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(IAAC) OBJECT: M101 (spiral galaxy) INST: 16" f/4.59 dobnewt SKY: suburban LM=5.1z




Observer:  Todd Gross
Your skill:  Intermediate 
Date and UT of observation: 02/07/98 09:30 GMT
Location & latitude: 22 miles west of Boston, Ma. 42.3N
Site classification: Suburban
Limiting magnitude (visual): 5.1 zenith  est, 4.9 in vicinity of object
Seeing (1 to 10 - worst-best):   6
Moon up (phase?): No
Weather: Clear, snowcovered, lots of scattered cirrus clouds
Instrument: 16" Newtonian-dob w. 96/99% coatings f/4.59   f.l. 1865
Magnifications: 124x,44x
Filters used: none
Object: M101 (is also M102)
Constellation: U Ma.
Object data: face-on spiral galaxy
Size(s): Large - 40'
Position: RA 14:03  DEC +54:21
Magnitudes: 7.9
Personal "rating" (at this aperture, and sky condition):  B-/C+

Face-on spiral with low surface brightness. Core was easy as it
gradually brightens as in an unresolved globular. However, even 
with aperture, light pollution and cirrus clouds hampered the view
of the outer structure. Nevertheless, at 44x it appears as a large
oval glow, with a brighter core, and hint at structure.  

Much more structure can be made out at 124x in my light conditions,
but did not want to bring it to more magnification than that since I 
already could not fit the entire galaxy in the field of view. Spiral arms
were noted, by tracing the dark lanes,  but not overwhelming. 
Mottling throughout the arms, with dark lanes curling in towards core, 
best viewed with averted vision. Not nearly at easy to see as M51. 
Also not as impressive in these conditions as M33. (but similar)

Oval knot on the NE side appeared almost like a separate galaxy in 
itself, but I did not see this listed in catalogs. The knot has higher surface
brightness than it's immediate surrounding spiral arm.





- Todd
_________________________________
BOSTON TV METEOROLOGIST TODD GROSS
Weather/Astronomy Home Page: http://www.weatherman.com
Administrator, NE Weather Watcher Mail List, wxobs-sne@shore.net
Originator of the NE.WEATHER newsgroup
_________________________________
Email: toddg@weatherman.com    Work Phone# (617)725-0777