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(IAAC) Obj: M34 - Inst: 8" f/10 SCT
Observer: Lew Gramer
Your skills: Intermediate
Date and UT of Observation: 1997-11-03/04, 02:50 UT
Location: Medford, MA, USA (42N)
Site classification: urban
Limiting magnitude: 5.1 (zenith), 4.4 (in S)
Seeing: 5 of 10 - mediocre
Moon up: no
Instrument: 8" f/10 SCT, 8x50mm finder
Magnification: 80x, 170x, 340x
Filters used: None
Object: M34
Category: Open cluster
Constellation: Per
Data: mag 5.2 size 35'
RA/DE: 02h42m +42o47m
Description:
The "Spiral Cluster" (from Jeff Bondono, for its shape) was a quick
find at the W apex of an equilateral triangle with kappa and beta
Per (Algol). This open cluster was readily visible as a brightish,
irregular haze in the 8x50 finder, with two medium-bright stars
immediately resolved to SE and NNW of center, and 2 or 3 more of
various brightnesses then becoming visible with concentration. In
the 8" SCT, the OC easily fills the 25mm (80x, 35') field of view,
with outliers spilling out as much as a 40' radius to the W and NW,
and a few stragglers to SE. At the core are perhaps 40 members in
a 20' diameter, with many brighter members (mag 7-9) and perhaps
20 members on the edge of visibility (mag 13-14), but few stars
of intermediate brightness. Out to 60' diameter, perhaps 90 total
members can be counted, with a much more even magnitude distrib-
ution and fewer bright stars than the core. Interestingly, many
stars near the center of this cluster have a strange tendency to
form into similar-magnitude pairs, including pairs of magnitudes
7, 7, 8, 8, and 9. Finally, at PA 60o 25' from center is a pretty
contrasting double (mag 7, 9.5; PA 310o; gold and pale violet).