Author Topic: Possible strong gravitational lenses  (Read 563036 times)

Alice

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Re: Possible strong gravitational lenses
« Reply #15 on: September 15, 2007, 03:25:57 pm »
Welcome back Fluffy, we've been wondering where you've gone. The "Galaxyzooitis!" thread in the Cafe is probably the best bet at present! Ouch, our disease is spreading across the Universe!

fluffyporcupine

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Re: Possible strong gravitational lenses
« Reply #16 on: September 15, 2007, 03:28:05 pm »
thanks alice! got distracted by teh lovely sunshine :o and an air display (which was awsome!!!) and the qualifying and the rugby ( :'( ) and going out later.....naughty fluffy for neglecting the zoo!!! ;D

altymczuk

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Re: Possible strong gravitational lenses
« Reply #17 on: September 15, 2007, 03:40:12 pm »
Isn't this thread supposed to be about "Possible Strong Gravitational Lenses"??  When did the disconnect occur?
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Alice

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Re: Possible strong gravitational lenses
« Reply #18 on: September 15, 2007, 03:41:17 pm »
Sorry! I consider myself to have had a smacked hand.

Beezlebub

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Re: Possible strong gravitational lenses
« Reply #19 on: September 15, 2007, 03:53:48 pm »

587729651810697226


Zoomed out view.
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person can do if they do not care who gets credit for it."

Hanny

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Re: Possible strong gravitational lenses
« Reply #20 on: September 15, 2007, 03:54:09 pm »
sorry, offtopic also, but, yeah! Fluffy is back! ;D

pluk

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Re: Possible strong gravitational lenses
« Reply #21 on: September 15, 2007, 04:27:51 pm »
The second looks possible, but I don't see the expected distortions.

What would those be?
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Tony F

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Re: Possible strong gravitational lenses
« Reply #22 on: September 15, 2007, 07:48:55 pm »

altymczuk

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Re: Possible strong gravitational lenses
« Reply #23 on: September 15, 2007, 11:30:31 pm »
The second looks possible, but I don't see the expected distortions.

What would those be?

A 'smearing' along an arc of the radius. Stronger as the focusing mass gets stronger/higher and the focused objects are farther from the 'lens'.  In the classical example the focused become arc like about the center of the focusing object. See:
http://imagine.gsfc.nasa.gov/docs/features/news/grav_lens.html
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pluk

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Re: Possible strong gravitational lenses
« Reply #24 on: September 16, 2007, 08:14:54 am »
The second looks possible, but I don't see the expected distortions.

What would those be?

A 'smearing' along an arc of the radius. Stronger as the focusing mass gets stronger/higher and the focused objects are farther from the 'lens'.  In the classical example the focused become arc like about the center of the focusing object. See:
http://imagine.gsfc.nasa.gov/docs/features/news/grav_lens.html

Your discreption fits the tuesday 11th september object of the day: (which was also the onset of this topic)


The 8 o'clock arc.
588290880028999911

This is a strong gravitational lens. The red elliptical is a massive galaxy that is lensing a much more distant galaxy (a so-called Lyman Break Galaxy) at a redshift of z=2.73. The strong lensing effect distorts this galaxy, but it also magnifies it, which means it is much brighter than it would be without the lens. That makes it possible to get good spectra of it and so allows us to really study very distant galaxies in the early universe. Strong lenses like this are rare and extremely valuable.

For the so inclined, the paper is here:
http://xxx.lanl.gov/abs/astro-ph/0611138

And to my laymans eye ElisabethB's second image and the one I posted earlier have similar characteristics...

probably not, but ...
588017704546468073

Note the faint ring of blue beads along the bottom-right edge of the elliptical in the center.
Ref: 587732589572325457


So what are those missing that rules out gravitational lensing?
« Last Edit: September 16, 2007, 08:17:33 am by pluk »
We tend to overestimate the effect of a technology in the short run and underestimate the effect in the long run. - Roy Amara, engineer, futurist (b. 1925)

gumbosea

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Re: Possible strong gravitational lenses
« Reply #25 on: September 16, 2007, 08:44:20 am »
587742567317897416
Note blue arc to south; arc radius doesn't seem to intersect galaxy core?? :-\

fluffyporcupine

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Re: Possible strong gravitational lenses
« Reply #26 on: September 16, 2007, 01:49:53 pm »

fluffyporcupine

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Re: Possible strong gravitational lenses
« Reply #27 on: September 16, 2007, 02:34:59 pm »

fluffyporcupine

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Re: Possible strong gravitational lenses
« Reply #28 on: September 16, 2007, 04:02:43 pm »
wasnt my target, but saw if off to one side

588017605222793376

Alice

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Re: Possible strong gravitational lenses
« Reply #29 on: September 16, 2007, 04:22:01 pm »
Wow, that's a cool one.