Imaging from the worst place on Earth? Possibly!

Welcome to my image blog from Lancashire, UK. Living in Lancashire does make imaging a challenge. Our incessant damp cloudy weather is legendary and coupled with light pollution probably as bright as can be found anywhere (I am 15 miles NW of the centre of Manchester) makes for testing times! Add to that flight path one with constant aeroplanes, which is why it has been suggested as possibly the worst place on Earth for imaging.

But there is some good news. With modern light pollution filters we can still produce excellent results - at least when the clouds clear - but of course it's not easy. It would be so much simpler to log onto a robotic rent-a-scope and let them take the image for us. But if you are up for the challenge and the achievement of taking your own images, with your own equipment, in your own back garden, then I hope the following offers some encouragement. Yes it's difficult but we can do it.

I often shoot the luminance and the colour simultaneously - there are not enough clear spells to allow the luxury of shooting separately. Shooting LRGB with one telescope would take years! So two telescopes and two cameras was the obvious solution . Also necessary is having a dome slot wide enough for both to have a clear line of sight. The luminance is usually taken with the RCOS + Apogee Alta and the colour with the Takahashi + Canon DSLR. Despite their disparate focal lengths this works reasonably well as my current Canon has 4.3 micron pixels (plate scale 2 arcsecs/pixel) and the Apogee 18 micron ones when binned 2x2 (plate scale 1.3 arcsecs/pixel). I find binning essential to maximise signal and improve the signal-to-noise ratio.

The images are all taken from my back garden and appear in order of me processing them - we have plenty of cloudy nights for that. I use a combination of IRIS and Maxim for processing with final tweaks in Photoshop. To get rid of the light pollution takes much trial and error. IRIS scores here with several options but processing often comprises many nights work - certainly always longer than the actual taking. The exception are images taken with an h-alpha filter which is a superb light pollution filter. It also permits imaging with strong Moonlight present - isn't it funny how it always seems to be clear at full Moon!



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20th NOVEMBER 2016

Planetary Nebula Abell 78


Located in Cygnus. Abell 78 is one the rare class of "born again" planetary nebulae. This object was studied by ESA using their XMM-Newton X-ray space based obseravtory. The following is from the subsequent research paper by J.A. Toalá et al. 2015:-

"Although nuclear burning of hydrogen and helium had ceased in the core of the dying star, causing it to collapse under its own weight and its envelope to expand into a bubble, some of the star’s outer layers became so dense that fusion of helium resumed there. The renewed nuclear activity triggered another, much faster wind, blowing more material away. The interplay between old and new outflows has shaped the cloud’s complex structure, including the radial filaments that can be seen streaming from the collapsing star at the centre."

Quite a faint object but I perhaps went a bit overboard with the equivalent of 13.5 hours worth of exposures!

Image Details

  • Dates: 3rd, 5th & 6th October 2016
  • Telescope: RCOS 12.5 inch at f/9 and Takahashi FSQ106N
  • Camera: Apogee Alta U9 and Canon 60D
  • Exposures: H-alpha 9 x 20 mins, OIII 11 x 20 mins + RGB 42 x 10 mins (Tak) = 13.5 hours

Abell 78


6th NOVEMBER 2016

Emission Nebula Sh2-140


A good name for the nebula would be the Seagull Nebula but unfortunately that name has already been used for Sh2-296. The blue stars are obviously a young open star cluster in the foreground but they don't appear to have a catalogue number of their own.

Galaxy Map states the following "Sh 2-140 is part of the Cepheus Bubble, the expanding shell of gas and dust surrounding the Cep OB2 association. The bright rim is created by the B0.5 V double star HD 211880 ionising a Bok globule located within the southwest side of the LDN 1204 molecular cloud".

Not one of Sharpless' best objects but with a 98% full Moon then it had to be a high DEC h-alpha target.

Image Details

  • Dates: 17th September 2016
  • Telescope: RCOS 12.5 inch at f/9 and Takahashi FSQ106N
  • Camera: Apogee Alta U9 and Canon 60D
  • Exposures: H-alpha 8 x 20 min + Colour RGB 16 x 10 mins (Tak)



9th OCTOBER 2016

Emission Nebula Abell 71, Sh2-116


The central object in my image is known as Abell 71 and also Sh2-116 - for what kind of nebula it is read on. The much larger surrounding object is Sh2-115, an emission nebula.

