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Latest Website Update [12 Dec 2014] >> December Picture of the Month >> December Galaxy of the Month - Owen Brazell >> December Double Star of the Month - Bob Argyle >> Object of the Season Updated [Winter 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.

December 2014 - Picture of the Month

NGC 1566 ("Spanish Dancer" galaxy) in Dorado

NGC1566 with a Supernova - Image Courtesy of Steve Crouch

Image Courtesy of Steve Crouch, Canberra, Australia. Please click on the image for the high resolution version.

Steve's Observation Notes:

This magnitude 9.4 Seyfert galaxy is roughly 8.3' x 6.6' in size. It is the second brightest Seyfert galaxy after NGC 1068 (M77) and the brightest member of the Dorado galaxy group. The distance is not very accurately known and given as 38.4 million light years with an error of 18.6 million light years.

This image shows a supernova (discovered in September 2014) just to the right of the central nucleus. The luminance data (with the supernova) was taken on 12 November 2014 when it had started to fade. The discovery visual magnitude was given as 14.6.

Camera and Telescope
STL6303, STXL6303, 31.75cm and 36.8cm Ritchey Chretiens Focal Ratio F9
Exposure Details
RGB 100:100:100 all 1x1 with Astrodon filters using 31.75cm RC. Luminance 150 minutes with 36.8cm RC.

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

December 2014 - Double Star of the Month

The double stars being featured this month require apertures around the 30-cm mark. Both are close binaries with periods in excess of 200 years and both are slowly widening, but at the time of writing each pair is at or below 0".5 separation.

52 Arietis (03 05 26.69 +25 15 18.7) is also known as STF 346. At discovery this was an 0".7 pair and motion during the remainder of the century was slow but by the early 1930's the pair was out of reach of all telescopes and circling around each other at the rate of 1 degree per week.

Since then the companion has been heading out towards the discovery position but even now it is still a difficult pair. The ephemeris for 2014.6 gives 258 degs and 0".49, and the stars are almost equally bright, both being around 6.2 visual. The writer was just able to measure it for the first time last autumn with a 20-cm Cooke refractor and will attempt to get some confirming measures later this year.

The two stars are accompanied by a 10.8 at 5" distance which is physically attached to the system. Another star of mag 13.2 at 105" appears to have been found by Smyth in 1835 and is mentioned in the Cycle of Celestial Objects. Smyth gave the magnitudes of C and D as 15 and 13, no doubt reflecting the difficulty of seeing C rather close to the bright binary components.

At the turn of the nineteenth century, Walter F. Gale was an active amateur astronomer living in Paddington, New South Wales and found a few double stars with an 8.5-inch reflecting telecope made by George With. He published a short list of discoveries in Astronomische Nachrichten in 1896, consisting of 5 double stars and a ring planetary nebula (IC 5148 - the Spare Tyre Nebula). Two of the pairs turned to be already known so the WDS now contains but three of his double stars.

The second object on the list was a close pair in Reticulum now called GLE 1 (04 16 20.92 -60 56 54.8). The stars, whose visual magnitudes are 6.8 and 7.5, passed through periastron in 2002 and are now slowly widening again although the current separation (0".35 at 218 degs) does require at least 30-cm and a good night. This system also contains the star TT Ret which is an alpha CVn variable with small amplitude and period of 2.8 days.

Bob Argyle - Double Star Section Director

Object of the Season (Winter 2014/15)

NGC 4449 in Canes Venatici

Irregular galaxy NGC 4449 in Canes Venatici will be announced in DSO 166, and the results will be published in DSO 168.

NGC4449 - Image Courtesy of Hubble Space Telescope (HST) Please click on the image for a high resolution version taken by the Hubble Space Telescope (HST).

Position (2000)
12 28 11.0 +44 05 33 (CVn)
Visual magnitude
9.4 mag
Type
IBm
Size
5.5' x 3.6'
Distance
12.5 Mio. ly
Other Designations
I 213, h 1281, GC 3002, UGC 7592, CGCG 216-5, MCG 7-26-9, PGC 40973

Wolfgang Steinicke - Nebulae and Clusters Section Director

December 2014 - Galaxy of the Month

LGG 117 Group in Taurus

The constellation of Taurus is not traditionally where you look for galaxies but it does in fact contain quite a number of NGC galaxies. Most are quite faint but there are a number within range of medium to large telescopes (here I class this as in the 30-50cm class range) under typical UK skies (i.e. poor).

Our target this month is the small group of galaxies associated with NGC 1589. Known as LGG 117 from Garcia 1993 this small group consists of the NGC galaxies 1586,1587,1588 and 1589 along with a number of other UGC galaxies in the field. The total number of galaxies in the group is probably about 7. The finder chart shows some of these galaxies.

LGG 117 - Image Courtesy the Sloan Sky Survey

This image of the LGG 117 region was provided by the Sloan Sky Survey.

The brightest galaxies in this group are the interacting pair NGC 1587 and NGC 1588. First discovered by William Herschel in 1783 this pair will be a challenge. The brighter galaxy NGC 1587 is a peculiar elliptical and may be visible in 22cm however its companion NGC 1588 will be more of a challenge and will probably require at least 30-40 cm to separate out. The type of NGC 1588 may be questionable but is probably a peculiar elliptical as well. The deep images shown here from the Sloan Sky survey show that NGC 1587 appears to have shells and 1588 is clearly distorted. The distance to the pair has some variation but is about 40 Mpc or so. NGC 1587 itself is bright in X-rays.

NGC 1587 and 1588 - Image Courtesy the Sloan Sky Survey

This image of NGC 1587 and NGC 1588 was provided by the Sloan Sky Survey.

In the same medium power field is the edge on spiral galaxy NGC 1589. This was also discovered by William Herschel on the same night in December of 1783. NGC 1589 has had at least one supernova, the one in 2001 being discovered by Tom Boles and named as 2001eb. The distance to NGC 1589 is about 48 Mpc. The nucleus of NGC 1589 is classed as boxy and it will be unfortunately quite a challenge to see although Luginbuhl and Skiff report seeing it and 1587 with 15cm from a high dark site.

It would appear that both NGC 1589 and 1587 may belong to a class of AGN known as low luminosity AGN’s or LLAGN. Interestingly it is NGC 1589 and 1587 which are classified as a pair in the UZC catalogue.

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