Hi All,
Below is my report of observations made from my nearly-dark site last weekend on 19-20/092009. We had an interesting very mix of conditions including some I’ve never observed in before – burn-off smoke.
The day started with an unsullied sky but over the day some high cloud started to build up but I felt it was likely to clear in the early evening so I headed out early with a few of my Sutherland Astronomical Society mates to our site in the southern highlands. Driving up the last few kilometres my heart started to sink a bit – bushfire smoke. More corrrectly it was hazard reduction burning. On arrival just after 5pm there as a large burn-off happening about 1-2km west and the smoke was going straight over us – yuk. Let’s hope they get it over and finished soon.
As it happened, over the next two hours we has two RFS vehicles come up the bush track to the strip, turn their lights on full-beam and blind us all while the smoke was on and off, on and off for most of the early part of the night. We learned it would be allowed to burn all night. The higher smoke was over not long after sunset but the smouldering stuff that creeps along the ground in light winds went on all night and periodically, the low smoke from that would creep over us producing stinging eyes and an unpleasant smell. It was so bad a couple of times we had to stop completely and cover the optics and … wait. The insides of the car a week later still smell like a bushfire. A green laser produced brilliant, almost blinding beams through the smoke. For more than ˝ the time the smoke blew the other way and we had a good sky – particularly later on after 10.30pm.
The seeing was not brilliant but somewhat variable, at times 4/10 and not 10minutes later 6/10. At the start of making recorded observations. The SQM readings at the start of the evening when some of the cirrus cloud and smoke was problematic was 20.65 but by the end of the night at 2am it was 21.38 okay but not brilliant.
I started at 8.30pm by dropping in on a few PNe in Aquila and Delphinus that I couldn’t recall having seen in the larger ‘scope they were worth the visit – particularly NGC 6905:
x185 27', x247 20', x317 15', x462 11'
NGC 6803 PK 46-4.1 Planetary Nebula *
RA: 19h 31m 16.6s Dec: +10° 03' 20"
Mag: 11.3 (P) Size: 6.0" Class: 2a Mag C. Star: 15.2
This PNe is essentially stellar at x185, and just shown as non-*ar at x247. It is the mid-most star, a little off-centre to the S in a line of similarly bright *s mags 10, 11 & 11 N-S just 3' long. The N-most star has a small companion and there are a few other small stars close-by. At x317 it is non-stellar and has a lower SB than the other stars. Probably no more than a few arc-seconds diameter with a tiny amount of fuzz outside that, round. Reacts strongly to the UHC filter and OIII. No cent * visible. Weakly bluish tint without the UHC or OIII.
x247 20', x317 15',
NGC 6891 PK 54-12.1 Planetary Nebula *
RA: 20h 15m 09.0s Dec: +12° 42' 12"
Mag: 11.7 (P) Size: 21.0" Class: 2a+2b Mag C. Star: 12.4R.V.: ---
Source: Str-ESO *
This is a quite small PNe that is maybe 20" diameter all told. In a fairly well populated field. It has at lower powers a light pale-blue colour which tends to wash out somewhat at x247 & x317. The outer halo has lowish SB diffuse-edged and rises slightly to centre. The round inner halo is about 10" diameter and not particularly well defined at the edges and is slightly more strongly coloured and grows slightly to centre. With the UHC it brightens somewhat to considerably, not much more detail, perhaps a little better defined at the edge, but the distinction between the inner and outer halos is now a little less distinct.
x247 20', x317 15', x462 11' TF
NGC 6905 PK 61-9.1 Planetary Nebula *
RA: 20h 22m 23.0s Dec: +20° 06' 16"
Mag: 11.9 (P) Size: 72.0"x37.0" Class: 3+3 Mag C. Star: 15.7
R.V.: --- Source: Str-ESO *
This is a really beautiful PNe. At x317 unfiltered it appears on the W side of a small box of 4 mag 11 & 12 *s only about 2.5' a side. It is between the brightest and 3rd brightest in the box. Seems to be elong in PA 0 60" x 40" as a reasonable SB oval disc that seems to have some weak brightenings that make it look just a little like M27 -- the Dumbbell. Dividing the PNe into quadrants with an "X" (as opposed to a "+") the E quadrant is a little brighter than the average of the surface brightness and W is 2nd brightest. The W quadrant seems to have a harder edge than elsewhere.
