ASTRO: M105 and friends

Very good detail in the small galaxy (NGC 3373). And, as you said, the
colour contrast is striking.

Stefan

"Rick Johnson" schrieb im Newsbeitrag
ster.com...
Still not an Arp galaxy but it is a galaxy.

M105 is a large elliptical galaxy in Leo. It is part of the Leo I group
which includes M95 and M96 which is located about 40 million lightyears
away. M105 is the large spherical (E0) galaxy. It is also known as NGC
3379. To the NE is NGC 3384/3371 (SB0), also a member of the group.
It's another of those galaxies with two NGC numbers. NGC 3384 better
fits its position in the sky so is considered the main designation of
the two. Below it is NGC 3389 (SAc) a very blue spiral galaxy. It's
redshift puts it at a distance nearly twice as far away as the Leo I
group. Thus it is more likely a member of the nearby Virgo Cluster.
The color contrast between a spiral that is currently forming new stars
and the reddish hue of elliptical galaxies that haven't had much if any
star formation for billions of years is quite striking.

Some of the galaxies in the background are part of the Zwicky galaxy
cluster 1045.8+1251. It is listed as 45 minutes in diameter (larger
than my long diameter of 33 minutes) and to contain 120 galaxies. He
listed it as "medium distant" the second closest class out of 5. How
these distances were determined I don't know. Red shift was not used.
One paper says his near and medium distant classes are quite accurate
when compared to red shift data but the other classes tend to
overestimate their distance.

The image contains 4 asteroids. Easiest to find northwest (right) of
M105 is (50572) 2000 EM39 at magnitude 17.3 East of NGC 3384 near the
left edge of the image is (49344) 1998 WC4 at magnitude 19.0. Two
others near 20th magnitude are in the image but difficult to find so I
won't point them out. The Minor Planet Center is now tracking over
440,000 known asteroids. It's no wonder they keep showing up in my
images!

The image also contains galaxies beyond the Zwicky cluster as well as a
few quasars. I've included an annotated image pointing these out along
with their distance in billions of light years. Galaxies are labeled
with a G in front of their distance. Quasars have no label, just their
distance. Note one galaxy, nearly 3 billion light years away, can be
seen right through NGC 3384 showing how little dust and gas galaxies of
this type have and thus, why star formation ceased long ago.

A photo of this area taken by the 0.9 meter telescope on Kitt Peak is at:
http://www.noao.edu/image_gallery/images/d5/m105.jpg

You can read more about M105 at:
http://seds.org/messier/m/m105.html

14" LX200R @ f/10, L=4x10' RGB=2x10', STL-11000XM, Paramount ME

Rick
--
Correct domain name is arvig and it is net not com. Prefix is correct.
Third character is a zero rather than a capital "Oh".