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As Hubble Breaks a Distance Record, We Learn Its True Limits

Posted by Soulskill on from the still-can't-find-my-sunglasses dept.

StartsWithABang writes: You might think that, when it comes to finding the most distant objects in the Universe, all we need is a good telescope, to leave the shutter open, and wait. As we accumulate more and more photons, we're bound to find the most distant, faint objects out there. Sure, Hubble just broke its own cosmic distance record, but it's certainly not the most distant. Thinking so misses an important fact: the Universe is expanding! And with that expansion, the wavelength of the light we can see gets redshifted. Ultraviolet light winds up in the infrared, infrared light winds up in the microwave, and the most distant galaxies that are out there are invisible, even to Hubble. Here are Hubble's limits, and how the James Webb Space Telescope will overcome them.

53 comments

  1. Enticing RSS by wonkey_monkey · · Score: 1, Funny

    As often happens, my RSS feed display chopped off the end of the headline, and my overactive imagination supplied a much more interesting conclusion:

    As Hubble Breaks a Distance Record, We Learn Its True ...

    Purpose.

    It's a radio... for talking to God!

    --
    systemd is Roko's Basilisk.
    1. Re:Enticing RSS by Anonymous Coward · · Score: 0

      You are a cow. A cow says moo. MOOOOOO! Moo cow moooooo! COW!

    2. Re:Enticing RSS by Anonymous Coward · · Score: 0

      can we just skip that awful part and go straight to yosemite?

    3. Re:Enticing RSS by Anonymous Coward · · Score: 0

      It's a radio... for talking to God!

      Unfortunately, it's only a radio receiver, for listening to God.

      Maybe there's still time to put a transmitter in the James Webb Space Telescope?

      "Mr. God. Come here. We need you."

    4. Re:Enticing RSS by Headw1nd · · Score: 4, Funny

      Unfortunately for us, the God in question turns out to be Azathoth.

    5. Re:Enticing RSS by AikonMGB · · Score: 1, Funny

      Purpose.

      It's a radio... for talking to God!

      What does God need with a radio?!

    6. Re:Enticing RSS by Anonymous Coward · · Score: 0

      ...or a spaceship?

    7. Re:Enticing RSS by rmdingler · · Score: 1

      Purpose.

      It's a radio... for talking to God!

      What does God need with a radio?!

      Or money, from weekly tithes, for that matter...

      --
      Happiness in intelligent people is the rarest thing I know.

      Ernest Hemingway

    8. Re: Enticing RSS by Anonymous Coward · · Score: 0

      An army that carries this telescope before it... is invincible...

    9. Re: Enticing RSS by rickb928 · · Score: 1

      He doesn't, of course. But the people who gather together and try to talk to him prefer to do it indoors, with the lights on, heat or A/C as appropriate, and sometimes they even pay people to lead these sessions, so they don't have to work at McDonald's to maintain their lives and be somewhat distracted. All that takes money.

      It's really very simple. Just think it through.

      --
      deleting the extra space after periods so i can stay relevant, yeah.
    10. Re: Enticing RSS by wonkey_monkey · · Score: 1

      Because to anyone looking in the other end, they'll seem tiny and far away.

      --
      systemd is Roko's Basilisk.
    11. Re:Enticing RSS by dlingman · · Score: 1

      Because putting fist sized gold nuggets in the flower gardens of the churches hasn't worked out so well.

    12. Re:Enticing RSS by tygreen101 · · Score: 1

      Purpose.

      It's a radio... for talking to God!

      What does God need with a radio?!

      see Ancient Aliens theory...

    13. Re:Enticing RSS by rubycodez · · Score: 1

      hush you, plundering church gardens for those has been working out GREAT for me. what the churchgoers don't know, won't hurt them

    14. Re: Enticing RSS by Anonymous Coward · · Score: 0

      What's the frequency, Kenneth?

  2. Exclamation marks by WinstonWolfIT · · Score: 0

    Any science article that insists on shouting at me... sucks. I HATE HATE HATE this writer.

    1. Re:Exclamation marks by Anonymous Coward · · Score: 1

      Because using capitals to indicate an exclaimation rather than an exclaimation point makes you look more intelligent?

