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Latest Website Update [1 October 2014] >> October 2014 Double Star of the Month - Bob Argyle >> September 2014 Galaxy of the Month >> 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.

Two speakers confirmed so far are Wolfgang Steinicke (Germany) and Magda Streicher (South Africa).

September 2014 - Picture of the Month

NGC 6888 The Crescent Nebula in Cygnus

NGC6888 - 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.

It's been a little while since I've shared anything from the deep sky. I managed to be away during several of the clear nights we've had recently.

My observatory was completed just over one year ago and the first object I observed from it was the Crescent Nebula. It seemed fitting to return to it this year and see if I could do any better.

So I've spent several nights during August (17, 28 and 31) gathering narrow band data on the Crescent Nebula and further time learning how to process narrow band images. The attached is the result.

I now have the benefit of automatic focussing which is helping I think by enabling me to refocus by remote control during the night. I'm using a Lakeside focus motor and the Scopefocus application from Kevin Sipprell in the US that works with my image capture software, Nebulosity.

Viewing conditions were almost universally poor with poor transparency and high thin cloud. This image comprises 100 minutes of H-alpha and 200 minutes of OIII data in 20 minute subs, five hours in total, captured with a 254mm Newtonian and QSI 583 camera equipped with 3nm Astrodon filters.

Processing was done in Pixinsight where H-alpha was assigned to red, OIII to blue and a synthetic green was generated using 85% blue and 15% red. I did try to combine the H-alpha and OIII with a normal green image and the result was just awful.

I'm fascinated by this object. The great bubbles of OIII extend well beyond the normally visible object and are also evident throughout its internal structure.

I'm continuing to capture RGB data and it would be interesting to see if I can combine the RGB and narrow band data in the future.

September 2014 - Galaxy of the Month

NGC 7339 in Pegasus

NGC7339 - Image Courtesy the Sloan Sky Survey

This image was provided by the Sloan Sky Survey and this finder chart was produced using Megastar 5.

NGC 7332 and NGC 7339 are an isolated bound pair of galaxies about 67 million light years away. NGC 7332 is lenticular galaxy with a boxy nucleus. Lenticular galaxies have a light profile that makes them look like spiral galaxies but they have no gas and new stars. They are usually found in large galaxy clusters where it is believed that the gas is stripped out by ram pressure as the galaxy moves through the intra-cluster medium. It is relatively unusual to see them in isolated situations like this.

NGC 7339 is an edge on spiral that is unusually blue. The pair form number 57 0 in the catalogue of double galaxies by Karachentsev. Although NGC 7332 and 7339 appear to be a dynamically interacting pair there are no signs of tidal distortions in the system so the orbit is currently fairly wide. Deep radio observations of the system also show no evidence of tidal interactions although they have turned up some new dwarf galaxies associated with the pair. They do however show a stream of gas in NGC 73339 which could be the remains of a merger event which could account for the current star formation episode in it. Recent surveys looking for globular clusters suggest that both galaxies have a small number ~175 for NGC 7332 and perhaps 75 for NGC 7339. NGC 7339 was also home to supernova 1989L. Both the galaxies were discovered by William Herschel in 1784. NGC 7332 is catalogued as S0(pec) because of the box like shape of its nucleus. The box could be evidence for a bar in the galaxy. Unusually for an S0 type galaxy NGC 7332 does show evidence for a large amount of ionized gas so it maybe a young version of this type. NGC 7339 is probably an Sbc type spiral but is features are fairly low contrast.

Both these galaxies are relatively bright and should be visible in telescopes of 20cm or above aperture from typical UK skies. The galaxies are an interesting pair because they are at right angles to each other. It should be noted that NGC 7339 is the fainter of the pair whne seen visually. It may be possible with larger telescopes to make out the box like shape. Of the nucleus of NGC 7332. They make a nice pair to warm up with before going are more challenging targets.

Owen Brazell - Galaxy 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

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.

Object of the Season - Summer 2014 & Autumn 2014

The Webb Deep-Sky Society Nebulae & Clusters Section Director Wolfgang Steinicke has requested observations for the following deep-sky objects. Please click on images for high resolution versions.

Object of the Season (Summer 2014)

Planetary nebula NGC 40 in Cepheus was announced in DSO 164, and the results will be published in DSO 166.

NGC40 - Image Courtesy of Capella Observatory: Stefan Binnewies, Rainer Sparenberg, Josef Pöpsel Our thanks to Stefan Binnewies, Rainer Sparenberg and Josef Pöpsel of the Capella Observatory for the use of this image of NGC 40.

Object of the Season (Autumn 2014)

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.

The complete schedule, including further objects, is published in the Deep Sky Observer (DSO).

Observations should be sent to Wolfgang Steinicke , Gottenheimerstr. 18, D-79224 Umkirch, Germany.

Current Deep-Sky Observer - DSO164

DSO 164 Cover

In this issue

AGM Report 2013 by Bob Argyle.

Webb Society Accounts for the Year to 31st March 2013 by Steve Rayner.

The Teenage Deep-Sky Wonder by Mark Bratton.

Next Object of the Season: Planetary Nebula NGC 40 by Wolfgang Steinicke.

Hickson 22 by Ronald J Morales.

Object of the Season: Bipolar Nebula NGC 2163 in Orion by Wolfgang Steinicke.

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