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Hubble Finds Double Einstein Ring

Posted by Soulskill on from the billions-and-billions dept.

Einstein Duble brings us news that astronomers using the Hubble Telescope have discovered an extremely rare double Einstein Ring. Occasionally, galaxies or other bright objects are located in such a way that they are behind another galaxy when viewed from Earth. When light from the further galaxy passes a sufficiently massive closer galaxy, the path of the light is bent inward from all sides, creating a "ring" effect. In this case, not one, but two galaxies are directly behind the foreground galaxy, so the gravitational lens produces two distinct rings. Quoting Presscue: "The distribution of dark matter in the foreground galaxies that is warping space to create the gravitational lens can be precisely mapped. In addition, the geometry of the two Einstein rings allowed the team to measure the mass of the middle galaxy precisely to be a value of 1 billion solar masses. The team reports that this is the first measurement of the mass of a dwarf galaxy at cosmological distance (redshift of z=0.6)."

10 of 168 comments (clear)

  1. Who said Hubble was a waste of money? by mastershake_phd · · Score: 5, Insightful

    This is a prime example of the kind of useful knowledge that can be gained with projects like Hubble.

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    Libertarian Leaning Political Discussion Forum.
    1. Re:Who said Hubble was a waste of money? by pilgrim23 · · Score: 5, Interesting

      Proving Einstein's theory was always been about getting a little behind as it were. The solar eclipse of May 29,1919 was the first confirmation of this. And, this new discovery is much like the 191 observation only writ large, one might say glactic large.

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      - Minutus cantorum, minutus balorum, minutus carborata descendum pantorum.
    2. Re:Who said Hubble was a waste of money? by caramelcarrot · · Score: 5, Insightful

      Given that they are only vastly different scales, it is important - there is still uncertainty as to how gravity acts on extremely large galactic scales.

    3. Re:Who said Hubble was a waste of money? by mastershake_phd · · Score: 5, Insightful

      If you're truly Libertarian, Hubble is exactly the sort of thing you'd be against having the government fund.

      C'mon, homefry. Walk the walk if you're gonna talk the talk.

      Some Libertarians might be against funding things like Hubble. I personally am more concerned with personal freedom, and a balanced budget. Private industry isn't going to do certain things, Hubble is a prime example. The last thing this country needs to do is cut scientific research.

      --
      Libertarian Leaning Political Discussion Forum.
  2. You forgot about time by rewt66 · · Score: 5, Insightful

    These things line up in space-time as follows: Galaxy 1 is on the line 11 billion years ago, galaxy 2 is on the line 6 billion years ago, galaxy 3 is on the line 3 billion years ago, and the Milky Way is on the line right now.

    This does not mean that the reverse is true. It does not mean that there is a line that the Milky Way was on 11 billion years ago, and galaxy 3 was on 8 billion years ago, and galaxy 2 was on 5 billion years ago, and galaxy 3 is on now. Why not? Because galaxies move.

    Still, even if not technically correct, it was a really awesome thought by the OP...

  3. Re:Not as amazing.. by jamesh · · Score: 5, Funny

    You just passed up a golden opportunity to post a goatse link... the universe will never forgive you!

  4. Re:Here come's the PR Blitz by The+Master+Control+P · · Score: 5, Insightful

    Don't worry, we can pay for the whole thing by leaving Iraq one or two days earlier. And plus, if you look at it from the financial angle, a space-industrial complex is just as good of an excuse for corporate welfare handouts as the military-industrial complex. The only difference is that if we spent $300 Billion a year on science, we'd probably get something good for humanity out of it.

    It's sad that spending money to unravel the secrets of the universe is sneered at (see parent) while large numbers of people and entire news networks (not necessarily including parent) champion spending trillions of dollars to keep poking the middle east hornet's nest (And apparently think that if we keep poking, the hornets will get tired and give up).

  5. You forgot about mass too by Loki+P · · Score: 5, Informative

    And the other problem is the masses of all the galaxies are different. The dwarf galaxy wouldn't act as a lens for them in the same way that the massive galaxy does for us.

  6. Re:Precise by GaryPatterson · · Score: 5, Interesting

    There's a great story about the first person to accurately measure the height of Mount Everest, whose name escapes me at the moment.

    His calculations came out to precisely 29,000 feet. Thinking no-one would believe such a round number, he added two feet to make 29,002 feet but was greatly annoyed by the whole thing.

    Later it was more accurately measured at 29,029 feet (going from memory here) using lasers or something.

  7. Re:Which part of the knowledge is useful? by Martian_Kyo · · Score: 5, Insightful

    I am sure some people wondered in 1600s 'why is that newton guy researching gravity he is such a fool, I know if i drop an apple it falls. What does it matter how fast it falls, that won't help my crops grow.'
    There is no useless knowledge. There is knowledge we don't know how to use yet but no useless knowledge. Time will show, determining mass of a galaxy might turn out to be an essential calculation 300 years from now on, given civilization continues to evolve until then.