Constellation of the Month - Lacerta

Michael Nelmes

This isn't one for the faint-hearted. With its brightest stars at 4th magnitude and its upper border culminating just 20 degrees above Canberra's north horizon, it's a bit of a trial just to find anything in it. I was not encouraged when consulting my initial source of basic information, Collins Gem Night Sky, to read that it contains "no objects of note to users of small telescopes". However we'll press on regardless, as this is an historic occasion. Lacerta is the only constellation, visible from Canberra, which has not previously been covered in our Constellation of the Month. Apart from that, three novae this century including the rapid rise of Nova Lacertae 1936 have given Lacerta some additional claims to fame.

Named for the lizard, it forms a small north-south zig-zag on the Milky Way's edge, to the lower left of the square of Pegasus (bordered also by Cepheus, Cygnus, Andromeda and Cassiopeia), so while there are a few open clusters, galaxies are few. To find your way around Lacerta, locate the two upper bright stars and follow the trail of half a dozen stars down to the horizon. I found binoculars useful in matching star fields to my charts before hunting objects down. Remember that atmospheric extinction at this altitude reduces star brightness considerably; and also that for the doubles, a small telescope may well out perform a larger one due to steadier images. Here's the selection (based on Hartung):

Struve 2894 (SAO72228; 22h 19m, 37deg 36.5min). Double star of magnitudes 6 and 8, separated by an easy 16 arcseconds. The primary is supposed to be yellow but I saw no colour. The secondary should be easily seen with a range of magnifications.

Struve 2906 (SAO72344; 22h 44m, 39deg 28.3min). Double star of magnitudes 7 and 11 separated by 4 arcseconds. Despite long searching, my 4.5-inch would not show the secondary, the brightness difference (a factor of 40) being too great at this close separation.

Struve 2942 (SAO72675; 22h 44.1m, 39deg 28.3min). Double star of magnitudes 6.2 and 8.4 separated by 3 arcseconds. As for 2906. The primary is noticeably orange.

NGC7243 (22h 15.3m, 49deg 53.3min). Open cluster. A dim conglomeration of stars 20 arcminutes across, more like a loose globular.

NGC7209 (22h 05.2m, 46deg 30min). Open cluster similar to 7243 but with a few brighter (foreground?) stars.

IC5217 (22h 24m, 50deg 59min). Planetary nebula. At magnitude 12.5, this was beyond the 4.5-inch. Size is 8 x 6 arcseconds.

I hope you get a chance to try for some of these.

Springtime Nights in Capricorn

Jenni Kay, FRAS

While the constellation of Capricorn covers a large area of sky I was surprised to discover it is relatively empty of NGC/IC type deep sky objects. The NGC objects, mostly galaxies, ranged in brightness from relatively bright to extremely faint as seen through the telescope. On the other hand, I found the IC galaxies to be very difficult to detect with most way too faint. Among the galaxies I targetted, there are also two globular clusters; one being the very impressive M30, the other is Pal 12. I found it was easy enough to navigate through Capricorn with numerous bright to relatively bright field stars marking a trail from one field to the next.

The following observations were made from my semi-rural home site at Lobethal, SA. Typically, the skies here have a naked eye magnitude of 6.1, with the seeing rated at Ant II-III. The telescope used was a 12.5" f/5 Newtonian.

M30 : Globular Cluster 21 40.4 -23 11

105X: bright and impressive - with a very bright, compressed central core region within a much extended soft outer halo. This outer halo is the glow from very faint, far reaching, unresolved outliers. Furthermore, the halo shows two prominent strands of stars in straight rows from the core with one trailing to the north, the other to the northwest. There are three 13 mag. stars to each row. 150X: Magnificent - the very bright core is mostly round with a size of 30", and the halo gradually fades out to the edges to an overall size of 4.0'. There are about twenty stars resolving in the halo at this power, and these are spread evenly across the cluster.

NGC 6907 (N6908 = NE arm): 20 25.1 -24 49

NGC 6912 : 20 26.9 -18 38 (13.6v; 1.2' x 0.9'; sb 13.5v; pa 82d.)

