Bulletin Board

Latest Website Update [1 Nov 2015] New Galaxies and Double Stars of the Month for November >> A new Object of the Season: NGC 1501 in Camelopardalis

We have a date for the 2016 Annual Meeting: 18 June 2016.

The news section contains more detailed items. I try to post items that may be of interest to members there. If you have suggestions, please contact me.

Professor Gerry Gilmore, whom many will remember gave such a stimulating and interesting talk on the GAIA mission at the Annual Meeting in 2014, invites potential users of the GAIA dataset to submit suggestions for apps which might be used to help with interpretation or presentation of the data.

November 2015 - Picture of the Month

This month I've gone for some objects that I'm unlikely to see through a telescope. It's time to visit the southern skies again with both colour and narrowband images of a star cluster and its nebula.

The Tarantula Nebula in Dorado

The Tarantula Nebula in Hydrogen Alpha - Image Courtesy of Steve Crouch

I'm a bit of a sucker for hydrogen alpha and the detail it seems to draw out of certain nebulous regions. This image by Steve Crouch from Australia brings out the extent of this gas cloud beautifully.

On the other hand full RGB colour can be impressive too. Which do you prefer?

An RGB image of the Tarantula Nebula - Image Courtesy of Steve Crouch

Clicking on either image will open a new window with a larger version from Steve's site.

Steve's Description

This huge emission nebula complex in the Large Magellanic Cloud would more than cover the whole constellation of Orion if placed at the position of the Orion Nebula. It is visible with the naked eye as a hazy spot.

Camera and Telescope
STXL6303 and 36.8 cm Ritchey Chretien
Exposure Details
Ha=195m, OIII=210m, SII=225m, R=G=B=30m all unbinned. Ha, OIII and SII combined as luminance over RGB layer.

For more images from Steve please visit his CCD Astronomical Images from Canberra website.

November 2015 - Double Star of the Month

56 And (01 56 09.23 +37 15 06.5) is a very wide pair of stars which can be found 5 degrees south and a little preceding that spectacle of the autumn sky, gamma Andromedae.

It is notable for the colours of the stars involved.

Here we have a K0 giant (A) and an M0 giant (B) within 200" of each other but actually not associated at all. The M star is about 3 times further away than the other according to Hipparcos.

Although the WDS gives visual magnitudes of 5.7 and 6.0, historical reports sometimes put star B as the brighter of the two - it is likely that either or both stars are liable to some small variation in brightness of a size such as to blur the difference between the two altogether.

Burnham, who would have been interested in this system because of the large proper motion of A (0".2 per year), found a faint companion of mag 11.9 at 18" and 77 degrees from A.

Also nearby (two-thirds of a degree preceding and a little north, according to the discoverer William Herschel), is STF 179, containing stars of magnitudes 7.6 and 8.1 separated by 3".5, and the open cluster NGC 752 is less than a degree north following.

Bernhard Hildebrande Dawson was an Argentine astronomer who was born in Kansas City in 1891 and who worked initially at La Plata Observatory in Argentina. He was perhaps best known as the discoverer of Nova Puppis 1942.

His double star discoveries are denoted by a small greek delta and number 31 is perhaps his most interesting find - a visual pair with a period of 4.56 years.

He started using the 17-inch refractor at La Plata in 1912 to pursue a programme of re-measurement of the John Herschel pairs. The first star in his catalogue (DAW 1 at 02 27 57.34 -58 08 22.3) was found in 1916 and sits in a rather blank area of sky in Horologium about 13 degrees following the first magnitude Achernar. This is a triple system with the two widest components (17" apart) being found by Sir John Herschel in South Africa.

In 1916 Dawson divided A and found a separation of 0".8. The current value is 1".2 so assuming it is still widening this would explain why Herschel did not see it during his sweeps.

The WDS gives A and B as 8.0 and 8.5 whilst C is 9.6. The range of position angle of AB is close to 180 degrees, a sign that the magnitudes of the two stars must be close enough to cause uncertainty about the quadrant in which B sits.

Ross Gould from Australia using a 40-cm sees A as a bright yellow star whilst x140 will show the Dawson companion.

Bob Argyle - Double Star Section Director

November 2015 - Galaxy of the Month

NGC 1060 Group in Triangulum

This interactive image of the NGC 1060 group was provided by the Sloan Sky Survey using Aladin Sky Atlas. We've also provided a finder chart for the group too.

This interesting group of galaxies centred on the elliptical galaxy NGC 1060 does not appear in any of the standard references such as Webb DSOH Vol 5, L&S or NSOG.