The central star is just visible at threshold as the seeing comes and goes -- very, very faint about mag 15.5 and is not really improved at x462 because the seeing won't cooperate. Overall shape at x317 -- seems round but with small extensions to the N and S ends, the S one is a little brighter than the N and almost reaches out to the mag 12 * at that corner of the box. With a UHC and OIII filter it seems more evenly illuminated at x317 and x462.
An image is here
http://www.winer.org/ngc6905-MS.jpg
though N is to the right and E is up.
I then went to have a look at Abell 72 but the smoke came in and that was it for serious observing some time. After that it was time for some galaxies in Cetus. The best bit for the night was the Hickson 16 group.
185 27' x247 20'
NGC 345 Galaxy *
RA: 01h 01m 22.1s Dec: -06° 53' 05"
Mag: 13.5 S.B.: --- B-V: --- Size: 1.4'x0.8'
Class: SA(s)a: P.A.: 138 Inclination: --- R.V.: --- Source: RC3 *
NGC 349 Galaxy *
RA: 01h 01m 50.8s Dec: -06° 48' 01"
Mag: 13.5 S.B.: --- B-V: --- Size: 1.3'x1.2' Class: SA0-
P.A.: 49 Inclination: --- R.V.: --- Source: RC3 *
NGC 350 Galaxy *
RA: 01h 01m 56.6s Dec: -06° 47' 47"
Mag: 15.3 S.B.: --- B-V: --- Size: 0.6'x0.4' Class: E/S0
P.A.: 82 Inclination: --- R.V.: --- Source: PGC *
NGC 356 Galaxy *
RA: 01h 03m 07.1s Dec: -06° 59' 19"
Mag: 13.5 S.B.: --- B-V: --- Size: 1.8'x1.2' Class: SAB(s)bc pec:
P.A.: 53 Inclination: --- R.V.: +5891 Source: RC3 *
NGC 340 Galaxy *
RA: 01h 00m 34.9s Dec: -06° 51' 59"
Mag: 15.2 S.B.: --- B-V: --- Size: 0.9'x0.4' Class: Sb
P.A.: 71 Inclination: --- R.V.: --- Source: PGC *
NGC 342 Galaxy *
RA: 01h 00m 49.8s Dec: -06° 46' 23"
Mag: 14.5 S.B.: --- B-V: --- Size: 0.9'x0.4'
Class: E P.A.: 107 Inclination: --- R.V.: --- Source: PGC *
NGC 347 (IC 71) Galaxy *
RA: 01h 01m 35.2s Dec: -06° 44' 03"
Mag: 14.5 S.B.: --- B-V: --- Size: 0.5'x0.4' Class: SB
P.A.: 1 Inclination: --- R.V.: --- Source: PGC *
MCG -1-3-59 PGC 3630 Galaxy *
RA: 01h 00m 53.3s Dec: -07° 02' 24"
Mag: 15.7 S.B.: --- B-V: --- Size: 1.0'x0.9' Class: SBc
P.A.: 47 Inclination: --- R.V.: --- Source: PGC *
NGC 345 is probably the 2nd brightest of this group and is found to the SW by 5' from a 7th mag * as a small lowish SB round spot maybe 50" diameter growing broadly and slightly to the centre where there is a very faint tiny spot but no real core or nucleus.
-49 is less than 5' E of that mag 7* which is very distracting. It is about at the 1/2 way point between that * and another mag 11* 7' E of it. Similar to -45 but maybe a tad brighter, almost 1' diameter growing broadly and moderately to centre, round, has slightly higher SB than -45 and occasionally visible tiny faint spot at centre.
-50 is between it and the mag 11 * and is no more than a 15" diameter spot of very very faint mist.
-56 is 25' SE of that mag 7 * just outside the field with the others. Pretty barren field here, small, slightly oval in PA 45 and about 1.25' x 40" lower SB than the first two, grows broadly and weakly to centre where there is an occasionally visible faint spot.
-47 is N of the mag 7 * by about 5' and is a tiny 15" diameter spot of mist. -42 is 10' WNW and is the same though a little easier to see because it is further from the star and -40 is to the SW by 15' and is a little fainter but has no structure.
