Hercules Cluster (Abell 2151)
|Deep Sky Object in Summer
|Date & Time: ||Jan 30 2004, from 28:12 to 28:32 JST(+0900)
|Composed 3 shots with 8 minutes exposed|
|Optical: ||Meade 25cm(10") Schmidt-Cassegrain with conversion lens (f=1600mm, F6.3)
|Auto-guided with Meade LX200 Equatorial & Pictor 201XT
|Digital Camera: ||Fujifilm FinePix S2 Pro
|Location: ||Ooizumi vil., Yamanashi pref.
|Camera Settings: ||Recording Format...12bit CCD-RAW, converted to 16bit TIFF(3024×2016)|
|CCD Sensitivity...ISO1600, White Balance...Auto|
The Hercules cluster is positioned near a border to Serpent Caput, contains a little less than 100 member galaxies in span of about 1 degree.
The cluster is off about 3 degrees northeast from gamma Ser.
Individual galaxy has a size of 1 or 2 arc minutes and dimmer than 14 th magnitude, large-ranged scopes can aid you to appreciate several members with your own eyes somehow.
And the cluster has been estimated about 460 millions light years away.
|Abell 2151 / Galaxy Cluster, type 2 1 III|
|R.A.||16h 05m (rough position)|
|Dec.||+17° 44' (rough position)|
|Apparent Size||about 60'|
|# of Galaxies||87|
|Distance||460 million light yrs.|
|Supergalactic cluster||Hercules Supercluster|
Numbers with 4 digits represent NGC #