NGC 206 is a bright
star cloud in the
Andromeda Galaxy
The Andromeda Galaxy (IPA: ), also known as Messier 31, M31, or NGC 224 and originally the Andromeda Nebula, is a barred spiral galaxy with the diameter of about approximately from Earth and the nearest large galaxy to the Milky Way. The gala ...
. It is notable for being the brightest star cloud in Andromeda as viewed from
Earth
Earth is the third planet from the Sun and the only astronomical object known to harbor life. While large volumes of water can be found throughout the Solar System, only Earth sustains liquid surface water. About 71% of Earth's surfa ...
.
Features
NGC 206 is the richest and most conspicuous star cloud in the Andromeda Galaxy as well as one of the largest and brightest star formation regions of the
Local Group
The Local Group is the galaxy group that includes the Milky Way.
It has a total diameter of roughly , and a total mass of the order of .
It consists of two collections of galaxies in a "dumbbell" shape: the Milky Way and its satellites form ...
.
[
] It contains more than 300 stars brighter than M
b=−3.6. It was originally identified by
Edwin Hubble
Edwin Powell Hubble (November 20, 1889 – September 28, 1953) was an Americans, American astronomer. He played a crucial role in establishing the fields of extragalactic astronomy and observational cosmology.
Hubble proved that many objects ...
as a star cluster but today, due to its size, it is classified as an
OB association
In astronomy, stellar kinematics is the observational study or measurement of the kinematics or motions of stars through space.
Stellar kinematics encompasses the measurement of stellar velocities in the Milky Way and its satellites as well as t ...
.
NGC 206 is located in a
spiral arm
Spiral galaxies form a class of galaxy originally described by Edwin Hubble in his 1936 work ''The Realm of the Nebulae''[neutral hydrogen
The hydrogen line, 21 centimeter line, or H I line is the electromagnetic radiation spectral line that is created by a change in the energy state of neutral hydrogen atoms. This electromagnetic radiation has a precise frequency of , w ...]
and has a double structure, with one region that has an age of around 10 million years and includes several
H II region
An H II region or HII region is a region of interstellar atomic hydrogen that is ionized. It is typically in a molecular cloud of partially ionized gas in which star formation has recently taken place, with a size ranging from one to hundreds ...
s in one of its borders and other with an age of between 40 million years and 50 million years that includes a number of
cepheids
A Cepheid variable () is a type of star that Instability strip, pulsates radially, varying in both diameter and temperature and producing changes in brightness with a well-defined stable frequency, period and amplitude.
A strong direct period-l ...
. Both parts are separated by a band of
interstellar dust
Cosmic dust, also called extraterrestrial dust, star dust or space dust, is dust which exists in outer space, or has fallen on Earth. Most cosmic dust particles measure between a few molecules and 0.1 mm (100 micrometers). Larger particles are c ...
and include hundreds of stars of
spectral type
In astronomy, stellar classification is the classification of stars based on their stellar spectrum, spectral characteristics. Electromagnetic radiation from the star is analyzed by splitting it with a Prism (optics), prism or diffraction grati ...
O and
B.
[
]
See also
*
List of Andromeda's satellite galaxies
The Andromeda Galaxy (M31) has satellite galaxies just like the Milky Way. Orbiting M31 are at least 13 dwarf galaxies: the brightest and largest is M110, which can be seen with a basic telescope. The second-brightest and closest one to M31 is ...
References
External links
NGC 206 @ SEDS NGC objects pages*
*
{{DEFAULTSORT:NGC 0206
Star clouds
Andromeda Galaxy
Andromeda (constellation)
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