At The Eyepiece, by Mike Ethier
December and January are the two least productive months for this observer. December seems to be perpetually cloudy, and January clear nights, when they appear, are usually bitter cold. However, by the latter part of February and early March things begin to seem hopeful again, and regular observing often resumes at this time. This is good news for those of us who like to study objects in Orion. While beautifully situated in January, unless you are in the Florida Keys waiting later in the season is a more practical viewing option. Most of my deep sky work in Orion takes place at the end of February and early March. Much of Orion is still well placed in the sky into late March. I have selected a few smaller and out of the way sights this month. There is more to Orion than its Messier wonders! So if you don’t want to tackle the following objects now, be patient and wait a week or two.
The four open clusters and lone planetary nebula I will talk about this month can be found on Chart 96 of the Uranometria 2000 Atlas, All Sky Edition. This is by far the best hands-on sky atlas available, useful in the field and infinitely fun to browse at home. North of Betelgeuse and Bellatrix is a wide asterism of bright stars, centred on Meissa. The southern-most bright star of this group is Phi-2 Orionis, also numbered as 40. South following this star is pn 2022. The nebulae is very bright in a 12” mirror, and obvious at 100x. No filter is necessary. Observed at 100x through 272x, the edges appear dimmer and less evenly lit than the central area. Though a good object for a 12”, an 8” should also show it well. It’s small size seems to aide its brightness. Use a moderately high power.
Moving 3 degrees north of Betelgeuse and about 8 minutes following, oc 2141 appears at low power as a low surface brightness haze. I enjoy the challenge of this kind of cluster, having hopes that a 12” mirror will show its secrets at higher powers. At 60x and 100x the cluster is quite large, sitting among a few brighter stars laid over top. At 136x there is some resolution of the faint haze, including a tight knot of stars near centre. More stars come out to play at 200x, including many that are very, very faint (16th mag.?). At 272x more clumps and knots are seen, popping out right down to visual threshold. A night with good transparency is a big help with this faint but rewarding group.
2 degrees N of oc 2141, and about 11’ following, is oc 2194. Already resolving nicely at 60x and 100x, this is a very enticing cluster in a 12” mirror! A notable arm of stars extends south preceding. At 136x the cluster is rich and bright. However, with my mirror stopped down to 8” the stars are now pretty faint. 187X and full aperture gives a very remarkable view, showing many brighter stars (mag. 13) overtop reams of much fainter ones. This is a highly recommended group, and would be stunning in the club’s 14” scope. Immediately following oc 2194 is oc Skiff J0614.8+1252. Two separate star groups are noted, almost adjacent, and just north following the larger cluster. The actual cluster is the group closest to oc 2194. At 136x and 187x, it is a faint, circular group of stars just north of 3 brighter stars. The other separate group, a brighter asterism, is in the same field of view at moderately high power. The Skiff group is fainter than this, and richer in stars.
North preceding oc 2194 is oc 2169, an interesting object as it also receives designation as a multiple star in the Struve catalogue, #848. At least half the interest is the multiple star, which could be extended with even more than its 5 main members. The cluster is bright and well resolved at 60x. It is an attractive cluster, and appears in two distinct sections. 100X and 136x show 10 stars in the main group, and 7 in the secondary section. Struve 848 has a main pair of mag. 7.5-8 stars at 2.6” apart. These were split nicely at 100x and 136x. A mag. 12 star is 14” away, seen at 136x. In addition, there is a mag. 8 star at 28”, and a mag. 9 star at 43”.
Object Statistics
pn 2022: Size 39”; Vis. Mag. 11.6; Central star mag. 15.8.
oc 2141: Size 10’; Vis. Mag. 9.5; Brightest star mag. 15.
oc 2194: Size 9’; Vis. Mag. 8.5; Brightest star mag. 13.
oc Skiff: Size 5’; About 20 stars.
Oc 2169: Size 6’; Vis. Mag. 5.9; Brightest star mag. 6.9.
Messier Of The Month: Messier 78 in Orion
Definitely an object that does not receive as much love as M 42, it is best to study M 78 before observing its more famous and spectacular cousin. Discovered by Mechain in 1780, it is a reflection nebula, part of a group of similar objects lying about 1350 light years away. Nebula filters don’t help much with this kind of object, and fortunately aren’t required for good visual views. When taken on its own (without comparing it to M 42), M 78 is bright, pretty large, and impressive at high powers, where good detail shows in its varying brightness and irregular shape. 60X and 100x show a moderate-sized, moderately bright irregularly shaped haze surrounding two mag. 10 stars. These stars act as the illuminators of M 78. It appears to extend south, and narrows in that direction. 136X shows it well. Just north of M 78 lies gn 2071, a nebula surrounding two bright stars that is obvious at 60x and 100x. The brighter star is V 1380, a variable, and is the star with the most notable haze around it. At 136x the star splits into a double (9.7-11.5/10”?). A third nebula, gn 2067, is immediately north preceding M 78. It is small and faint, located just south of a faint star. I use this one to demonstrate just how wonderful M 78 is by comparison. A 4th nebula lies just south preceding (gn 2064), but I have yet to see this one visually. I shall try again later in the winter. The objects are shown on Chart 116 of Uranometria 2000, along with many other small, faint nebula.
Object Statistics:
Messier 78—gn 2068: 8’ x 6’; Reflection nebula.
Gn 2071:--7’x 5’; Reflection nebula.
Gn 2067:--8’ x 3’; Reflection nebula.
Gn 2064:--1.5’ x 1’; Reflection nebula.
Mapman Mike
