[barx1963 (Malcolm)]

Observations 30/01/11

NGC 1807 and 1817 Open Clusters in Taurus
NGC 1807 RA 05 10 46.0 Dec +16 31 00 Mag 7.0 Diam’ 12 No of Stars 37 Brightest Star Mag 9.0 Type cl
NGC 1817 RA 05 12 27.0 Dec +16 41 00 Mag 7.7 Diam’ 20 No of Stars 283 Brightest Star Mag 9.0 Type cl

Locate Pi Orionis (N star of Orion’s shield) move about 3 or 4deg to N to a wide trapezium of bright stars. 3 stars lie in a wide obtuse triangle 3deg just N of f. Both target lie just to N of f star. NGC 1817 is f member of pair. NGC 1817 contains 5 brighter stars located on p side of group which form a tiny asterism reminiscent of the main stars in Delphinus. The f side is a large array of fainter stars, at 115x around 2 or 3 dozen stars are resolved but hundreds more are suggested.
NGC 1807 lies 10’ to p. Has a NS line of 4/5 bright stars, maybe another 4 or 5 stars are resolved. Noticably smaller than NGC 1817, both fit in FOV at 67x.

NGC 2423 Open Cluster in Canis Major
RA 07 35 07.0 Dec -13 52 00 Mag 6.7 Diam’ 12 No of Stars 86 Brightest Star Mag 9.0 Type cl

Sits 30’ to N of M47 (naked eye cluster). Fairly large, fills 50% of field at 67x. Rich in bright stars, appears to have a “bridge” of stars running towards M47.

NGC 2818 Planetary Nebula and Open Cluster in Pyxis
PN RA 09 16 01.5 Dec -36 37 37 Diam” 93 Mag(P) 13.0 Mag(V) 11.6 Mag Cent Star 19.5
OC RA 09 16 10.0 Dec -36 37 00 Mag 8.2 Diam’ 8 No of Stars 298 Brightest Star Mag 11.3 Type clpn

Locate Psi Velorum. A line of bright stars lies about 4deg to Nf which is about 2deg wide. S star of this line is k Velorum. Target lies 50’ to N of this star. Largish cluster of many faint stars. The Plantary Neb is very clear at 115x. PN is round a fairly diffuse with no central star visible. OIII shows very clearly. Very strong resemblance to M46 is noted.

Post observation notes. Not surprisingly searches of the internet do show some confusion as to the nature of this object. The AAO image here http://www.aao.gov.au/images/captions/aat080.html states it is both an OC and PN but the DSS image here at the NGC/IC project indicates it is only the PN. Object originally discovered by Dunlop as number 564.

Observations 02/02/11

NGC 2158 Open Cluster in Gemini
RA 06 07 26.0 Dec +24 05 48 Mag 8.6 Diam’ 5 No of Stars 973 Brightest Star Mag 15.0 Type cl

Locate Propus (Eta Geminorum) and 1 Geminorum by naked eye. Move 1.5deg to Nf from 1 Gem to find glow of M35 in finder. Move back 20’ towards I gem. Very faint glow is detected in eyepiece at 67x. Just resolved 3 or 4 stars at 115x.

NGC 2129 Open Cluster in Gemini
RA 06 01 06.0 Dec +23 19 24 Mag 6.7 Diam’ 6 No of Stars 73 Brightest Star Mag 10.0 Type cl

Lies 50’ to p of 1 Geminorum. Small with 3 bright stars that may be foreground objects. No obvious central concentration.

Observations 06/02/11

NGC 2232 Open Cluster in Monoceros
RA 06 28 02.0 Dec -04 51 00 Mag 4.2 Diam’ 45 No of Stars 20 Brightest Star Mag 5.0 Type cl

Fairly large and sparse, maybe 15 to 20 stars visible. Brightest star estimated at mag 5. Seems to form a shape of an acute triangle running NS.

NGC 2219 Open Cluster in Monoceros
RA 06 23 42.0 Dec -04 41 00 Mag Not given Diam’ 10 No of Stars 25 Brightest Star Mag 7.3 Type cl

Lies 1 deg to p of NGC 2232. Has a pair of stars (maybe foreground?) mag 6.5 and 7 on p and f edges (p star is the brighter). Remainder of stars very faint and not easily seen.

NGC 2184 Open Cluster in Orion
RA 06 11 41.0 Dec -03 36 00 Mag Not given Diam’ 33 No of Stars 30 Brightest Star Mag 9.0 Type cl?

Consists of 25 to 30 stars of about mag 9 in a 30’ wide field. A mag 5.5 star lies on p side. Wide and sparse but a very pretty Open Cluster

Observations 08/02/11

NGC 2301 Open Cluster in Monoceros
RA 06 51 46.0 Dec +00 28 00 Mag 6.0 Diam’ 15 No of Stars 80 Brightest Star Mag 8.0 Type cl

Locate Delta Monocerotis. A distinct “house” shaped asterism lies 5deg to p and slightly S of this. Target is visible as an elongated patch in finder about 1deg N of this group.
Has a number of bright stars arranged in a “cascade” running NS. Chart indicates this lies on Sp side of cluster. Many other bright stars fill field at 67x Very nice Open Cluster.

Post observation notes. O’Meara lists this cluster at number 39 in his list of Hidden Treasures. DSS image here http://spider.seds.org/ngc/ngcdss.cgi?obj=NGC!2301&r=6:51.8&d= +00:28&e=J2000&h=15&w=15&f=GIF&c=no ne certainly doesn’t do it justice as it is a very satisfying object in the eyepiece.

NGC 2353 Open Cluster in Monoceros
RA 07 14 31.0 Dec -10 16 00 Mag 7.1 Diam’ 18 No of Stars 106 Brightest Star Mag 9.0 Type cl

Sits around middle star of a line of 3 mag 6 stars about 4deg to Sf of M50. Has about 30 moderate brightness stars in a wide group. Seems to be arranged in 2 groups when examined closely. South group is quite round and N group it elongated.

NGC 2440 Planetary Nebula in Puppis
RA 09 27 03.5 Dec -56 06 18 Diam” 117 Mag(P) 12.2 Mag(V) 11.8 Mag Cent Star 15.9

Very small but quite bright Planetary Nebula. Slightly elongated with a faint green tinge. OIII filter shows very well.

Post observation notes. Nice image of NGC 2440 is here http://www.noao.edu/outreach/aop/observers/n2440.html O’Meara lists this cluster at number 41 in his list of Hidden Treasures. He indicates that at high power the central star can be observed in a 10” scope but I saw no evidence. It would be an interesting object to see as the surface temperature of the star is estimated at 200,000degrees C, making it one of the hottest stars ever measured. NGC 2440 is also an example of a Planetary Neb with multiple lobes, with observers seeing 3 lobes rather than the more common 2.

Malcolm