Very easy field to locate with the naked eye stars Pi and Omicron Cap nearby. 105X: somewhat difficult to spot being an extremely faint, hazy spot. The galaxy was glimpsed twice with averted vision. 150X: Improved view - with care, averted and patience the galaxy can be seen on several occasions with full confidence as very faint, round to slightly oval in shape, 40" in size, with a very low surface brightness. While the galaxy is quite elusive at 105X it is better seen at 150X. IC 1319 and IC 1321 lie nearby in the general field.

IC 1319 : 20 26.0 -18 30 (14.9mag; 0.8' x 0.5'.)

13'WNW of N6912. 105X: too faint. 150X: obvious enough but requires much care and averted vision - very faint, small, round, 25" in size, with a very smooth glow throughout.

IC 1321 : 20 28.2 -18 17 (15.2 P mag; 1.0' x 0.6'.)

27' NE of N6912. 105/150X : too faint to detect.

NGC 6924 : 20 33.2 -25 30 (12.4v; 1.7' x 1.4'; sb 13.2v; pa 131d.)

105X: obvious enough with care and averted vision - faint, relatively small, round to slightly oval, with a very smooth glow. 150X: improved view - there is a 13 mag. field star at the southern edge of the galaxy. The galaxy is relatively bright, small, a little oval, 30" x 20", major axis lies north to south. NGC 6939 lies to the ENE of the general field.

NGC 6936 : 20 35.9 -25 17 (12.8v; 1.6' x 1.0'; sb 13.2v' pa 4d.)

37.6' ENE of N6924. 105X: too faint. 150X: obvious enough, especially with averted vision - relatively faint, small, round, 25" in size, slightly brighter towards the centre to an almost stellar nucleus. The galaxy shows a smooth, even glow throughout.

NGC 6986 : 20 56.5 -18 34 (13.5v; 0.9' x 0.6'; sb 12.7'; pa 10d.)

105X: too faint. 150X: obvious enough - faint, very small, round, soft glow, 20" in size, with a smooth and even surface. The galaxy lies northwest of a bunching of five 12/13 mag. field stars which act as a good signpost to the galaxy.

NGC 7016 : 21 07.4 -25 30 (13.9v; 0.9' x 0.9'; sb 13.5v.)

First of three in a small group with N7017 and N7018. 105X: too faint. 150X: extremely faint, relatively small, round to a little oval in shape, with a size of 30", and now and then there seems to a stellar nucleus about 14 mag. The galaxy shows a low surface brightness. All three galaxies here require extra care to detect.

1.6' SE of N7016. 105X: too faint. 150X: extremely faint, round to a little oval, 30" in size, with a low surface brightness. This galaxy is slightly brighter to N7016.

NGC 7018 : 21 07.6 -25 28 (13.5v; 0.9' x 0.6'; sb 12.7v; pa 86d.)

3.6' NNE of N7017. 105X: too faint. 150X: obvious enough with care - extremely faint, relatively small, round, 30" in size, with a low surface brightness. This galaxy is the brightest of the trio.

NGC 7019 : 21 06.4 -24 25 (15.5v; 0.6' x 0.4'; sb 13.8v; pa 137d.)

105X: too faint. 150X: very difficult - extremely faint, strongly resembles a 14 .5 mag. star. Even after repeated efforts this galaxy still looks like a star only, usually there is a soft edge around such small galaxies but not this one, and I would not have picked this for a galaxy.

NGC 7030 : 21 11.2 -20 30 (13.7v; 0.8' x 0.6'; sb 12.8v; pa 23d.)

105X: too faint. 150X: obvious enough with averted vision and care - very faint, very small, round, hazy spot, 25" in size. The galaxy has a low surface brightness and a smooth glow throughout.

NGC 7035 / N7035A : 21 10.8 -23 08 (14.4v; 0.6' x 0.5'; sb 12.9v; pa 56d.)

105X: too faint. 150X: Requires care - appears little more than an extremely faint, fuzzy double star. The galaxy is 25" in size. IC 5088 and ESO 530-10 lie in the same field.

IC 5088 : 21 09.5 -22 55 (14.5 mag)

22.0' northwest of N7035. 105/150X: too faint to detect.

ESO 530-10 : 21 09.4 -22 53 (14.3 P mag; 1.2' x 1.0'.)

2.2' north of IC 5088 position. 105X : too faint. 150X: with much care and averted vision - extremely faint, relatively small, round, hazy glow. The galaxy is 35" in size with a very smooth surface.

