(IAAC) Obj: M103 - Inst: Newt 4.2" f/4.25

Observer: Lew Gramer
Your skills: Intermediate
Date and UT of Observation: 1996-11-12, 05:10 UT
Location: Medford, MA, USA (42N)
Site classification: urban
Limiting magnitude: 5.4
Seeing: 1 - excellent
Moon up: no
Instrument: Newt Reflector 4.2" f/4.25 (AstroScan)
Magnification: 20x, 65x
Filters used: None
Object: M103
Category: Open Cluster
Constellation: Cas
Data: mag 7.4?  size 6' (catalog) 10' (observed)
RA/DE: 1h33m  +60o42m
Searching the area of this cluster showed a poorly
defined field containing some 18 stars to mag 11.5
within a 10' diameter. There's a big brightness range
in the M103 field, so it makes an intriguing albeit
elusive view in these conditions. The central area of
the cluster contains a pretty "corona" or cup asterism
opening W, with the brightest star of the cluster on
its N lip, and the second brightest (mag 7.5?) at the
bottom of the bowl. About 20' ENE of the corona lies an
association of 4 stars of mag 8-9, and 3 or 4 others mags
11 and above, with still more mag 8-12 outliers merging
into the Milky Way background to the E and N.
Karen Simmons & Lew Gramer dedalus@alum.mit.edu http://www.tiac.net/users/lewkaren