NGC 2355 (Lund 311, Cr 133) Open cluster in Gemini

Located at: RA 07 hours 17 minutes 00 seconds, Dec +13 degrees 45 minutes 00 seconds

Size: 9.0' (8.0') Magnitude: 9.7 Class: II 2 m

North is up

West to the right

Telescope:

 14.5" f5 Newtonian reflector

Camera:

  ST-8XME, self-guided, binned 1x1, temp -15c, camera control MaxIm DL 4.56

Image:

Lumicon Red filter, 200 minutes (20 x 10 minute subs), 04/3/2015; seeing 2.7-5.0 FWHM per CCDStack

Processing:

CCDStack 2.89.5560.25580, Photoshop CS5.1

Location:

 Rolling Roof Observatory, Thousand Oaks, CA 91360 (+34d 13m 29s -118h 52m 20s)

Notes: I had wanted to start imaging a galaxy rising in the north (keeping away from the full moon), but my neighbor's patio lights were on, and shined into my tube (creating an unacceptable gradient). So I tried imaging a one night object that was away from the moon. NGC 2355 was already past the meridian, so I had to image low in the west (last sub seeing was ~5 arc seconds). See the 8" image.

According to "Star Clusters", by Brent Archinal and Steven Hynes, the size of this open cluster is 8.0 arc minutes.

From the NGC / IC Project:

Contemporary Visual Observation(s) for NGC 2355

NGC 2355 = Cr 133 = Mel 63 = OCL-496 = N2356?
07 16 59 +13 45.0
Size 9

13.1": about 50 stars down to mag 14 in a 8'x5' group elongated N-S including a 
mag 10 star at the SE edge.  Rich, fairly compact, a number of stars are 
arranged in lanes.  Located about 7' SW of mag 8.0 SAO 95722.

- by Steve Gottlieb
Historical Research Notes / Correction for NGC 2355
NGC 2356 is most likely NGC 2355 with a 10 arcmin error in declination.  There
is no other group of stars in the area that fits WH's description "A pretty
rich and compressed cluster of stars" as well.  JH did not see NGC 2356, but
found NGC 2355 easily.  Note, too, that WH's position for N2355 is about 1m
40s too far west; Dreyer discusses the circumstances of WH's observation of
N2355 a bit more in his 1912 edition of WH's papers. - Dr. Harold G. Corwin, Jr.