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(IAAC) Obj: M110 (companion to M31) - Inst: 8" f/10 SCT, 8x50



Observer: Lew Gramer
Your skills: Intermediate
Date and UT of Observation: 1997-11-29/30, 02:40 UT
Location: Miles Standish State Forest, Carver, MA, USA (41N)
Site classification: rural
Limiting magnitude: 6.6 (zenith), 6.1 (in SE)
Seeing: 2 of 10 - excellent
Moon up: no
Instrument: 8" f/10 Schmidt-Cassegrain on fork equatorial, 8x50mm finder
Magnification: 80x, 170x
Filters used: None
Object: M 110 (companion to M 31)
Category: Elliptical galaxy [E5P]
Constellation: And
Data: mag 8.07  size 22'x11'
RA/DE: 00h40m  +41o41m
Description:
A lovely, elongated thread-spindle of bright gauze met me through
the 80x eyepiece tonight, after I centered my finder on the faint
averted-vision haze NW of the core of huge M31. Probably the most
fascinating thing about this bright little companion in even this
"everyday" aperture, is its remarkable resemblance to a binocular
or finder view of its mighty parent, the Great Andromeda Galaxy.
Like M31, it has a strikingly oblong halo (N-S for M110), which in
turn envelopes an "off-axis" elongated halo (NW-SE for M110). And
like M31, the interface between the very bright core and the only
somewhat fainter halo shows some very intriguing complexities: in
the case of M31 of course, these are the split-off points of its
vast spiral arms, replete with dust lanes and mingled HII regions.
In the case of M110, it is not at all clear what these very real
mottlings correspond to! At any rate, they are much subtler than
in the parent. Finally, to averted vision, the S portion of M110's
halo shows the slightest hint of bending toward M31 below it. This
was best seen at higher power, by moving M31 completely out of the
field. Knowing that the "P" in M110's morphology referred to this
evidence of gravitational interaction, I intentionally looked for
this "S" sweep in its halo: sure enough, it was visible tonight!