    2. Re:Exclamation marks by lister+king+of+smeg · · Score: 2

      Please quit shooting all caps are worse than of what you are complaining, unless they have four in a row in which case fuck that guy there is never an excuse for four exclamation points

      (briefly skims blogpost)

      nope only one used at a time

      --
      ---Saying gnome 3 is better than windows 8 not so much a compliment as it is damning with light praise.
  3. Stop with the autoplaying videos, Slashdot! by hackertourist · · Score: 0

    What were you thinking, putting an autoplaying video on the front page????

    1. Re:Stop with the autoplaying videos, Slashdot! by cobbaut · · Score: 1

      What were you thinking, putting an autoplaying video on the front page????

      (Sorry for going offtopic)
      Strange that video's never autoplay on my computer. Maybe you should install adblock+, ghostery, muter, ... or something.

      --
      European Linux user, living in Antwerp
    2. Re:Stop with the autoplaying videos, Slashdot! by tehcyder · · Score: 1

      What were you thinking, putting an autoplaying video on the front page????

      (Sorry for going offtopic) Strange that video's never autoplay on my computer. Maybe you should install adblock+, ghostery, muter, ... or something.

      Yes, because everyone reads slashdot on their infinitely customisable home computer, and not at work.

      --
      To have a right to do a thing is not at all the same as to be right in doing it
    3. Re:Stop with the autoplaying videos, Slashdot! by Anonymous Coward · · Score: 0

      I imagine Slashdot's own employees and editors must use adblock to view the site themselves, or they would have long ago noticed that the ads and some of their scripts will bring any machine to a halt. My home machine has adblock, but my workstation at work, which is rather new and a beast of a system, comes to a near stop on Slashdot after a minute or two. Even typing a comment is like working on an old dial up terminal and watching letters appear one a second.

  4. Logical by mwvdlee · · Score: 0

    No offense to the awesomeness that is Hubble, but isn't it logical for it to break distance records on a regular basis as more "old" light reaches it simply as a function of time?

    --
    Slashdot social media options: AIM, ICQ, Yahoo, Jabber and Mobile Text. Why no MySpace?
    1. Re:Logical by Anonymous Coward · · Score: 0

      You're going off an intuition gained from sound: Wait longer and sounds from farther away will arrive.

      Light, in the case of the universe, has already been arriving for 13.7 billion years and waiting a few more means nothing.

      In addition, the expansion of the universe is now accelerating, which actually means that the distance to the visible horizon - the most distant object we can see - isn't growing, it's *shrinking*. As the expansion accelerates, objects nearer and nearer will be moving away from us at faster-than-light speeds and disappear.

      It is not unremarked upon that we are very fortunate to live in an era of the universe when we are capable of seeing all the way back to recombination (before then, the universe was completely filled with white-hot opaque plasma and light couldn't travel). In the distant future, everything except the handful of galaxies in the local group (and cosmic background radiation, stretched to ungodly wavelengths) will have retreated beyond the horizon. How could cosmology ever be developed in that scenario?

    2. Re:Logical by Sique · · Score: 5, Informative

      I guess you stumbled on a logical error (and you didn't read the article). 1. Very old light reaches us all the time, not just since the start of the Hubble. Thus light from very far away objects has hit Hubble from the beginning, but we weren't able yet to identify it. So there is a function of time, but it has more to do with our increasing ability to make sense of Hubble data. 2. The article talks mainly about the limits of Hubble. As it has a limited mirror area, the amount of light it can collect is limited. Objects farther away have to be brighter to be visible with Hubble. 3. Hubble works only with light that can be reflected by its mirror. The longest wavelength it can detect is 1 micron. As light that comes from far away is redshifted, its wavelength increases. Usually we use the Lyman series of absorbtion lines of Hydrogenium to measure the redshift. As soon as the shortest wavelength of the Lyman series is redshifted to a wavelength of more than 1 micron, we can't see it anymore in Hubble. Thus the farthest object of which we can estimate the distance with Hubble can't be farther away than the redshift of the Lyman series to 1 micron allows. Yes, also X ray can be redshifted to UV and to visible light, which then could be detected by Hubble, but we can't measure the redshift (yet), because we don't know how to identify the absorbtion lines that exists in X rays.

      --
      .sig: Sique *sigh*
    3. Re:Logical by SharpFang · · Score: 1

      That's only if our telescopes could reach the Hubble Sphere. That way light speed + space expansion would be our distance limit and only time would allow us to see objects between the Hubble Sphere and the Cosmic Space Horizon.

      But so far with our best equipment we are barely reaching a third of this distance and our limits are still of technological nature - or more accurately of economical nature (we *know* how to build better telescopes that would reach farther, but we don't have the budget).

