NGC 637
Encyclopedia
NGC 637 is an open cluster
of stars in the
constellation
Cassiopeia
. It has a Trumpler classification of I2m and an angular diameter
of 4.2′. At a distance of approximately 7,045 light years, this corresponds to a diameter of 9.8 ly. The estimated age of this cluster is 5–15 million years.
Open cluster
An open cluster is a group of up to a few thousand stars that were formed from the same giant molecular cloud and have roughly the same age. More than 1,100 open clusters have been discovered within the Milky Way Galaxy, and many more are thought to exist...
of stars in the
constellation
Constellation
In modern astronomy, a constellation is an internationally defined area of the celestial sphere. These areas are grouped around asterisms, patterns formed by prominent stars within apparent proximity to one another on Earth's night sky....
Cassiopeia
Cassiopeia (constellation)
Cassiopeia is a constellation in the northern sky, named after the vain queen Cassiopeia in Greek mythology, who boasted about her unrivalled beauty. Cassiopea was one of the 48 constellations listed by the 2nd century Greek astronomer Ptolemy, and it remains one of the 88 modern constellations today...
. It has a Trumpler classification of I2m and an angular diameter
Angular diameter
The angular diameter or apparent size of an object as seen from a given position is the “visual diameter” of the object measured as an angle. In the vision sciences it is called the visual angle. The visual diameter is the diameter of the perspective projection of the object on a plane through its...
of 4.2′. At a distance of approximately 7,045 light years, this corresponds to a diameter of 9.8 ly. The estimated age of this cluster is 5–15 million years.