Astronomy Picture of the Day
Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.
2003 May 5 
Posted on 05/05/2003 1:39:45 AM PDT by petuniasevan
Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.
2003 May 5
Explanation: In NGC 1275, one galaxy is slicing through another. The disk of the dusty spiral galaxy near the image center is cutting through a large elliptical galaxy, visible predominantly on the lower left. Galaxies can change significantly during a collision like this, with gravitational tides distorting each galaxy and gas clouds being compressed and lighting up with new star formation. Galaxy collisions occur in slow motion to the human eye, with a single pass taking as much as 100 million years. NGC 1275 is a member of the Perseus cluster of galaxies that lies about 230 million light years away toward the constellation of Perseus. Each galaxy spans about 50,000 light years across. The above picture is a composite of images taken by the Hubble Space Telescope in 1995 and 2001.
I will be on vacation from June 2nd through June 9th.
If anyone would like to volunteer to post APOD during that time, please FReepmail me.
Otherwise the APOD will not be posted as I will be visiting relatives in California.
Another designation for this galaxy is Perseus A (strongest radio source in Perseus)
Galactic collisions are actually fairly common.
It's easier to see the filaments and faint structures in a photographic negative:
This is a galactic cluster located about 8 billion light-years away. It contains a large number of colliding galaxies.
CATALOG OF SPIRAL GALAXIES SHOWS EVIDENCE OF GALACTIC COLLISIONS
Perseus A
![[NGC 1275 image]](Pics/n1275.jpg)
| Right Ascension | 03 : 19.8 (h:m) |
|---|---|
| Declination | +41 : 31 (deg:m) |
| Distance | 235,000 (kly) |
| Visual brightness | 11.6 (mag) |
| Apparent dimension | 2.6 x 1.9 (arc min) |
'Glad to hear that you're doing well after your oral surgery. I guess one can now say that "the tooth is out there"...
(sorry ;-)
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