Here are my notes from the observing session with John Flannery and Michael Murphy at Cloon Wood last Friday night/Saturday morning. This was certainly the best night so far this year with hopefully many more to come. Although bitterly cold at -3º, the wind was light so wind chill was minimal making for a more comfortable night. Some cloud appeared for a while around 22.45 UT but cleared reasonably quickly. Would have stayed beyond 03.00 but cold and tiredness finally took their toll.
Date / Time: 21.30 UT Friday 3rd March 2006 to 03.00 UT Saturday 4th March 2006
Location: Cloon Wood, Glenmalure Valley, Enniskerry, Co. Wicklow
Seeing: 4/10
Transparency: 5/10
Telescope equipment: NexStar 8 GPS at f/10; Tele Vue 13mm T6 Nagler (155x); Tele Vue 31mm T5 Nagler (65x); Tele Vue 18mm Radian (112x).
Notes: PA (Position Angle) Orientation = Compass angle measured from N counter-clockwise. N = 0º - E = 45º - S = 180º
M = Mag. (V). SB = Surface Brightness.
ORION
Messier 42 (NGC 1976) – Bright Nebula
Messier 43 (NGC 1982) – Bright Nebula
NGC 1977 – Bright Nebula associated with a sparse group of stars
NGC 1973 – Bright Nebula associated with KX Orionis
Viewing the Orion Nebula complex with the 2-inch 31mm T5 Nagler is an absolutely gorgeous sight – I imagine looking at it through a porthole in a spaceship is something akin to the experience provided by this eyepiece – and I couldn’t break away from that view for a while as I examined the area in detail. From the arc of three stars N of Messier 43, 42 Orionis, V359 Orionis and 45 Orionis, running E-W and the dim nebulosity around them (NGC 1977), brightest parts being to the S and W; the tiny nebulous patch of NGC 1973 surrounding the star KX Orionis; the nebulosity surrounding Nu Orionis (Messier 43), its shape round with a hint of an extension to the NE; the gaping Fish Mouth in Messier 42; the nebulous wings of M42 spreading out like a giant bird until they finally merge into the blackness beyond (the E wing clearly sharper and more defined than the W wing); the four principal stars of the Trapezium (Theta Orionis¹) in the centre; binary Theta Orionis² 2’ to the SE of the Trapezium; the brilliant but unequal blue and white double star Iota Orionis to the S and close by, the gorgeous white double Struve 747. Beautiful!
GEMINI
M35 (NGC 2168) – Open Cluster
NGC 2158 – Open Cluster
Messier 35 is generally regarded as the finest galactic cluster in the winter sky. At 112x, the NexStar 8 revealed countless dozens of stars with chains running out from a dark hole in the centre, which contained just a few faint stars. This dark hole seemed to run into another dark patch to the SE. With a separation of 30.9", the magnitude 8.5 and 9.8 components of double star Otto Struve 134, lying NE of the centre of Messier 35, was a very easy split. Moving 30’ off the SW edge of M35, NGC 2158 glowed like a giant snowball and increasing power to 155x began to resolve a number of stars in this distant cluster.
AURIGA
Messier 36 (NGC 1960) – Open Cluster – M = 6.0 – 60 stars
Messier 37 (NGC 2099) – Open Cluster – M = 5.6 – 1842 stars
Messier 38 (NGC 1912) – Open Cluster – M =6.4 – 160 stars
NGC 1907 – Open Cluster – 117
Messier 38 comprises a lovely mixture of bright and fainter stars with dozens easily resolved. The NexStar 8 displayed a conspicuous dark void in the centre with a bright star (which is in fact a triple star system), and a prominent dark lane extending towards the N reminiscent of a keyhole. Moving the scope 30’ S, I picked up NGC 1907, a compact cluster often overlooked by observers with about 30 stars resolved.
Although Messier 36 is a smaller and sparser cluster than M38, the stars appeared somewhat brighter. Did not count the stars but probably 45/50 stars resolved in a crooked Y-shaped pattern. At 112x, I could see doubles to the S and SE (the most southerly pair being Struve 737), a dark void to the north of centre and lovely chains of stars meandering out from the centre.
Messier 37 is undoubtedly the finest of the Auriga clusters for medium aperture telescopes when the cluster resolves into a myriad of sparkling star points. Again, I didn’t bother counting the stars but well over 100 against a gorgeous haze of unresolved stars. Just SW of the centre was a 9th magnitude orange/red star (Burnham describes this “ like a ruby on a field of diamondsâ€). At 112x, I could see dark lanes running N-S and NE-SW and a dark void SE of centre containing just one 12th magnitude star. What a wonderful cluster to observe!
