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Latest Website Update [2 October 2014] >> October 2014 Galaxy of the Month >> October 2014 Double Star of the Month - Bob Argyle >> Object of the Season Updated [Autumn 2014] - Wolfgang Steinicke

If your favourite image or observation has disappeared from the home page, don't worry. They're all archived for posterity in the new Observations section which has earned a link in the menu above.

Hello from the new Website Administrator

I'm James Whinfrey and I've taken over the management of this website from Tim Walker, who retired from this post after many years of hard work on this site. Thank you Tim.

As the new guy, I'd appreciate any comments and suggestions about what you'd like to see on this website in the future. Please let me know if you have any problems.

Webb Deep Sky Society 2015 Annual Meeting

This will take place on Saturday June 20 at the Institute of Astronomy, Cambridge. The meeting will follow the usual format.

Three speakers confirmed so far are Wolfgang Steinicke (Germany) with "John Herschel’s Cape Observations", Magda Streicher (South Africa) with "Treasures of the Southern Sky", and Andrew Crumey, who will talk to us about "Modelling the visibility of deep sky objects".

Object of the Season (Autumn 2014)

M 35, NGC 2158 and IC2157 in Gemini

The chain of open clusters M 35, NGC 2158 and IC2157 in Gemini will be announced in DSO 165, and the results will be published in DSO 167.

M35/NGC2158/IC2157 in Gemini

Please click on the image for a high resolution version.

Data for the autumn 2014 objects of the season.
Data M 35 NGC 2158 IC 2157
Position (2000) 06 09.0 +24 21 (Gem) 06 07 25.6 +24 05 46 (Gem) 06 04 49.8 +24 03 21 (Gem)
Visual magnitude 5.1 8.6 8.4
Type III2m II3r III2p
Size 25' 5' 5'
Distance 2800 ly 16000 ly 6700 ly
Other designations h 377, GC 1360, NGC 2168, Melotte 41, Collinder 82, Lund 207, OCL 466 VI 17, h 375, GC 1351, Melotte 40, Collinder 81, Lund 206, Raab 30, OCL 468 OCL 465, Collinder 80, Trumpler 4

Wolfgang Steinicke - Nebulae and Clusters Section Director

October 2014 - Double Star of the Month

About 2 degrees north of iota Cephei can be found the pair STF2947 (22 49 00.68 +68 34 12.2). This neat 4".6 pair can be well seen in 15-cm and the magnitudes are 6.9 and 7.2. Sissy Haas notes that iota is golden colour and STF2947 is a pair of yellowish-peach stars. Hipparcos does not appear to have observed this pair but it does appear in the 1952 Yale Catalogue of Parallax where the distance is given as 120 light years but with an uncertainty of 20%. A third star of magnitude 12.5 can be found at 208 degrees and 121" but it does not share the space motion of the close pair. About two degrees south is STF2948 (7.3, 8.6, 4 degs, 2".6))

Theta Gruis (23 06 52.77 -43 31 17.2) is the brighter component of the very wide pair SHY 366. The nomenclature refers to Shaya and Olling who in 2010 made a study of wide pairs in the Hipparcos catalogue for which the proper motions were very similar. In the case of Theta Gruis they concluded that the likelihood that A and C (mags 4.5 and 7.8, 292 degs, 159") were physical was 100%. The distances to A and C are respectively 131.9 and 130.4 light years. Jacob then discovered that A itself was a close pair with star B of magnitude 6.6, being found at 114 degrees and 1".5 in 2009. William Stephen Jacob was an Army engineer with a deep interest in astronomy an during secondment on duty in India in the 1840s managed to make some observations of double stars. He used the 6.3-inch Lerebours refractor at Madras to make some micrometric measurements and also discovered a number of new pairs. The WDS contains 24 pairs bearing his discovery number which also includes the binary JC 8 and the Antares lookalike-pair 21 Sgr = JC 6 (see the column for Sep 2008).

Bob Argyle - Double Star Section Director

October 2014 - Galaxy of the Month

NGC 6951 in Cepheus

NGC6591 - The image is courtesy of Martin Winter and Warren Keller.

This image was provided by Martin Winter and Warren Keller. Please click on it for a high resolution version.

