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Astronomy Picture of the Day -- Circling a Black Hole at its Photon Sphere
NASA ^ | July 02, 2013 | (see photo credit)

Posted on 07/03/2013 5:34:55 PM PDT by SunkenCiv

Explanation: What would it look like to go right up to a black hole? One particularly interesting place near a black hole is its photon sphere, where photons can orbit in circles, a sphere 50 percent further out than the event horizon. Were you to look out from the photon sphere of a black hole, half of the sky would appear completely black, half of the sky would appear unusually bright, and the back of your head would appear across the middle. The above computer-animated video depicts this view from the photon sphere. The reason that the lower region, as shown, appears black is because all light paths from this dark region comes up from the black hole -- which classically emits no light. The upper half of the sky now appears unusually bright, blueshifted, and shows increasingly many complete sky images increasingly close to the dark-light divide across the middle. That dark-light divide is the photon sphere -- your location -- and since photons can do circles there, light from the back of your head can circle the black hole and come to your eye. No place on the sky is hidden from you -- stars that would normally pass behind the black hole now appear to zip quickly around an Einstein ring, a ring that appears above as a horizontal line about a quarter of the way down from the video top. The above video is part of a sequence of videos visually exploring the space near a black hole's event horizon. (Disclosure: Video creator Robert Nemiroff is an editor for APOD.)

July 02, 2013

(Excerpt) Read more at 129.164.179.22 ...


TOPICS: Astronomy; Astronomy Picture of the Day; Science
KEYWORDS: apod; astronomy; blackhole; science
[Credit & Copyright: Robert Nemiroff (MTU)]

1 posted on 07/03/2013 5:34:55 PM PDT by SunkenCiv
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To: brytlea; cripplecreek; decimon; bigheadfred; KoRn; Grammy; married21; steelyourfaith; Mmogamer; ...
(Disclosure: Video creator Robert Nemiroff is an editor for APOD.)
Sorry I was late posting this.

2 posted on 07/03/2013 5:35:46 PM PDT by SunkenCiv (McCain or Romney would have been worse, if you're a dumb ass.)
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To: SunkenCiv

And here I am still trying to wrap my head around the explanation of the event horizon and the last block hole video...................


3 posted on 07/03/2013 6:20:25 PM PDT by doorgunner69
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To: SunkenCiv

This is making me dizzy!


4 posted on 07/03/2013 8:22:27 PM PDT by Sarajevo (Don't think for a minute that this excuse for a President has America's best interest in mind.)
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