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Hubble Finds Double Einstein Ring
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)."
This is a prime example of the kind of useful knowledge that can be gained with projects like Hubble.
Libertarian Leaning Political Discussion Forum.
One of the cool implications becomes clear if you realize this means our galaxy is the 4th galaxy in a line with these three. To someone standing on a planet in that backmost galaxy, 11B Ly away: ...
* 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!
I stole this sig from someone cleverer than me.
And (s)he's got a really big ruler!
Engineering is the art of compromise.
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...
As the double ring they found around Uranus
788652 = 2 x 2 x 3 x 3 x 19 x 1153
I was afraid it was a trick to make me click on a link to goatse.cx guy.
That upgrade is on hold. The problems that knocked the latest Atlantis mission back into February have jacked up the schedule. So it was planned for August but now it will be later. I would think that with eol for the shuttle and hubble both rapidly approaching - any more problems or serious delays and it could get knocked from on hold to canceled.
It's hard to believe that's how Micronians are made. Why don't we see it right now by having you both kiss one another?
Brannigan: "What the hell is that thing?"
Kif: "It appears to be the mothership"
Brannigan: "Then what did we just blow up?"
Kif: "The Hubble Telescope"
I'm going to go create my own technology news site, with blackjack and hookers. You know what? Forget the news site.
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).
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.
Layne
Another article on this double ring find.
Additionally, the astronomers' significant others are annoyed at them for ruining the coffee table by not putting Eincoasters under their Einsteins.
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.
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.
"The distribution of dark matter in the foreground galaxies that is warping space to create the gravitational lens can be precisely mapped." Really? How can we "precisely map" something that we have never even shown positively to exist yet? The distribution of gravity could be caused my a number of things other than "dark matter". Gravitational disturbance by itself is not evidence for dark matter, any more than it supports at least several other hypotheses.
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, 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."
The measured mass of a galaxy useful? On its own, maybe or maybe not. Yet through this fortunate alignment we were given the chance to get information that, for lack of a better word, helps us 'calibrate' our astronomical tools.
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?
Out of modpoints but really liked a post? 1BDkF6TtmmeZ3yqXbz9yhdYVqRYnwFoXDj
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.