      --
      45 5F E1 04 22 CA 29 C4 93 3F 95 05 2B 79 2A B2
    4. Re:Logical by SharpFang · · Score: 1

      the distance to the visible horizon - the most distant object we can see - isn't growing, it's *shrinking*.

      Not yet.
      We have a much more firm limit in the form of the image of the Big Bang and it's still within the Hubble Sphere. We technically *could* see past it, but even if we had the hardware, it's pretty much opaque.

      Yes, as the universe ages, the image moves away from us at c + expansion rate, and eventually it will vanish behind the cosmic event horizon forever, and since then its acceleration will begin to swallow objects making less available for observation. But we have a good few billion years until the cosmological limits imposed by space expansion become our worry. Until then, our theoretical limits are caused by the structure of the universe, and practical limits - by $$$.

      --
      45 5F E1 04 22 CA 29 C4 93 3F 95 05 2B 79 2A B2
    5. Re: Logical by Anonymous Coward · · Score: 0

      1 micron is a radio wavelength, not optical. What you say is mostly correct but the units are wrong.

    6. Re: Logical by Anonymous Coward · · Score: 0

      1 micron is pretty solidly in the middle of near infrared, not far from the ~700 nm visible cutoff. Regular optics tend to work pretty well with it, and it is about three orders of magnitude from the typical separation from IR and RF/microwaves.

    7. Re:Logical by TapeCutter · · Score: 1

      We have already seen the point where the universe turns from an opaque plasma soup into transparent space. IIRC that's why the first cosmic background pics were called "the face of god".

      --
      And did you exchange a walk on part in the war for a lead role in a cage? - Pink Floyd.
    8. Re:Logical by Anonymous Coward · · Score: 0

      Okay, this is true - I should've distinguished between the realistic limit (surface of last scattering/CMB) and the relativistic causal limit that contracts/stays/expands depending on acceleration.

      Come to think of it, I've never actually bothered to even ballpark calculate how long until the CMB vanishes under lambda-CDM... heh.

    9. Re:Logical by gumbi+west · · Score: 1

      What's absorbing in the x-ray region? Certainly not hydrogen, taking a 1s to free would not absorb that much energy.

    10. Re:Logical by Anonymous Coward · · Score: 0

      Plenty of heavier elements have x-ray absorption and transmission lines, usually involving the excitation of an inner electron. And heck, the Lyman series is on the verge of x-rays with just hydrogen, and wavelength would scale like 1/Z^2 for hydrogen-like ions, although you don't need nearly fully stripped ions to get x-ray transitions.

      Although I don't know what the GP is talking about not being able to identify x-ray absorption lines. X-ray lines, absorption and emission, are used in lab plasma experiments all the time. The issue isn't identifying lines, but gathering enough light. The further something is away, the dimmer it is, even when the FLRW metric causes the angular size to not shrink with distance any more.

  5. Yawn, linkspam, yawn by Anonymous Coward · · Score: 0

    Lame hipster website still unreadable. Spammer still spammy. Just the headline stinks enough to keep me well away.

    Shit guy, what is it with you and clickbait tripe in would-be-scientist-sauce? You got no life or something?

  6. So launch it already! by Anonymous Coward · · Score: 0

    Honestly, I've lost count of how many articles I've seen promoting the JWST. How many years ago did they have that big pavilion at SXSW? How badly over budget and late is it to need this much PR for this long in order not to get the axe?

    Well, maybe the funding pressure will be going down since the GOP is killing off the Earth-facing stuff.

  7. The scale is backwards by towermac · · Score: 1

    Note TFA has a redshift(z) scale that is backwards. They have z=1 at 6 billion years, and z>20 at 200 million years.

    1. Re:The scale is backwards by necro81 · · Score: 1

      Note TFA has a redshift(z) scale that is backwards. They have z=1 at 6 billion years, and z>20 at 200 million years.

      I puzzled over that for a moment, too. What the time scale shows is age of the universe, or (as the scale is labeled) years since the Big Bang. So z>20 = universe at 200 million years old, not years ago. It's confounding and, to my eyes, counterintuitive, but perhaps that's how cosmologists work.

    2. Re:The scale is backwards by PaulMattSutter · · Score: 2

      Yes, this is how we work :)

      I've heard it joked that this is the difference between astronomers and physicists. Astronomers put the observer at the 0-point of the coordinate system, hence larger redshifts are further away. On the other hand, physicists put the 0-point at the "beginning" of the universe: the initial conditions, and mark time after that.

