NGC 129

Also Known as:

Object Type: Open Cluster

Constellation: Cassiopeia

Distance from Earth: 5,450 light years

Apparent Magnitude: 6.5

Coordinates: RA 00H 30M 00S DEC 60 deg 13 min 06 sec

Actual Size: 33.3 light years

Apparent Dimensions: 21 arc-minutes

Discovered by: NGC 129 was discovered by William Herschel in 1788.

Description: NGC 129 is an open cluster in the constellation Cassiopeia.
NGC 129 contains several giant stars.
The brightest member of the cluster is DL Cassiopeiae, a binary system which contains a Cepheid variable.
One more cepheid variable, V379 Cas, is also a possible member of NGC 129.
NGC 129 lies in an area packed with open clusters.
It is estimated to be 76 million years old. There are in total some 500+ open clusters that you can see on the northern hemisphere, that are above 0 degrees declination.
About 100 of these open clusters can be found in an area that runs from the Southeast of Cepheus to the East towards the double cluster in Perseus.
This medium sized open cluster lies in a region with many fieldstars, so it is hard to detect the borders of this open cluster. NGC 129 is not really detached from its background.
This area is called the Cassiopeia Window, because of the great transparency in this direction of the milky way. It is relatively dust-free.
You can look right through our local arm, the Orion Spur, through the inter-arm gap towards the Perseus arm.
That is why we can see so many open clusters in Cassiopeia.
NGC 129 is situated in the inter-arm gap.

Click Below Image(s) for Full Size:

NGC 129 is situated close to the northern celestial pole and, as such, it is visible for most part of the year from the northern hemisphere.
It is located almost exactly halfway between the bright stars Caph (β Cassiopeiae) and γ Cassiopeiae.
It is large but not dense and can be observed by binoculars, through which the most obvious component is a small triangle of stars of magnitude 8 and 9, located in the center of the cluster.
NGC 129 is best viewed late fall through winter.

Platesolve

NGC 129 Open Cluster

Imaging Details
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