LEO
[Leo Triplet]
Messier 65 (NGC 3623) – SAB – M = 9.3 SB = 12.8
Messier 66 (NGC 3627) – SAB – M + 8.9 – SB = 12.7
NGC3628 – Sb – M = 9.5 – SB = 13.4
The Leo Triplet, comprising Messier 65, Messier 66 and NGC 3628, was the first target on the night’s galaxy tour. Messier 65 appeared as nice elongated halo in a PA of 175º (N-S) with a brighter core in the centre. It seems a bit larger than its companion, Messier 66 with the latter also elongated in a PA of 175º (N-S). Messier 66 was the more interesting of the pair as it displayed some signs of outside its bright core. Edge-on spiral NGC 3628 is the largest of the three galaxies, and although fainter than Messier 65 and 66, it was still easily seen as a long pencil-shaped galaxy at a PA of 50º (E-W) framed nicely by two bright stars N and S of the W end. All three galaxies fitted into the FOV of the 31mm Nagler.
NGC 3607 – SA – M = 9.9 – SB = 12.9
NGC 3608 – E2 – M = 10.8 – SB = 13.1
This pair of galaxies was a nice sight both in the 13mm and 31mm Nagler FOVs. At 155x, NGC 3607, the spiral galaxy to the S, appeared larger and brighter than the elliptical NGC 3608 with a bright concentrated core. Otherwise, both galaxies seemed quite similar.
NGC 3626 – SA – M = 11.0 – SB = 12.6
NGC 3626 was faint, small and round with a sharp condensed nucleus.
Messier 105 (NGC 3379) – E1 – M = 9.3 – SB = 12.8
NGC 3384 – SB – M = 9.9 – SB = 12.6
NGC 3389 – SA – M = 11.9 – SB = 13.2
What a view - all three galaxies visible in the same FOV at 155x. Messier 105 was clearly the largest and brightest galaxy of the trio with a fine bright core – PA 70º (ENE-WSW) . NGC 3384 did not seem that much fainter and had a bright nucleus as well – PA 50º (NE-SW). Although quite faint, NGC 3389 was easily visible as an elongated hazy patch in a PA of 110º (ESE- WNW).
NGC 3377 – E5-6 – M = 10.4 – SB = 13.3
NGC 3377 is quite a small galaxy but showed some elongation in a PA of 35º (NE-SW) and had a very concentrated almost stellar nucleus.
NGC 3412 – SB – M = 10.5 – SB = 12.6
NGC 3412 is another small galaxy, appearing as a round halo with a condensed bright nucleus in the centre.
Messier 95 (NGC 3351) – SB – M = 9.7 – SB = 13.5
Messier 96 (NGC 3368) – SAB – M = 9.3 – SB = 13.1
Of these two Messier objects, Messier 96 clearly seemed to be the brightest of the pair, perhaps because of its bright condensed core compared to Messier 95, which has a similar overall brightness but a dimmer core.
VIRGO
NGC 4754 – SB – M = 10.6 – SB = 13.1
NGC 4762 – SB – M = 10.3 – SB = 13.1
NGC 4754 – small round diffuse galaxy with a bright condensed core located 11’ SE of and in the same FOV as NGC 4762. 4762 appeared as an edge-on spiral in a lovely setting with three 9th/10th magnitude stars. With lesser aperture, the stars may tend to overwhelm the galaxy but the NexStar 8 and 13mm T6 Nagler displayed a beautiful but small central bulge with bright stellar nucleus and needle arms stretching to the NE and SW. This galaxy is really worth seeking out with medium to large aperture.
[Arp 116]
Messier 60 (NGC 4649) – E2 – M = 8.8 – SB = 12.9
NGC 4647 – SAB – M = 11.3 – SB = 13.2
Messier 60 is one of the brightest galaxies in Messier’s list – discovered by Johann Gottfried Köhler in 1779 while observing Comet Bode and independently by Messier just days after Köhler. Appeared as a large circular halo with a bright diffuse core. M60 has an interacting spiral companion, NGC 4647, only 2.5' to the NW, which Messier did not see and many observers overlook. In my 8-inch telescope, this face-on spiral galaxy appeared as an unconnected faint misty patch somewhat smaller than M60.
[Arp 120]
NGC 4435 – SB – M = 10.8 – SB = 12.5
NGC 4438 – SA – M = 10.2 – SB = 13.6
NGC 4435 and NGC 4438 are spectacular interacting galaxies commonly referred to as The Eyes. Both were clearly visible in the same FOV at 155x with 4435 in PA 15º appearing slightly smaller than 4438 with a brighter stellar nucleus. 4438 in PA 20º just seemed that bit larger and more diffuse with a bright core.
NGC 4402 – Sb – M = 11.7 – SB = 13.2
Said to be much more difficult than nearby Messier galaxies, I found NGC 4402 to be quite a bright galaxy elongated in PA 90º (E-W) with a fine central bulge and brighter core.