In 1877 Jerome Coggia discovered a nebula in Cepheus that was given the name NGC 6952. Later Lewis Swift independently found a nebula nearby in 1885. Denning later showed that these were one and the same object but Coggia had a positional error of 20’. The designation NGC 6952 was later dropped and Dreyer issued a correction in the IC2.

The galaxy is classified as SAB(rs)bc, a barred spiral galaxy. Its bright core also suggests it is a Seyfert galaxy (a mild active galactic nucleus or AGN). It would appear to be a type two Seyfert galaxy. NGC 6951 lies about 65 million light years away and has been home to two recent supernova in 1999el and 2000E. The galaxies location also means that it is involved with a lot of galactic cirrus as this deep image shows. An even deeper image can be found at the Capella Observatory website. A wide field view of the cirrus can be found on Oleg Bryzgalov's astrophoto website. The galaxy is interesting because it is showing both strong star formation activity and an active core. As the galaxy is an isolated system it is not clear what has triggered the current round of star formation. The galaxy appears to have a circumnuclear ring and the gas flowing through the bar appears to stall here and provide the material for massive star formation. This is not unlike what seems to be happening in our galaxy on a smaller scale. The ring appears to be about 1.5 billion years old and seem to have been forming stars for most of that time.

Visually the galaxy is going to be a difficult target. From typical UK skies I think that at least 30cm+ aperture will be needed. Through a large telescope the galaxy shows a bright core and a fainter envelope. The envelope is definitely elliptical in shape. Smaller instruments may well just show the core.

Owen Brazell - Galaxy Section Director

October 2014 - Picture of the Month

NGC 6946 The Fireworks Galaxy in Cepheus

NGC6946 - Image Courtesy of David Davies

Image Courtesy of David Davies, Cambridge, UK. Please click on the image for the high resolution version.

For more images from David please visit his Flickr Photostream.

Last Thursday, 2 October, was a particular clear, cold night with reasonable transparency. A bright first quarter moon did, however, restrict what one could see.

I had a short-list of objects I could attempt to image in Cephus and Cygnus and settled on NGC 6946, The Fireworks Galaxy, Arp 29, Caldwell 12. This is my first view of this galaxy. We view it through plane of our own galaxy and it is significantly dimmed by the intervening stars and dust.

The data defining the spiral arms were only a few hundred ADUs above the bright sky background given by the moon. For a while I wondered if I would achieve a presentable image, especially when I discovered that the 100 minutes of luminance data I had gathered were spoiled by a finger print on the luminance filter. I must have been really clumsy when I changed the filter wheel in the camera.

So this image is essentially RGB only, comprising 45 minutes each of RGB in 5 minute subs. I constructed a luminance layer from the composite RGB image and separately processed that to make a final LRGB image.

  • Telescope is a Skywatcher Quattro 254 mm F/4 Newtonian with a Tele Vue Parcorr.
  • Camera is a QSI 583 with a Lodestar off axis guide camera guiding via PHD2.
  • Mount is a Skywatcher NEQ6 controlled via EQMOD.
  • Image capture was with Nebulosity.
  • Automatic focussing was with Scopefocus working with Nebulosity. Image stacking was with Deep Sky Stacker and processing with Pixinsight and Photoshop.

This is a crop from the final image.

NGC 281: the Pacman Nebula

NGC 281: the Pacman Nebula in Halpha - Image Courtesy of Paul A Brierley Image Courtesy of Paul A Brierley, East Cheshire, UK. Please click on the image for the high resolution version.

I hope you are all enjoying this pre equinox sunshine.

When the skies where I live, in East Cheshire, finally cleared least night. I was able to take 15 minute exposures of the "Pacman nebula" that is currently visible high in the Autumn sky near the star Schedar, Alpha Cassiopeiae.

I used the usual equipment. And took 1¾ hours of image data, all 15 minutes through a Baader 7nm Ha filter.

The images were stacked in DSS and post-processed in Startools and CS2. CCD and mount control via SGPro and PHD 1.

Current Deep-Sky Observer - DSO165

DSO 165 Cover

In this issue

Observing the Helix Nebula - NGC 7293 by Stewart Moore.

Deep-Sky Observer Commentary by Ron Morales.

Observing Some Galaxies in Vela by Ronald J Morales.

