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(IAAC) Obj: M76 (Little Dumbbell) - Inst: Newt 20" f/5



Observer: Lew Gramer
Your skills (Beginner, Intermediate, Advanced): Intermediate
Date and UT of Observation: 1997-1-10/11, 03:30 UT
Location: Topsfield, MA, USA (44N)
Site classification (urban, suburban, rural): semirural
Limiting magnitude: 5.9
Seeing: 2 - good
Moon up: no
Instrument: Newt Reflector 20" f/5 (dob)
Magnification: 70x, 210x, 360x (all Nagler designs)
Filters used: None, OIII
Object: M76 (Little Dumbbell)
Category: Planetary nebula
Constellation: Per
Data: mag 12.2  size 65" (halo: 5')
RA/DE: 1h42m  +51o34m
Description:
This planetary is easily found from Theta Per using a wide-field
eyepiece, presenting its beautiful, bright two-lobed shape very
clearly at 70x. Higher power (210x) shows some fainter areas of
nebulosity at each end, forming the classic shape from photos.
At 210x and 360x, the WNW is noticeably the brighter of the two
lobes, and also more smoothly sperical than its counterpart to S.
The ESE lobe is a little less than 0.5 mag dimmer in surface
brightness, with the strong impression of a peaked "anvil" shape
pointing NE on its long axis. With an OIII filter at the higher
magnifications, still more nebulosity is apparent on both sides,
and especially beyond and S of the fainter ENE lobe, apparently
also streaming off (into outer halo?) from the central region.
The central "connecting" region is often missed for some reason,
but on this night was clearly defined between the lobes.
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Karen Simmons & Lew Gramer dedalus@alum.mit.edu http://www.tiac.net/users/lewkaren
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