OR 12/28/13: Resolving the Brightest Star in M33
by Steve Gottlieb
On December 28, 2013 (Saturday) I met Carter Scholz at Lake Sonoma during an unusual stretch of clear, dry winter weather. There were two other participants, Matt Marcus and Caroline Scolari. The transparency was predicted by the CSC to be excellent as well as no cloud cover, though the jet stream was running right down the coast, so seeing was expected to be poor. But the seeing was fine, especially for the first several hours, though I often kept to 260x. Observing started close to 6:40 and I stopped a little before 1:00, so there was a good 6 hours to explore a number of lesser known targets and some eye-candy. I ended up logging about 50 objects and some of the highlights are below. Steve Gottlieb |
M33-B324 B324, a highly luminous hypergiant, is the brightest individual star in M33. It appeared as a mag 15 star at the north edge of |
This trio consists of the 8' physical pair NGC 672 and IC 1727, which reside at a distance of ~25 million l.y., along with NGC 684 (up to 10x the distance). IC 1727 = KTG 8A
appeared fairly faint, very large, very elongated 3:1 NW-SE, low surface brightness, ~2.5'x0.8' though the outer halo fades into the background gradually so the dimensions are
difficult to estimate. Contains a slightly brighter "bar" that is extended 4:1 or 5:1 NW-SE, ~45"x10". The halo is more extensive NW of this bar, so the appearance is asymmetric.
NGC 672 = KTG 8B lies 8' NE and appeared very bright, very large, elongated 5:2 WSW-ENE, mottled appearance. Contains a brighter, elongated "bar" that is slightly angled (roughly
7:2 E-W) to the major axis of the halo. Slightly brighter "patches" were visible just beyond the bar (on both the east and west side), probably where spiral arms attach to the bar.
NGC 684, another 34' NE, appeared as a fairly bright, beautiful edge-on 7:1 E-W, 1.8'x0.25', sharply concentrated with a very small, very bright core and a faint stellar
nucleus. |
At 375x, IC 161 = VV 54a appeared moderately bright, fairly small, elongated 3:2 ~E-W, 0.4'x0.25', well concentrated with a very bright core than increases to a stellar nucleus.
An extremely faint companion off the SE side (the pair forming |
KTS 15 = ESO 543-021/-022/-023 KTS 15, a trio of ESO galaxies in Cetus, consists of a close pair and a thin edge-on ~14' SE. |
KTS 28 = NGC 1721/1725/1728 KTS 28 consists of three prominent NGC galaxies forming an E-W chain. |
UGCA 128 = KTS 32A dominates this trio as a moderately bright and large glow, round, irregular surface brightness, 1.0' diameter, contains a bright 20" core. Several stars are
involved or nearby including a mag 12.5 star off the NW end, 1.4' from center and a mag 13 star at the SSE side, 40" from center. In addition a mag 15 star is at the north edge,
along with another mag 15 star right at the NW end. |
At 200x, |
NGC 7674, the brightest member of |
Using 200x and an OIII filter, this small Abell planetary appeared fairly faint, round, 0.4' diameter, crisp-edged and uniform surface brightness. Better view unfiltered at 375x,
as the disc appeared to have a slightly irregular surface brightness (though not clearly annular). Abell 4 lies just 38' ESE of the center of |
NGC 1530 in Camelopardalis is fairly bright, large, elongated nearly 3:2 N-S, ~3.5'x2.2'. Contains a large, brighter circular core within a very large, elongated halo. A low contrast, thin spiral arm is attached on the west side of the core and sweeps north at the edge of the halo and a similar enhancement is visible on the east side extending due south. Two mag 15 stars [22" separation] are superimposed on the NW side [1.1' from center] and a mag 12.8 star lies 2.5' N. |
NGC 2146, the "Dusty Hand", is a highly distorted (post-merger?) galaxy, with a dusty spiral arm that has looped in front of the galaxy's core. NGC 2146 appeared very bright, very large, elongated 5:2 NW-SE, ~5'x2', with a very asymmetric structure. Contains a very bright, elongated core, ~1.2'x0.5' NW-SE, but with no distinct nucleus. A low contrast dust lane cuts through the core unevenly, with the main section on the north side, so the lane initially appears to run parallel to the core on the southwest side. But a fainter, elongated section of the core extending NW-SE is just beyond the dust lane on the southwest side. To the southeast of the core, the outer halo is diffuse with a low surface brightness and is not aligned with the major axis of the core, extending more towards the east. On the NW side of the core, the halo has a higher and irregular surface brightness with a slightly brighter curving arc (arm) along its eastern side. |