A line drawn from the mag 7* through -45 and extended 2x brings the smallest and faintest of the lot MCG -1-3-59 that is visible at threshold as a tiny round spot of gossamer.
x185 27'
NGC 564 Galaxy *
RA: 01h 27m 48.3s Dec: -01° 52' 46"
Mag: 13.5 (B) S.B.: 13.3 B-V: +1.01 Size: 1.3'x1.1'
Class: E P.A.: 144 Inclination: --- R.V.: +5790 Source: RC3 *
NGC 560 Galaxy *
RA: 01h 27m 25.4s Dec: -01° 54' 46"
Mag: 14.0 (B) S.B.: --- B-V: +0.98 Size: 2.0'x0.4' Class: S0^ sp
P.A.: 178 Inclination: 6 R.V.: +5483 Source: RC3 *
NGC 558 (IC 117) Galaxy *
RA: 01h 27m 16.1s Dec: -01° 58' 13"
Mag: 15.3 (P) S.B.: --- B-V: --- Size: 0.4'x0.2' Class: E+? sp
P.A.: 116 Inclination: --- R.V.: +5018 Source: RC3 *
IC 120 Galaxy *
RA: 01h 28m 12.9s Dec: -01° 54' 55"
Mag: 15.2 (P) S.B.: --- B-V: --- Size: 0.8'x0.3' Class: S0^:
P.A.: 139 Inclination: --- R.V.: +4900 Source: RC3 *
NGC 564 is pointed at from the S by a mag 7 and a mag 9 *s from nearly 1/2 a field away. Small, 40-50" diameter, round halo growing broadly and mod to the centre without and zones to a small stellaring in the centre. Mod LSB. There is a very faint * just outside the W side of the halo. -60 is to the SW by 5'.
-60 is a very elong eg in PA 0 and points at a mag 11 * to its N about 4' away. Small Thin, tapered almost lens-shaped "tipped" halo 1.25' x 10" grows broadly and mod to the axis nr centre with a hint of a stellaring in the centre.-58 is to the SW by a few arc-mins as a tiny spot 20" dia of haze nr a 12th mag * to its W and has a very very faint *ar nucleus..
IC 120 is 5' to the SE of -64 and is a very faint and LSB slightly elong spot about 30" across with almost consistent SB and a very faint spot in the centre.
x185 27' , x247 20' TF
IC 127 Galaxy *
RA: 01h 29m 47.5s Dec: -06° 58' 48"
Mag: 14.5 S.B.: --- B-V: --- Size: 1.8'x0.4' Class: Sb: sp
P.A.: 119 Inclination: --- R.V.: --- Source: RC3 *
This eg is found by 1 field SW of the pairing of NGC 584 & 586. A very LSB edge on eg in about PA 120 that appears to grow out the side and to the WSW of a 12th mag *. Probably 1' x 10" growing broadly and weakly to the axis nr centre but no apparent core or nucleus.
x185 27'
NGC 599 (NGC 601) Arp 4 Mkn 1000 Galaxy *
RA: 01h 32m 53.8s Dec: -12° 11' 27"
Mag: 14.5 S.B.: --- B-V: --- Size: 1.8'x1.8' Class: SAB0- pec:
P.A.: 135 Inclination: --- R.V.: --- Source: RC3 *
NGC 589 Mkn 999 Galaxy *
RA: 01h 32m 39.8s Dec: -12° 02' 33"
Mag: 14.8 S.B.: --- B-V: --- Size: 1.2'x1.0' Class: (R)SB(r)0/a
P.A.: 154 Inclination: --- R.V.: +5177 Source: RC3 *
NGC 593 Galaxy *
RA: 01h 32m 20.8s Dec: -12° 21' 14"
Mag: 14.5 S.B.: --- B-V: --- Size: 1.1'x0.2' Class: SB(r)0^? sp
P.A.: 12 Inclination: --- R.V.: --- Source: RC3 *
-93 is found about 13' SE of a 7th mag *. Quite small faint and very elong in about PA 0, quite small, lengthened form 40" x 10" grows slightly to the axis nr centre with no apparent core, zones or nucleus.
-99 is about 20' E of the same mag 7 *. Round, fairly small and brighter than -93. There is a string of stars to its N leading to -89 10' to its NW. -99 is about 50" diameter, very LSB outer halo with a sizable core zone, maybe 30" dia, slightly brighter and contains a small weakly brighter spot at its centre.
-89 is 10 NW of -99 and is a small, 30" diameter round spot of haze with a small slightly brighter core zone but no real nucleus.
Pt 2 of 3 to follow ...