Messier 84 (NGC 4374) – E1 – M = 9.1 – SB = 13.0
Messier 84 showed up as a large bright oval haze with a strong bright core and almost stellar nucleus - galaxy slightly elongated in PA 135º (SE-NW).
Messier 86 (NGC 4406) – E3 – M = 8.9 – SB = 13.2
Messier 86 was in the same FOV as Messier 84 using the 31mm T5 Nagler. With the 13mm T6, Messier 86 appeared very similar to Messier 84, a large bright diffuse glow with a bright core and almost stellar nucleus elongated very slightly in PA 130º (SE-NW).
NGC 4388 – SA – M = 11.0 – SB = 13.0
NGC 4388 was barely visible as a large elongated diffuse glow in PA 90º (E-W) with just a hint of a brighter core.
NGC 4387 – E – M = 12.1 – SB = 12.9
NGC 4387 appeared as a reasonably bright round diffuse halo with a brighter core.
NGC 4425 – SB0 – M = 11.8 – SB = 12.9
NGC 4425 only appeared as a very faint hazy patch without any really defined shape and just a hint of a brighter core.
Messier 59 (NGC 4621) – E5 – M = 9.6 – SB = 12.9
Although not as prominent as Messier 60, Messier 59 is still a fine bright elliptical galaxy with a large diffuse halo and brighter core. Shows a slight elongation in PA 135º (SE-NW).
Messier 58 (NGC 4579) – SAB – M = 9.7 – SB = 13.1
Somewhat fainter than Messier M59, Messier 58 showed itself as a round diffuse glow slightly elongated slightly in PA 90º (E-W) with a brighter core and stellar nucleus.
Messier 89 (NGC 4552) – E0-1 – M = 9.8 – SB = 12.5
Messier 89 showed up as a large elliptical galaxy with a round diffuse halo, concentrated towards the centre with a stellar nucleus.
Messier 90 (NGC 4569) – SAB – M = 9.5 – SB = 13.4
Messier 90 appeared as one of the largest galaxies viewed tonight. Unlike most of the other bright Messier galaxies above, Messier 90 is a spiral. Elongated in PA 15º (NNE-SSW), the galaxy appeared to have a stellar nucleus but this is in fact a 12th mag. star.
VV219 (Atlas of Interacting Galaxies)
NGC 4567 – SA – M = 11.3 – SB = 13.1
NGC 4568 – SA – M = 10.8 – SB = 13.1
NGC 4567 and NGC 4568 are listed in the Atlas of Interacting Galaxies as VV219 although Burnham poses the question as to whether NGC 4567 and NGC 4568 are actually connecting, as apparently, they display none of the usual signs of interaction and may very well be some distance apart. NGC 4567 is receding at 2,121 km/s and NGC 4568 at just 1,055 km/s. These galaxies are commonly referred to as the Siamese Twins, and, interacting or not, these spirals are a beautiful sight in a telescope. With the NexStar 8 GPS and 13mm T6 (155x) the galaxies appeared as two large clearly overlapping diffuse haloes with no distinct core or nucleus.
NGC 4564 – E – M = 11.1 – SB = 12.9
While observing the Siamese Twins, I noticed a third galaxy to the N in the same FOV; this turned out to be NGC 4564, an elliptical galaxy appearing as a hazy patch elongated at a PA of 45º (NE-SW).
NGC 4461 – SB – M = 11.2 – SB = 12.8
NGC 4458 – E0-1 – M = 12.1 – SB = 13.1
This pair of galaxies, NGC 4461 and NGC 4458, provided a stunning view, similar to NGC 4435 and NGC 4438 (The Eyes) but a bit fainter. 4461 to the N was the brighter of the two and displayed a nice bright core. 4458 had a more diffuse halo and a more condensed core.
NGC 4216 – SAB – M = 10.0 – SB = 12.8
NGC 4216 is a really nice edge-on spiral galaxy and displayed a an elongated bright core with needle arms tapering off E-W
Messier 104 (NGC 4594) – SA – M = 8.0 – SB = 11.6
Messier 104, the Sombrero galaxy is one of the most observed galaxies in the Virgo Cluster and an obvious galaxy on tonight’s observing list. I could easily see the large central bulge and arms and, although not especially prominent, both John and I detected the dark lane cutting across the core.
Quasar 3C 273 – M ~ 12.8 (Absolute mag. –26.7)
It’s been a few years since I last observed the brightest quasar in the sky, 3C 273. It’s not too difficult to locate manually once you learn the signposts (took me an hour the first time many years ago though!) but the NexStar 8 placed the final triangular asterism centre FOV. With a redshift of 0.1575 and a distance of 2.5 billion LY (800 Mpc), this was not just the most distant object observed tonight but also one of the most distant objects visible with 8-inch aperture. Visually, it’s just a fuzzy star but think of the distance and what this exotic object represents and it becomes far more than that. John, Michael and myself all viewed and confirmed the sighting without even using averted vision. 3C 273 has varied in brightness between 12.5 and 12.85 over the past 25 years and is around 12.6 at the moment. I could also see the faint star close to the quasar, again without averted vision. The magnitude allocated to this star differs according to various catalogue sources but is in and around 13 to 13.5. I researched this a few years ago and came to the conclusion after observation that it is probably closer to 13.5 than 13. It certainly seemed fainter than 3C273 as observed tonight by probably 0.7 mag. so reaching over 13th magnitude on a night of indifferent transparency really pleased me.