    3. Re:The scale is backwards by Anonymous Coward · · Score: 0

      God, this is Y2K writ large! In a few billion years, the fragmentation will become intolerable!

  8. an important fact! by Guildor · · Score: 2, Insightful

    "an important fact: the Universe is expanding!" : Actually, this is not known, only theorized. It's based on the notion that red-shift / blue-shift relate to distance. But that's never been proven, and there are others out there that think it isn't about motion at all. Although we have a consensus opinion that uses it as fact, it isn't a proven fact.

    1. Re:an important fact! by cyn1c77 · · Score: 1

      "an important fact: the Universe is expanding!" : Actually, this is not known, only theorized. It's based on the notion that red-shift / blue-shift relate to distance. But that's never been proven, and there are others out there that think it isn't about motion at all. Although we have a consensus opinion that uses it as fact, it isn't a proven fact.

      Why is the parent modded down when the post is correct and politely stated?

      In my opinion, this is one of the biggest secrets (hidden in plain sight) present in astronomy today. It's highly relevant to every article about space outside our galaxy yet I have never seen an unbiased article in layman's terms discussing the implications of the ubiquitus redshift-distance relation being wrong.

      Maybe we have too many professional astronomers with mod points?

    2. Re:an important fact! by Anonymous Coward · · Score: 4, Informative

      Why is the parent modded down when the post is correct and politely stated?

      The GP, at this time, is not modded down. The GP has a history of down modded posts causing bad karma and a low score on new posts.

      And looking at the GP's history, this seems to be one of the few times where the post mentions red shift in open-endedly, instead of proposing the idea that red shift is caused by different star ages, something that runs completely against basic physics of how red shift works in both observation and the lab.

      It's highly relevant to every article about space outside our galaxy

      Red shift is not the only distance measure outside of our galaxy. Stories, even on Slashdot, have discussed subtle changes to those other distance measurements and the impact it has on Hubble's law. And while it is relevant to every article, shouldn't be expected to be in every such article, just as not every article that mentions Newtonian mechanics isn't going to discuss the limitations of using an approximation to relativity.

      Maybe we have too many professional astronomers with mod points?

      Considering how often the first people to post something using large words around here get modded up, even if failing at intro level astronomy stuff, or how people get modded up for dismissing astronomy theories with no actual basis or content in their post, I don't think it is astronomers with mod points we have to worry about.

    3. Re:an important fact! by Anonymous Coward · · Score: 0

      . But that's never been proven, and there are others out there that think it isn't about motion at all

      The only two known ways to produce a consistent, wavelength independent red shift are through motion and general relativity effects, both of which are part of the currently accepted theory of the red shift vs. distance relationship.

    4. Re:an important fact! by lister+king+of+smeg · · Score: 1

      . But that's never been proven, and there are others out there that think it isn't about motion at all

      The only two known ways to produce a consistent, wavelength independent red shift are through motion and general relativity effects, both of which are part of the currently accepted theory of the red shift vs. distance relationship.

      Or we could have areas of space with greater for lack of a better term "density of volume" where a given space is bigger on the inside than it would appear from out.
      http://arxiv.org/abs/1308.6731
      (yes the scientist who purposed it called tardis space)

      --
      ---Saying gnome 3 is better than windows 8 not so much a compliment as it is damning with light praise.
    5. Re:an important fact! by Anonymous Coward · · Score: 0

      That isn't an "Or... " at least in the usual xor interpretation or "or" in English. The redshift in the paper is still due to general relativity, not contradicting the previous post that said redshift is due to motion or GR. In particular, the paper is just an interesting variation on the Sachs-Wolfe effect already used in interpreting the CMB.

  9. Emphasize the security aspect by tepples · · Score: 1, Insightful

    Then maybe you should promote these extensions to work's IT department as security tools, citing the use of Flash ads as drive-by Trojan droppers.

  10. CSI to the rescue by edxwelch · · Score: 1

    Maybe they should ask CSI for some help. Those guys have tech that can magnify any image to infinity.

    1. Re:CSI to the rescue by Anonymous Coward · · Score: 0

      It's called "super-resolution" in real life.

  11. StartsWithABang gets an editor? by jeffb+(2.718) · · Score: 1

    Wow. Instead of StartsWithABang's usual EndsEveryOtherSentenceWithABang, it's down to EndsEveryThirdParagraphWithABang. Progress!