[barx1963 (Malcolm)]

Despite my earlier pessimism, managed to get a couple of productive hours in last night

Observing Report 8/12/10


All observations made using Dobsonion mounted 305mm Newtonian reflector at f/5. Eyepieces use are 34mm Meade 4000(44x) 24mm Panoptic (67x) 13mm Nagler T6 (115x) or 13mm Nagler with Barlow (230x)

Charts - Uranometria 2000 (2nd ed.) Data derived from Uranometria (2nd ed) Deep Sky Field Guide.

Observations 3/12. Seeing good, transparency fair. Some Light Pollution as usual

NGC 1566 Galaxy in Dorado
RA 13 16 00.9 Dec -02 25 39 Mag(V)13.0 Dim’ 1.5x1.0 SB 13.3 Class (R’)SB(rs)00 pec

Locate Alpha Doradus by naked eye. There is a 1 deg wide equilateral triangle of mag 5/6 stars about 2deg to Np. Follow line of 2 p stars to S about 50’ to a mag 8 star. Galaxy lies just f of it. A very faint mag 12 star is superimposed of f edge of galaxy. Target is fairly large, appears to have a bar running NS. Knots in outer envelope evident with averted vision.

NGC 1617 Galaxy in Dorado
RA 04 31 40.3 Dec -54 36 12 Mag(V)10.4 Dim’ 4.3x2.1 SB 12.7 Class SB(s)a

Lies about 20’ Np of Alpha Doradus. Core easily seen. At higher power (113x) and with averted vision, there is a suggestion of a large spindle shape with an EW orientation. Bracketed by 3 faint stars estimated mag 11-12. IC2085 lies nearby but not located.

NGC 1672 Galaxy in Dorado
RA 04 45 42.2 Dec -59 14 41 Mag(V)9.7 Dim’ 6.6x5.5 SB 13.4 Class SB(s)b II

From Kappa Doradus, move 40’ to Nf to a mag 6.5 star. Galaxy lies about 10’ to p. Bright stellar like core with faint outer envelope. Some spiral structure appeared evident with averted vision.

NGC 2243 Open Cluster in Canis Major (December Challenge object)
RA 06 29 35.0 Dec -31 17 00 Mag9.4 Diam’ 8.3 No. of Stars 368 Mag Brightest Star 11.8 Type cl Open Cluster

Locate Zeta Canis Majoris, about 2.5deg to Sp is a wide pair of Lambda and IY Canis Majoris. Cluster lies just p of a mag 7.5 about 1deg 10’ to N. A faint haze of starlight with maybe 3 mag 11 stars bracketing it. A number of similar brightness stars appear within cluster itself which may be foreground stars.

NGC 1261 Globular Cluster in Horologium (December Challenge object)
RA 03 12 15.3 Dec -55 13 01 Total Vm 8.3 Brightest Star Vm 13.5 HB Vm 16.8 Diam’ 6.8 Conc Class 2

Locate wide double Zeta Reticuli, proceed via Mu Horologii, then via TW Horologii. Cluster lies 2deg due N. Easily visible at low power. Fairly large with an even glow with no obvious core.
NGC 1252 Open Cluster in Horologium
RA 03 10 56.0 Dec -57 46 00 Diam’ 9 No. of Stars 18 Mag Brightest Star 6.7Type ast Asterism

Mag 6.5 star 40’ to Sp of TW Horologii. Very loose open cluster with no central condensation. Onlu about 7/8 stars clearly visible.

NGC 1851 Globular Cluster in Columbo (December Challenge object)
RA 05 14 06.3 Dec -40 02 50 Total Vm 7.1 Brightest Star Vm 13.2 HB Vm 16.1 Diam’ 12 Conc Class 2

Very bright GC with dense core. Averted vision reveals a very large outer shell that dissipates into easily resolved stars of maybe 14/15 mag. This agrees with Uran 2000 data and notes by Gottlieb on NGC/IC project.

NGC 1808 Galaxy in Columba (December Challenge object)
RA 05 07 42.8 Dec -37 30 51 Mag(V)9.9 Dim’ 6.5x3.9 SB 13.3 Class (R)SAB(s)a

About halfway between NGC 1851 and Lambda Caeli. Very bright core, spindle shaped and aligned roughly NS.

NGC 1792 Galaxy in Columba (December Challenge object)
RA 05 05 14.8 Dec -37 58 48 Mag(V)10.2 Dim’ 5.2x2.6 SB 12.9 Class SA(rs)bc II-III

Lies about 20’ to Sp of NGC 1808 and appears as almost a smaller twin of that galaxy. Both appear in same field at 67x. This object is noticeably less bright that its companion.

NGC 2298 Globular Cluster in Puppis (December Challenge object)
RA 06 48 59.2 Dec -36 00 11 Total Vm 9.3 Brightest Star Vm 13.4 HB Vm 16.2 Diam’ 5 Conc Class 6

Lies 3.5deg due S of Kappa Canis Majoris. Small fairly faint, no obvious core. Averted vision helps to “mottle” the cluster. 3 or 4 stars of approximately 13 mag are resolvable.

Malcolm