Caption: "This detailed image of the
Andromeda Galaxy (M31, NGC 224)
was taken at the
National Science Foundation's (NSF)
0.9-meter telescope
at
Kitt Peak National Observatory
(which is on Kitt Peak)
with the NOAO Mosaic
CCD camera."
(Slightly edited.)
Features:
- The Andromeda Galaxy
is located in the
constellation
Andromeda.
- It is a large spiral galaxy
rather similar to our own Milky Way (AKA the Galaxy).
- Distance:
0.778(33) Mpc (2.54(11) Mly).
- Size scale: ∼ 70 kpc (∼ 220 kly).
- Apparent size: 3.167° X 1°. This is really very large.
Recall the
Moon's
angular diameter
is 0.5178° ≅
(see Cox-16,303,305;
Wikipedia: Moon:
Appearance from Earth).
The area shown in this image is quite large on the
sky since
the length scale is ∼ 6 times
that of the
full moon.
- "This true-color image
was created by combining images taken in
7 filters:
the UBVRI filters:
main bands ultraviolet, blue, green, red, infrared,
Hα (narrow red),
oxygen [O III] (narrow green)."
(Somewhat edited.)
- The Andromeda Galaxy
M31 is visible
to the
naked eye
as a cloudy star under dark sky
conditions.
It also just appears as a cloudy star in small
telescopes.
What one sees essentially is the
bright central
galactic bulge.
The spiral arms
are relatively faint and can only be seen by high sensitivity imaging
or in visual astronomy
with a large
primary
(i.e., ∼ 2 m in diameter).
- Note that most of the star-like
astronomical objects
seen in this image
are foreground stars in the
Milky Way.
There are two dwarf galaxies
satellite galaxies
of the Andromeda Galaxy
and there may be some
globular clusters
in the Andromeda Galaxy.
- The Andromeda Galaxy is
in Local Group of galaxies
and is the nearest large galaxy to the
Milky Way.
It is approaching us at 266 km/s and will collide and merge with
with the
Milky Way
on the time scale of a few
gigayears (Gyr):
see the
Andromeda-Milky Way collision
video in
galaxy videos
below
(local link /
general link: galaxy_videos.html):
php require("/home/jeffery/public_html/astro/galaxies/galaxy_videos.html");?>
Credit/Permission: ©
T.A.Rector, B.A.Wolpa, NOAO/AURA/NSF,
NOAO /
AURA /
NSF,
before or circa 2003 /
NOAO/AURA Image Library Conditions of Use.
Image link: NOAO Images:
The Andromeda Galaxy.
Local file: local link: galaxy_andromeda_m31.html.
File: Galaxies file:
galaxy_andromeda_m31.html.