CANES VENATICI
[Arp 281]
NGC 4631 – SB – M = 9.2 – SB = 12.8
NGC 4627 – E4 pec – M = 12.4 – SB = 13.1
NGC 4656 – SB – M = 10.5 – SB = 13.5
NGC 4657 – SB – M = 10.9 – SB = 10.5
Spindle galaxy NGC 4631 (the Whale Galaxy) provided a lovely view. This huge edge-on spiral seemed to fill almost the full width of the FOV displaying a bright central core tapering towards the E and W edges, especially noticeable on the W side where it tapered to a point. Some mottling was quite noticeable along this galaxy. A 12th magnitude star was prominent on the northern edge of the bright central core. Just 2’ NW of this star, I could just about detect the diminutive peculiar elliptical galaxy, NGC 4627, as a faint round blob. The thicker E end of 4631 is distorted by its interaction with NGC 4656, a peculiar spiral galaxy lying 30’ to the SE and oriented at a PA of 135º (NE-SW). At one time, NGC 4656 was thought to be two interacting galaxies (and may still be as the NGC/IC Project leaves it open) with the bright NE edge designated NGC 4657. Visually, the bright area of 4656, seems to be at the SW edge, but is in fact the core as the W arm is much fainter and more difficult to see; I certainly saw no trace of it. The bright NE edge is badly distorted at a 90º angle to the main structure of the galaxy. 4656 / 4657 has been aptly described as a celestial hockey stick!
SEXTANS
NGC 3115 – S0 – M = 8.9 – SB = 11.9
John mentioned he was looking for NGC 3115 in Sextans so I dialled it in. The Spindle Galaxy, NGC 3115, is a lenticular galaxy (intermediate between pure spheroidal systems like luminous ellipticals and disk-dominated spiral galaxies) with a massive black hole at its centre. This turned out to be a nice bright typical looking lenticular galaxy at 155x, its elongated bright halo with brighter core clearly oriented in a PA of 45º (NE-SW).
NGC 3166 Group
NGC 3166 – SAB – M = 10.4 – SB = 12.8
NGC 3165 – SA – M =13.9 – SB = 13.8
NGC 3169 – SA – M = 10.4 – SB = 12.8
While in Sextans, I decided to take a look at the NGC 3166 Group comprising NGC 3166, NGC 3165 and NGC 3169. 3166 showed up as a reasonably bright oval haze oriented at a PA of 90º (E-W) with a brighter core. To the NE in the same FOV was 3169, a similar oval haze with a bright core and almost stellar nucleus, oriented in a PA of 45º (NE-SW). I’ve seen this pair also referred to as The Eyes and it does bear a striking resemblance to its Virgo counterpart. I could not detect the much fainter galaxy in the 3166 Group, NGC 3165. 3166 and 3169 provided a beautiful sight, especially when I switched to the wider FOV of the 31mm T5 Nagler, which also brought NGC 3156 (not a Group member) into the FOV as well.
COMA BERENICES
Messier 85 (NGC 4382) – SA – M = 9.1 – SB = 13.0
NGC 4394 – SB – M = 10.9 – SB = 13.4
Messier 85 appeared very like Messier 86, i.e. round and bright but with a brighter core than M86. NGC 4394 was easily visible to the E, a nice diffuse glow with no discernible core. There is a 10th mag. star on the SE edge.
NGC 4565 – SA – M = 9.6 – SB = 13.2
NGC 4565 is one of the classic edge-on spiral galaxies and a favourite of all deep sky observers so I couldn’t finish the night without observing it. Although it seemed a bit fainter than I remembered from my last observation (with a 10-inch though), its beautiful central bulge and needle arms stretched across the centre of the FOV with the dust lane just about visible. This was a really nice end to galaxies for the night before finishing the session with a couple of favourite globular clusters in Ophiuchus.
OPHIUCHUS
Messier 10 – M = 6.6 – Class = 7
Messier 12 – M = 6.1 – Class = 9
In appearance, these two globular clusters are quite dissimilar. Messier 12 resembles an open cluster in ways, being quite loosely packed and with streamers of stars in all directions. It was easily resolved right into the centre at 155x. Messier 10, on the other hand, appeared brighter and more concentrated, and although the outer areas were easily resolved, the very tightly packed central core area defies resolution.
