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Hubble Finds Double Einstein Ring
Posted by
Soulskill
on Thu Jan 10, 2008 08:00 PM
from the billions-and-billions dept.
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)."
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Submission: Hubble finds double Einstein ring by Anonymous Coward
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Who said Hubble was a waste of money? (Score:5, Insightful)
Re:Who said Hubble was a waste of money? (Score:5, Interesting)
Parent
Re:Who said Hubble was a waste of money? (Score:5, Insightful)
Parent
Re:Who said Hubble was a waste of money? (Score:4, Insightful)
C'mon, homefry. Walk the walk if you're gonna talk the talk.
Parent
Re:Who said Hubble was a waste of money? (Score:5, Insightful)
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.
Parent
Re: (Score:3, Interesting)
Personal freedom, sound economic policy, measured intervention in things that won't look after themselves - isn't this what we used to call 'Liberalism'? All the Libertarians I have encountered labour under the delusion that they are universal experts and that nobody but them (least of all people with actual domain-specific training!) should be doing any resource allocation. They don't want to fund street repairs - in case someone else uses tarmac they helped pay for - let alone science. Certainly a total f
Re: (Score:3, Interesting)
Ha-ha... Those are universal values. The political distinction depends on what you call "personal freedom", what is sound economic policy, how you measure the intervention, and which things you identify as incapable of "looking after themselves".
"Liberalism" in America tends to consider free health care (at someone else's expense) an inalienable right,
Re:I agree, but... (Score:4, Insightful)
Layne
Parent
Re: (Score:2)
Re:Who said Hubble was a waste of money? (Score:5, Insightful)
Seriously, I hate this sort of thing. Any proposal has good and bad sides. When you're making a decision you count them and weigh them against eachother. Then you make a decision. Obviously, he values 'really free market' really highly, but that doesn't mean he's not allowed to acknowledge the cases when there are more cons to his approach than usual.
Acknowledging arguments and still making a decision is a sign of intelligence. Trying to force somebody else to make false choices, or attributing false opinions to them is stupid.. and way too bloody common.
Parent
Which part of the knowledge is useful? (Score:3, Interesting)
Re:Which part of the knowledge is useful? (Score:4, Insightful)
The universe is understood by using phenomenae like this to test our theories and provide a sort of astronomical 'yard stick' by which we can measure other objects. Objects that without this yard stick would be less well understood. One discovery is built upon another until, one by one, they form the sum of our understanding.
So why not go out and measure the mass of that little rock in your backyard? Wouldn't it be amazing to discover that it had a density of 19.3 g/mL?
Parent
Re:Which part of the knowledge is useful? (Score:5, Insightful)
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.
Parent
And to them, we are the ring (Score:4, Interesting)
* The one that's the "foreground galaxy" to us would be the inner ring.
* The one that's the "first ring" to us would be the foreground galaxy for them and
* The Milky Way would appear as the outer ring!
Re:And to them, we are the ring (Score:5, Insightful)
* The one that's the "foreground galaxy" to us would be the inner ring.
* The one that's the "first ring" to us would be the foreground galaxy for them and
* The Milky Way would appear as the outer ring!
Actually, that's not the case. I'll give you a hint. The reason is because of something the guy these rings are named after, figured out. These galaxies aren't aligned. They just look that way from our perspective. From the other direction, it's extremely unlikely these 4 galaxies ever aligned, as odd as that sounds.
Parent
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Re: (Score:2, Insightful)
of the light will be exactly the same since the path is dictated by the perturbation of spacetime.
You forgot about time (Score:5, Insightful)
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...
Parent
You forgot about mass too (Score:5, Informative)
Parent
Re: (Score:2, Funny)
The communications delay is gonna make online gaming with those guys a bit cumbersome.
Re:You forgot about time (Score:4, Insightful)
We are at "hypothetical centre of the big bang", as is everything else.
Parent
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If the galaxies look aligned from our perspective, they will look aligned from theirs. The inverse path
of the light will be exactly the same since the path is dictated by the perturbation of spacetime.
I fail to see how this might be modded Troll. As for the statement, however, it doesn't work both ways - An Einstein Ring or Einstein Cross is not a discreet feature in space, it's an event similar in principle as an eclipse or occultation, and just as ephemeral
Re: (Score:3, Interesting)
So... there is a God (Score:4, Funny)
Parent
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Extemely Rare? (Score:3, Insightful)
Not as amazing.. (Score:4, Funny)
Re:Not as amazing.. (Score:5, Funny)
Parent
Whew! (Score:4, Funny)
Would you please take the ECW off the SciFi Chan.. (Score:2)
Halo? (Score:2)
Obligatory Futurama (Score:3, Funny)
Kif: "It appears to be the mothership"
Brannigan: "Then what did we just blow up?"
Kif: "The Hubble Telescope"
non-slashdotted hubble double ring article(w/pics) (Score:5, Informative)
Einstein comment (Score:2)
Ba dum bum (Score:5, Funny)
Apologies to Macbeth (Score:5, Funny)
Bubble, bubble, toil and trouble
Hubble finds an Einstein double
Give a shivering man a lit match and it will warm him for a few minutes.
Set him on fire and it will keep him warm for the rest of his life.
Duble? (Score:2)
odds of this (Score:3, Insightful)
Re: (Score:2)
Propaganda (Score:2)
Re:Propaganda (Score:4, Informative)
Yes it is kind of like propaganda to assume dark matter theory is right, but that's the best theory there is. "Dark matter" is just a name for "whatever causes these observations." Whatever it is looks and acts like a gravitational field. Mass produces a gravitational field, so it's assumed to there's some sort of invisible mass, some sort of "dark matter." And they can still "precisely map" the gravitational field, regardless of what is causing it.
And unless you know something physicists don't know, there's not a "number of things" that could cause a gravitational field like that. Interestingly, there is another theory, ether theory [nationalgeographic.com], but even the physicist who came up with it says: "We're offering an alternative to the dark matter theory--we're not saying it's wrong. If I had to bet today on which of these theories was correct, I might bet on dark matter."
Parent
Re: (Score:3, Insightful)
They're called 'airplanes' and we even have a place to park them called 'airports'
Re:Yay Hubble (Score:5, Informative)
Parent
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Re:Precise (Score:5, Interesting)
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.
Parent
Re: (Score:2, Informative)
Re: (Score:2, Funny)
Re:Here come's the PR Blitz (Score:5, Insightful)
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).
Parent
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Re: (Score:3, Informative)