Re: Tonight's APOD photo
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Re: Tonight's APOD photo
Can anyone explain to me why stars A, B and C - and the bright object near the supernova look much brighter in the left, or before, photo? I would have thought they'd need to be exposed at the same level to get a true comparison.
A Totally Uneducated Observer Who Still Gets Curious
A Totally Uneducated Observer Who Still Gets Curious
"When I am old, I shall wear" - Nothing, of course!
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SN 2005ap (APOD 16 Oct 2007)
Could anyone enlighten me as to exactly where this supernova emmanated from? You know, like in or near what constellation?
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SN2005ap (APOD 16 Oct 2007)
In the "before" image, a little past half way toward the bright star to the left of the letter A, you see a blotch of light that is not present in the "after" image. Instead, there appears to be a streak, perhaps a tail, going directly toward the supernova. I wonder if SM2005ap is in fact visible in both images. It would be interesting to see images taken prior to the "before" and following the "after" images.
Isaiah 40:26
Re: SN 2005ap
In Coma Berenices, according to the press release.
R.A. = 13h01m14.84s, Dec. = +27°43'31.4" (or R.A. = 195.31183°, Dec. = 27.72539°)
to be precise...
SDSS color image ("before") with noise reduction.
R.A. = 13h01m14.84s, Dec. = +27°43'31.4" (or R.A. = 195.31183°, Dec. = 27.72539°)
to be precise...
![Smile :)](./images/smilies/icon_smile.gif)
SDSS color image ("before") with noise reduction.
Re: Tonight's APOD photo
The photo on the left is from the Sloan Digital Sky Survey, based in New Mexico, the one on the right is from the Hobby-Eberly Telescope, based in Texas. Different telescopes, different locations, different weather - no wonder there are slight differences in the photos.trucker743 wrote:why [do they] look much brighter in the left photo?
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Looks Like C and D Dimmed and A Brightened
I am not sure this is not a novae rather than Supernovae.
Look at C and D dimming with A brightening. Why Supernovae versus novae.
Has this been seen by many observatories?
SN 1987 A certainly was, but has this been observed multiple times.
I learned this summer how our constitution is about the right of judges to threaten jail when you express concern with rights. I did not know that. They helped me understand the American Legal System.
Look at C and D dimming with A brightening. Why Supernovae versus novae.
Has this been seen by many observatories?
SN 1987 A certainly was, but has this been observed multiple times.
I learned this summer how our constitution is about the right of judges to threaten jail when you express concern with rights. I did not know that. They helped me understand the American Legal System.
James T. Struck
is it a matter of luck or ....
Is it a matter of luck there is a " before " image at the exact spot this thing blew up ? Were there hints there was going gto be an event ?
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Re: is it a matter of luck or ....
There have been many photographic all sky surveys. For the most part, there are images of the entire sky available, so there are "before" images whenever a supernova happens.ta152h0 wrote:Is it a matter of luck there is a " before " image at the exact spot this thing blew up ? Were there hints there was going gto be an event ?
Where luck comes in is the rare case where a supernova area gets imaged just before the event is detected, such that the early stages are caught. That's not the case here.
Chris
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Thanks!
Makes perfect sense! Thanks - Hope I wasn't a bother!
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The blotch is there, but dimmer, apparently another star. If you compare all the stars in the before and after, you will notice the after image is dimmer. I don't know what the perceived tail is, but my best guess is a compression artifact or random noise. I'm not sure whether that background fuzz is noise or fainter stars.
The star that caused SN2005ap would not have been visible before the supernova. Assuming the red-shift distance method is correct, it's 5 billion light years away. Individual stars become impossible to distinguish with our best telescopes at distances even a small fraction of that (some where on the order of 100,000 LY, I think). Even a long Hubble exposure would have only faintly showed the galaxy the source star resides in. In fact, it seems this single star briefly outshone its entire parent galaxy.
The star that caused SN2005ap would not have been visible before the supernova. Assuming the red-shift distance method is correct, it's 5 billion light years away. Individual stars become impossible to distinguish with our best telescopes at distances even a small fraction of that (some where on the order of 100,000 LY, I think). Even a long Hubble exposure would have only faintly showed the galaxy the source star resides in. In fact, it seems this single star briefly outshone its entire parent galaxy.
"Any man whose errors take ten years to correct is quite a man." ~J. Robert Oppenheimer (speaking about Albert Einstein)
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Images from same Telescope would help
Several of us have observed differences between Hobbel Ebberly and SDSS besides the alleged Supernovae.
It might be good if the Michigan Technical University or other NASA staff involved in Astronomy picutre of the day posted a before and after image from
SDSS
Before and After or now
Hobbell Eberly
Before and After Now
Just to study consistency in photos and differences between telescopes and observations. This is helpful conversation for me. All I meant is I learned about governments violating rights more; I was not as aware in a personal way of that even though I should have understood that better.
James T. Struck
It might be good if the Michigan Technical University or other NASA staff involved in Astronomy picutre of the day posted a before and after image from
SDSS
Before and After or now
Hobbell Eberly
Before and After Now
Just to study consistency in photos and differences between telescopes and observations. This is helpful conversation for me. All I meant is I learned about governments violating rights more; I was not as aware in a personal way of that even though I should have understood that better.
James T. Struck
James T. Struck
Re: Images from same Telescope would help
The problem is that supernovas fade pretty quickly; fading from view over several weeks or months. A SN from 2005 at 4.7 billion light-years would now be as invisible as before discovery. Archive photos are all we have.TimeTravel123456789 wrote:It might be good if they posted a before and after image from the same telescope
I doubt your comparison-curiosity will be enough for precious telescope time, at a piece of the sky where there is nothing to see.