The two brighter galaxies in the group 1060 and 1066 were discovered by William Herschel in 1784. The others in the group were discovered by Lord Rosse’s observers using the 72” Leviathan except for NGC 1067 which was discovered by John Herschel in 1829.

The physical group which is classified as WBL 085 consists of the 7 galaxies: - NGC 1057, NGC 1060, NGC 1061, UGC 2201, NGC 1066 and NGC 1067 and an unknown.

NGC 1060 is classified as an S0- (a lenticular galaxy). NGC 1066 which is the other large and brightish galaxy in the group is classified as an elliptical but also as a type 2 Seyfert, i.e. it has an active nucleus.

This makes the groups contents slightly interesting as there are two lenticulars, one elliptical, three spirals, and irregular. There are a number of other galaxies scattered about this field but their faintness suggests that they are much further away than NGC 1060.

The only other galaxy of interest here is the face on spiral UGC 2174. According the Lyon catalogue of local groups it is associated with the NGC 1060 group which is classified here as LGG 072. This would then be the seventh member of the group.

Some programs associate NGC 1062 with UGC 2201 but historically this is incorrect as the Birr observers observation which was later tabulated as NGC 1062 is in fact a star according to Corwin.

This is one of the areas where I find computer star charting programs interesting in terms of their primary identifications. Megastar 5 for instance labels these galaxies by their UGC labels by default whereas SkyTools labels them using their designations from the MCG catalogue. Both are correct of course but the consistency of choice obviously depends on where one comes from.

So the interesting question here becomes what aperture do you need to see all the galaxies in the group. SkyTools suggests that under the dark of new moon I should be able to see all of them with the 22”, even the face on UGC 2174 whereas with the 15” I should only be able to see four of them.

An interesting challenge should we get dark skies in the next new moon window. Note that on the accompanying Megastar chart UGC 2201 is incorrectly labelled as NGC 1062 and on the image the DSS does not cover UGC 2174.

Owen Brazell - Galaxy Section Director

Object of the Season (Autumn 2015)

Planetary nebula NGC 1501 in Camelopardalis

Planetary nebula NGC 1501 in Camelopardalis will be announced in DSO 169, and the results will be published in DSO 171.

The optical galaxy pair NGC 1 and NGC 2 in Pegasus: NGC 1 is the northern object - Image Courtesy of Sloan Digital Sky Survey (SDSS) This image was supplied by the Hubble Space Telescope (HST). Credit: ESA/Hubble & NASA Acknowledgement: Marc Canale

NGC 1501

Position (2000)
4 06 59.4 +60 55 17 (Cam)
Visual magnitude
11.5 mag
Central star
14.4 mag (CH Cam)
4200 ly
Other Designations
IV 53, GC 801, PK 144+6.1, ARO 44, VV 16

Wolfgang Steinicke - Nebulae and Clusters Section Director

Deep-Sky Observer (DSO) No 153 - Free Sample

DSO153 Cover

This free journal is DSO 153 from 2010. You can download it as a PDF file onto your computer by right clicking the link below and choosing either 'Save Target As' or 'Save Link As'...

Download DSO 153 (2MB PDF file)

Clear Skies Observing Guides (CSOG)

Courtesy of Victor van Wulfen.

Clear Skies Observing Guides Banner

Webb Deep-Sky Society member Victor van Wulfen produces the CSOG. He's recently relaunched the website with version 2.1, so now would be a good time to take a look.

The Brightest Planetary Nebulae Observing Atlas - 2nd Edition

Massimo Zecchin has just completed the 2nd Edition of an atlas of planetary nebulae observed with small apertures and from suburban locations, entitled: "The Brightest Planetary Nebulae Observing Atlas".

Massimo has kindly made the atlas is freely available in two versions, Black (for display) and White (printer friendly with the images in negative).

The 2nd Edition contains:

  • Six additional objects.
  • Data of visual magnitude, central star magnitude and object size from the Strasbourg-ESO Catalogue of Galactic Planetary Nebulae (SEC catalogue) and in a few cases from the Saguaro Astronomy Club database (SAC catalogue).
  • Calculated surficial brightness for any object (in magnitude per square arcsec).
  • Six additionaltables showing the objects sorted by magnitude, surficial brightness, size, central star mag, constellation and declination.
  • A general position map.

Either version of the atlas can be downloaded as a PDF file onto your computer by right clicking the respective image above and choosing either Save Target As or Save Link As...

Please note that the Black version is 14MB and the White version 10MB