I'm talking about :)

  72. Gratuitious "lightbulb joke".. by GroundWire · · Score: 1

    How many astronomers does it take to take a digital picture of the sky? ......

  73. Re:helps to be a professional troll... by Anonymous Coward · · Score: 0

    A professional astronomer plugging the *diameter* of a circle into A=pi*r^2? Give me a break.

  74. Correction by fmaxwell · · Score: 1

    The next image of that section of sky is unlikely to be taken by a scope with diffraction spikes rotated relative to the former.

    Oops! I meant to say "likely" rather than "unlikely." Sorry for any confusion that may have caused.

  75. Re:helps to be a professional troll... by supernova87a · · Score: 1

    point taken. Divide the final number by 4!

  76. Re:This is the first? Can't be! by Anonymous Coward · · Score: 0

    Nah, that photo only goes as far as Uranus.

  77. Re:The imag is not blurred; thats whats interestin by dillon_rinker · · Score: 1

    Dimes will get you dollars that the "theoretical prediction" is EXACTLY what we're seeing. Otherwise, it's not much of a theory, is it, and there's not much mileage in telling your thesis advisors that they've been smoking crack for twenty years.

    "But wait!" you say. "Perhaps the graduate student in question would come up with a NEW and IMPROVED theory!" Right. In which case, her "theoretical prediction" would be EXACTLY what we're seeing, right? =)

  78. Magnification? by Anonymous Coward · · Score: 0

    What was the magnifacation factor of the photo? In other words, was it 1,000 times, 10,000, etc.. I've looked and looked for this, but I can't find a single reference to that. Is that type of info classified?

    1. Re:Magnification? by Anonymous Coward · · Score: 0

      Have you *ever* seen the magnification factors on Hubble quoted? There's a reason for that. You shouldn't even ask for such information.

    2. Re:Magnification? by Liquid+Tip · · Score: 1

      If you want a magnification (although the concept is misleading for these type of images) the HST ACS field of view is 202x202 arcsec (where 3600 arcsec = 1 degree). Now measure the *angular size* of the pic on your monitor (for easy comparision your fist at arms length is about 10 degrees). Comparing the two numbers gives you a "magnification".

    3. Re:Magnification? by Anonymous Coward · · Score: 0

      That information is classified. Even though the Hubble telescope can not be turned around to spy on the Earth, a future one may be built that can, so the government is very tight-lipped about the abilities of Hubble. You will *never* see that information published. If you do see someone quoting a number, it's just a conjecture.

  79. Die die Nazi scum. by Anonymous Coward · · Score: 0

    You are a racist, bigoted shitmaggot and a disgrace to the whole of the human race. May you get into a car accident and the only way to save your worthless life is by a blood transfusion from a Black man. Preferably a Jewish one.

  80. You'd be wrong. by Anonymous Coward · · Score: 0

    Nope, he's not a "freakwhore". He really is a racist.

    That whole series of irritated replies was a freakish event.

    Down with Saudi Arabia!!!

  81. A photon and the naked eye by mattr · · Score: 1
    Someone above mentioned 31st magnitude is a trillion times dimmer than what the human eye can see. And someone else mentioned that the faintest star in the image was made with about 20,000 photons captured over 3.5 days.

    Something seems strange. I remember hearing that the human eye can discern a single photon, as from radioactive breakdown in a wristwatch face. I found something to back that up here and here (actually apparently single photons are discarded as noise; 2 or three are better).

    So by my calculations, if you pick a 31st magnitude star in the jpeg and look in the right direction for ten seconds, you will probably get a single photon from the star you picked. Of course you'll get lots of other photons too since your eye can only discern an angle of one arc minute and all those stars are in about 3 arcminutes square.

    I just thought it was neat that while obviously the human eye can't beat the HST in most areas it does seem to be about 20,000 times more sensitive than the Hubble's CCDs by those calculations! Anybody know if the CCDs can actually trigger on single photons? What a fantastic picture. I want to pan across it all night.

    1. Re:A photon and the naked eye by Liquid+Tip · · Score: 1

      A CCD is capable of detecting single photons. In fact, the Quantum Efficiency (QE) of CCDs is usually better than 90% for red colours. The human eye is usually quoted to have a QE around 1%. (so if the QE is 1% only 1/100 photons are detected). The key point is to be able to distinguish a photon from a star from "sky" photons (ie. scattered light). If a dim object is placed on a bright background, it is very difficult to detect the dim object. Just compare the night sky with and without a full moon! So the number of photons detected is meaningless without comparison to the noise involved.

  82. Then we're older, right? by DrMorpheus · · Score: 1
    This lets us learn a lot about the ages and chemical composition of M 31's halo stars, which turn out to be quite different from the stars in our halo (our halo is entirely composed of ancient, metal-poor stars; M 31's halo contains stars that are only 6 Gyr old, and much more metal-rich than our halo).
    That would imply that our galaxy is much older than M31. If that's the case then what does this imply about life in the universe? I mean if our galaxy is one of the oldest out there that would imply that life may not have evolved yet in other galaxies. Or is M31 not typical?
    --
    Debunking the "59 Deceits"
    1. Re:Then we're older, right? by LMCBoy · · Score: 1

      Well, not quite. M 31 has stars that are just as old as our oldest stars, it just has the younger stars also in its halo, which we do not have. All of our younger stars (younger than say, 10 Gyr) are in the disk.

      Many galaxy formation models basically assume this fact: that the halo formed first and all at once, and then the gas that would become the disk collapsed down and started forming stars later, and at a more continuous pace. These models will now need to be reconsidered.

      --
      Liberal (adj.): Free from bigotry; open to progress; tolerant of others.
  83. Re:So awesome it's theological. by Anonymous Coward · · Score: 0

    Fuck off, sandal warrier.

  84. @* PORN JOKE *@ by Anonymous Coward · · Score: 0

    I once got root on a server in another country. I found a bunch of porn on it. I downloaded some of it, but due to the slow connection I wasn't able to get much (nevermind the 56k I was connected to my local shell account on, this was 1995 mind you). Then my friend came over, and I showed him that I had cracked root. It was actually the first time I had gotten root. I had run a brute force attack on the password file, and it was successful. I liked to say that I "bruted the root." Anywas, my friend came over, I let him have a go at the pound prompt. What does he do? He types in "rm -rf /" and boom.. there goes my server and all the porn. Bummer.

    Actually, I made up the part about there being porn on the server. I was really just upset that my idiot friend fucked up that server for no good reason. That fucking jackass.

    Incidentally I tried months afterwords and wasn't able to connect to it. I actually don't think anyone ever used that machine in the first place, and probably no one noticed when it was taken out. I could've done so much with it...

  85. But are there Aliens? by 4_Scythe · · Score: 1

    Is it just me, or did almost everyone only look at this picture to see if they could find aliens or an alien planet somewhere?