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

Where have the links to all the publications and their indices gone? They're all still available via the Our Publications link in the menu above. The details of our 2015 Annual Meeting have moved to a dedicated page accessible via the self-explanatory Annual Meeting 2015 link in the menu above. Keep an eye on it for updates.

November 2014 - Picture of the Month

NGC 1333 in Perseus

This image is provided with the kind permission of Warren A. Keller and Jimmy Walker. Please click on the image to be taken to Warren's website for a higher resolution version.

In Warren's words

NGC 1333 is the bright nebular complex at center. A mere 1,000 ly from Earth, it consists of blue reflection nebulosity and many firey-red, Herbig-Haro objects which indicate active star forming regions. As such, NGC 1333 contains hundreds of stars less than one million years old- mere babies in astronomical terms. The associated Perseus OB2 molecular dust cloud complex seems to go on forever! Two other blue reflection nebulae can be seen near bottom and at 3 o'clock. Another lovely area of interest is the yellowish nebula surrounding the star HD 21110 above 7 o'clock.

This is the first collaboration with my friend and imager extraordinaire Jimmy Walker whom I am extremely grateful to for data acquisition.

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

November 2014 - Double Star of the Month

10 Arietis (=STF 208, 02 03 39.26 +25 56 07.6) is a marginally naked-eye star at the preceding end of a string of similar stars some 2.5 degrees north of alpha Arietis. Found by F G W Struve in 1821, when the separation was 2", the motion of the companion over the next 80 years appeared more or less linear but it became progressively more curved as the pair closed to 1". The companion then made a closest approach at 0".3 in 1920 or so and since then has widened and can be found at 347 degs, 1".49 in 2014.8. The currently accepted period is 325 years but this could well be an underestimate as nothing is known about the motion at apastron. The pair should be divided in 15-cm but a good night is needed because the magnitudes of the stars are 5.8 and 7.8. A 13.5 mag. can be glimpsed 95" distant in PA 150 degs.

kappa Tucanae (01 25 45.50 -68 52 34.5) is located about 5 degrees north following the Small Magellanic Cloud and Burnham's Handbook spends a lot of time on the latter but only notes in passing the former which is a splendid object for both binoculars and telescope. For the binocular user there is a mag 7.8 star which is 319" from the mag 5.00 primary. John Herschel found A to be a fine pair (HJ 3423, mags 5.0 and 7.7) - 'very beautiful' was his verdict. E J Hartung gives the colours as yellow and orange. Two measures at Feldhausen yielded separations of 2" and 2.5" and a mean position angle of 11.7 degrees. Recent measures in 2009 show that the separation has doubled to 4".8 and the position angle is now 319 degs. This is a binary system with a period of about 850 years.

In 1895 Robert Innes found that the distant 7.8 mag star was also double but much more equal in brightness (7.8 and 8.4) and also a binary of fairly short period. He was using a reflecting telescope owned by Mr. F. Dixon Edmonds, an early member of the BAA, and in presenting his list of 16 new pairs Innes said that the telescope had enabled the 'discovery of more new double stars than all the rest of the silver-on-glass reflectors ever made'. I 27 CD revolves every 85.2 years in a circular orbit only slightly tilted to the line of sight so the separation ranges between 0".9 an 1".1 and the angular motion is a fairly constant 4 degrees or so. Innes also noted that both AB and CD have similar proper motions so this is likely a quadruple system.

Bob Argyle - Double Star Section Director

November 2014 - Galaxy of the Month

NGC 507 Group in Pisces

The NGC 507 group is the single richest group of galaxies in Pisces containing 9 NGC galaxies brighter than 15th magnitude. There are also a number of galaxies listed in the IC here as well. The accompanying chart also shows the profusion of fainter background galaxies that are probably not part of the group. The group is part of the Perseus-Pisces super cluster confusingly it is also known as the Pisces cluster along with the NGC 383 cluster. The main cluster galaxies were discovered by William Herschel in 1784.

NGC 507 - Image Courtesy the Sloan Sky Survey

This image of the NGC 507 region was provided by the Sloan Sky Survey.

The largest and brightest galaxy in the group, NGC 507 was discovered to have faint concentric shells by Halton Arp when looking at plates taken by the 200". He subsequently added it as Arp 299 in his catalogue of peculiar galaxies. These shells are now thought to be the product of ancient mergers. NGC 507 is also an AGN and seems to have radio lobes associated with it.

NGC 508 is not part of Arp 229 despite some sources suggesting it is. The description by Arp is quite clear what Arp 229 is. Although they are quite close in angular terms it is not clear that NGC 508 is actually physically associated with NGC 507.

NGC 507 - Image Courtesy the Sloan Sky Survey

This image of the NGC 499 region was provided by the Sloan Sky Survey.

The group does show a number of small sub-structures in its central core which suggests that it may still be in the process of accreting other smaller groups of galaxies and has not yet reached its final state. NGC 499 appears to be at the centre of a second peak in the X-Ray halo and may be the central galaxy of another group merging with the NGC 507 group. Unfortunately it is not possible to say which way NGC 499 is moving.

The main part of the group is in the form of a chain but there are a number of galaxies off the side of this chain as well. The group would appear to be at a distance of 63 Mpc and forms part of the main filamentary ridge of the Perseus-Pisces super cluster that also contains the Abell clusters 262, 347 and 426.

NGC 515 and 517 - Image Courtesy the Sloan Sky Survey

This image of region around NGC 515 and NGC 517 was provided by the Sloan Sky Survey.

Visually this is a stunning group. The brightest members should be visible in a 22cm telescope but it is with larger telescopes that the true beauty and number of galaxies in the field is really shown. The whole group will fit in the medium power field using a hyperwide (100 degree AFOV) eyepiece.

Surprisingly there are no decent scale amateur images of this bright group so the images accompanying this piece are all from the Sloan digital sky survey. Perhaps a challenge for our members who have CCD imagers.

Owen Brazell - Galaxy Section Director

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.

Two Nights Observing in August by David Reynolds.

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.

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