NGC 7103 : 21 39.9 -22 28 (12.6v; 1.4' x 1.2'; sb 13.0v.)

105X: too faint. 150X: most obvious of two with N7104. The galaxy is very faint, relatively small, round to slightly oval, 40" in size, with a very smooth soft glow. This pair of galaxies are grouped closely with three IC galaxies: IC 398, IC 5122, and IC 5124, but I cannot detect anything of them - they are far too faint.

NGC 7104 : 21 40.1 -22 25 (14.4v; 0.6' x 0.5'; sb 12.9v.)

4.0' NNE of N7103. 150X: extremely faint, small, little oval, 30" in size, with a smooth and even glow throughout.

Pal 12 : Globular Cluster 21 46.6 -21 15

150X: Obvious enough with care, very faint, large, soft grainy glow, round, in shape, and 2.5' in diameter. The cluster lies against a dark, smooth background sky that makes it stand out well enough to detect. There is a neat little triangle of three stars to the SE of the cluster.

More on CAS History

Recollections by Neville Watson, with notes by Mike Nelmes

The History of the CAS series will be concluded next month. In the meantime, here are some recollections from one of our most senior members, Neville Watson, who in his eighties and retired now for twenty-five years, was still observing in recent times. Neville joined the Society in 1970 and has many fond memories of grazing occultation, eclipse and comet expeditions - typical, as he writes, of the life of an amateur astronomer and ones to which many of us will relate. "The field activities gave my telescope some testing times when being transported, over fences and across tall grass paddocks, in the dark, to some odd venues...".

On a grazing occultation seen from Goulburn: "About 6pm there was much movement in the car park when car boots were being opened and telescopes set up and inspected. I was in the motel's office when a traveller, while booking in, became intrigued by the unusual activity, and asked the proprietor what was going on. The answer came back loud and clear:

"'Oh, another bit of voodoo. A bunch of moonwatchers are having a night out. We had entomologists last week wanting all the outside lights left burning so they could catch moths. We get lots of nut cases like this all the time.' [Just as well the two visits didn't clash.]

"That night I was stationed on my own, on the northern side of the Goulburn Gaol and not far from the ominously dark walls. During the waiting time leading up to the graze I wondered if any of the guards on the wall could see me, and what they made of the crackpot down there with the telescope and radio set with a long aerial and tape recorder! I could have been a foil for a big breakout!

On observing Comet Kohoutek from O'Connor Ridge in 1973: "...The next interruption was a car creeping along Dryandra Street, and suddenly a strong light swept along the ridge towards me. The car stopped, and two dark figures got out and scrambled up the hill. Two policemen in uniform. The opening shot was from the heftier of the two: 'Well, what ya doing?" I could hardly find an answer to that one: there, standing in front of me, was a telescope, fully set up and pointing to the sky.

I thought it was obvious what I was doing. But I knew also a smart reply would get me nowhere, and in any case his question was to hold my attention while the second constable searched my car, including the boot, without even a hint of his intentions.

"It took the best part of fifteen minutes to get close to convincing them I was looking for a comet, but because I hadn't found the comet I had no evidence. And the name Kohoutek meant nothing to them, even though the media had carried feature articles of it for about a week. Fortunately Saturn had risen, and was a beautiful sight in the dark sky. So I asked the sentinels of the night if they would like to take a look through the telescope at it. I'm sure it was an anticlimax for them to realise I was innocent of any crime, especially as they would have to fill out a report about their visit to the ridge. But, no doubt it would be a good talking point back at their station or at home over the breakfast table. I packed up the telescope and drove home completely frustrated."

After a ten year lull in viewing (precipitated by more frustration at having to sit a gemology exam at the precise time of the 1976 total solar eclipse), Neville writes, "the great expectations of Halley's Comet generated by the media and others revived my dormant spirits, and in 1986 I purchased a 150 mm reflector. For the next 14 years I pursued star gazing at my leisure, and watched the trees grow in my neighbourhood to the point where observing has become limited and hazardous."

He braved the elements for satisfying views of Hyakutake (1996) and, from the Jamison Centre carpark, Hale-Bopp ("becoming more and more conscious of the possibility of being mugged" before a queue of intrigued passers-by started forming).

Neville recently advertised his telescope for long-term loan to a worthy young CAS member.