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The
Horsehead Nebula (also known as
Barnard 33
in emission nebula IC 434)
is a dark nebula in the constellation Orion[1]. The nebula
is located just to the south of the star
Alnitak,
which is furthest east on Orion's Belt, and is part of the
much larger Orion Molecular Cloud Complex. The
Horsehead Nebula
is approximately 1500 light years from Earth. It is one of
the most identifiable nebulae because of the shape of its
swirling cloud of dark dust and gases, which is similar to
that of a horse's head when viewed from Earth. The shape was
first noticed in 1888 by Williamina Fleming on photographic
plate B2312 taken at the Harvard College Observatory
The
red glow originates from hydrogen gas predominantly behind
the nebula, ionized by the nearby bright star
Sigma Orionis.
The darkness of the Horsehead is caused mostly by thick
dust, although the lower part of the Horsehead's neck casts
a shadow to the left. Streams of gas leaving the nebula are
funneled by a strong magnetic field. Bright spots in the
Horsehead Nebula's
base are young stars just in the process of forming
The
above text is taken from
Wikipedia.
The
Orion Nebula (also known as
Messier 42,
M42, or
NGC 1976) is
a diffuse nebula situated south[b] of Orion's Belt. It is
one of the brightest nebulae, and is visible to the naked
eye in the night sky.
M42
is located at a distance of 1,344 ± 20 light years[2][5] and
is the closest region of massive star formation to Earth.
The M42 nebula is estimated to be 24 light years across.
Older texts frequently referred to the
Orion Nebula
as the Great Nebula in Orion or the Great Orion Nebula.
The
Orion Nebula is one of the most
scrutinized and photographed objects in the night sky, and
is among the most intensely studied celestial features.[6]
The nebula has revealed much about the process of how stars
and planetary systems are formed from collapsing clouds of
gas and dust. Astronomers have directly observed
protoplanetary disks, brown dwarfs, intense and turbulent
motions of the gas, and the photo-ionizing effects of
massive nearby stars in the nebula. There are also
supersonic "bullets" of gas piercing the dense hydrogen
clouds of the Orion Nebula.
Each bullet is ten times the diameter of Pluto's orbit and
tipped with iron atoms glowing bright blue. They were
probably formed one thousand years ago from an unknown
violent event
The
above text is taken from
Wikipedia.
This
image is plagued with problems. In order to get good
integration time I had to use all images, also those with
fairly severe star trailing. I had to apply a fair amount of
noise reduction in order to bring out the faint stuff and I
had problems with the colour balancing (there is no real
black point present). Compared with other images on the net
my image is a little bit too orange, but this is the best I
managed to do, without destroying the blues.
An
enlarged (50% of original) can be viewed
here.
The
following software has been used. MaximDL (image
acquisition and guiding), CCDStack (calibration and de-convolution),
PixInsight (cropping, background correction, colour
corrections) and Photoshop CS5 (all the rest, incl Noel
Carbonis Astronomy Tools).
This
image was processed in January 2011
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