Herschel 400 Observing Guide by Stephen J O’Meara reviewed by Andrew Robertson.

Southern Gems by Stephen J O’Meara reviewed by Carl Knight.

Observing Double Stars in Summer by Peter J T Morris.

Object of the Season: Globular Cluster NGC 5466 in Bootes by Wolfgang Steinicke.

Editorial

Recently we had a resignation letter that cast a number of aspersions on the society and in particular on its policy towards being up-to-date in terms of observing. The suggestion was that the society basically was only interested in a boys toys competition with my Dobsonian is bigger than yours. This I believe was triggered by comments about the Caldwell list and the BAA DSS in the last editorial. It is probably time then to again talk about what we will and won’t publish. There are many magazines out there that cater for CCD observers with detailed articles on how to process your images. That is not something I am interested in. I am however interested in articles that use CCD images to tell a story or describe a project. Unfortunately very few articles of this type are written which is a shame. The focus seems to be on how to process images not what the images are of. If members would like to write an article about projects that they are doing with their CCD equipment then I would be delighted to publish them and now we have the PDF version of the magazine where we can publish full colour then we can show these images to their best. The imaging world is also getting very impressive in terms of equipment and image quality.

The 2014 AGM was well attended but it was disappointing to note that nobody came forward to act as the society webmaster. This is the reason that the website has had minimal updates for some time. We do now have a new webmaster in James Whinfrey and hopefully we can get the website moving again. I hope that you will support him as you supported Tim and we can continue to have the dynamic website that we had before. It is worth noting that the society now has some new publications for sale. Alvin Huey has kindly allowed us to print some of his fine observing guides so you can now get The Arp Guide, The Hickson Guide and the Abell Planetary Nebula Guide via the society. We have also printed the Deep Sky Forum Object of the Week for 2012 and 2013. If you are interested in copies please contact Steve Rayner or see us at a star party or astronomy show.

guides covering the Herschel 400, Herschel 400 II and Herschel 400 III. Hopefully we will also soon have the second edition of the introduction to Visual Observing out. This has taken longer than hoped to get out because of issues with illustrations.

We are now getting back into the observing season although I did spend some of the summer in the high arctic looking for Polar bears I have had the 15-inch out a few times but an accident with the garage door has trapped the larger telescope inside. Hopefully it will be rescued in time for the star party season to get underway. I must admit though to spending a lot of that time looking for moving fuzzy objects.

In terms of new technology it has been an interesting summer with a number of new books on deep sky coming out. Hopefully we will have a review of some of them in a forthcoming edition of DSO. These include The Messier Objects 2nd Edition by Stephen O’Meara (CUP) , The Concise Catalog Of Deep Sky Objects by Warren Findlay (Springer), Choosing and using Astronomical Filters by Martin Griffith (Springer) (Mostly CCD imaging). Forthcoming presumably by Oculum will be an English edition of the Interstellarum Atlas in both Premium and Standard edition. I have the German Premium edition and it is very good. Rumours suggest an October timeframe. In equipment terms not a lot seems to have happened. The promised review of the Explore Scientific 9mm 120 has been put off until DSO 166.

We do have a few articles in the bank for DSO 166 but it would be nice to have a few more so I can start thinking about the balance for that and DSO 167.

Those interested in the mechanics of deep sky observing might want to look at Andrew Crumey’s paper on human vision. I believe it was considered somewhat controversial by the referees and I do query some of his data on what William Herschel could and could not see, especially in regard to Wolfgang’s presentation at the 2013 AGM.

Owen Brazell - Editor of The Deep-Sky Observer

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 preparing for a relaunch of the website with version 2.1 in early 2015, so keep an eye on it.

DSO162 - Erratum

It has been brought to my attention that there are a number of transcription errors in the Ron J. Morales article on the 'NGC 1550 Region in Taurus'. I have attached a corrected version of this article. Most of these articles are scanned and the OCR software sometimes has issues with the material. I apologise for this production error. Owen Brazell (DSO Editor).

Warning - Bank Charges

If you intend to purchase a DVD and/or publication from The Webb Deep-Sky Society via bank transfer and you are outside the UK then please check what the bank will charge for this transaction. We know of a least one bank abroad that charged 90% of the cost of the item to use their services.

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