Abell71/Sh2-116 has a complicated history. This time it was Abell who mis-classified it although perhaps Perek & Kohoutek (1967) should take some of the blame as they too classed it as a planetary nebula. Abell 71 is actually an emission nebula. It does appear to have an unusual spiral pattern so was perhaps an easy mistake to make. The issue was settled as long ago as 1991 by Pismis at al. in "A comparative study of the Morphology and Velocity Field of the Emission Nebula S153, S207, S212, and A71". This was based on its similarities to Sh2-153 (S153) and Sh2-207 (S207) plus the fact there was virtually no OIII emission present - a standard feature of planetary nebulae.

Image Details

  • Dates: 16th September 2016
  • Telescope: RCOS 12.5 inch at f/9 and Takahashi FSQ106N
  • Camera: Apogee Alta U9 and Canon 60D
  • Exposures: H-alpha 9 x 20 min + Colour RGB 17 x 10 mins (Tak)

Abell 71 & Sh2-115,116


25th SEPTEMBER 2016

Planetary Nebula NGC 6842, Sh2-95


What was Stewart Sharpless thinking about when he included this object in his catalogue of (red) emission nebula? It is not an emission nebula and it is definitely not red.

Virtually the only background information I could find was from the Kopernik Observatory & Science Center: "NGC 6842 was discovered in 1919 by Curtis. In has a faint 14th magnitude irregular disk with traces of ring structure. The central star is magnitude 16.2, and the nebula is about 50 arc seconds in diameter". Not sure about that ring structure though - more like a helix?

Its distance is around 4000 light year according to Phillips (2004): Planetary nebula distances re-examined: an improved statistical scale. Located in Vulpecula

Image Details

  • Dates: 11th September 2016
  • Telescope: RCOS 12.5 inch at f/9 and Takahashi FSQ106N
  • Camera: Apogee Alta U9 and Canon 60D
  • Exposures: OIII 8 x 20 min + Colour RGB 21 x 10 mins (Tak)

Sh2-95 - NGC 6842


15th SEPTEMBER 2016

A Ring Nebula in Lyra - Minkowski 1-64 (PK 64+15.1)


This is the "other" ring nebula in Lyra - a little less famous than M57. It is a lot lot smaller too at 1/10th the size - it is only 18 arcseconds across whereas M57 is 180 arcseconds wide. It is located to the north of M57 and just about dead centre of Lyra. It responds well to both H-alpha and OIII.

Rudolph Minkowski was a specialist in spectroscopy and worked on supernovae but in the 1940s he created a catalogue of around 200 planetary nebulae. These were not discovered with the 48 inch Palomar Schmidt telscope as might be expected but ones he had identified with the 60-inch & 100-inch telescopes at Mount Wilson. This gives a clue that they are generally very small.

Image Details

  • Dates: 2nd and 5th September 2016
  • Telescope: RCOS 12.5 inch at f/9 and Takahashi FSQ106N
  • Camera: Apogee Alta U9 and Canon 60D
  • Exposures: Ha 6 x 20 min + OIII 6 x 20 mins + Colour RGB 21 x 10 mins (Tak)
Mink 1-64 PN

Minkowski 1-64


31st AUGUST 2016

Mars, Saturn & Antares - 14th August 2016


Although low down this was too good a conjunction to miss. Foreground is Rivington, Lancashire - the ruins in the Japanese Gardens.

Image Details

  • Date: 14th August 2016
  • Telescope: None - fixed tripod
  • Camera: Canon 40D + 50mm lens at f/4.
  • Exposure: 1 x 1 second

Mars, Saturn and Antares Conjunction 2016


4th AUGUST 2016

Saturn - altitude only 15.5 degrees


The usual summer weather meant a long wait before a clear night came along for me to image Saturn. Fainter than Mars so 10 frames per second was as fast as I could go but the seeing was much btter than when I attempted Mars. Again the homemade ADC unit was used with a separation of 45mm.

Image Details

  • Time/Date: Between 21:00 to 21:15 UT (22:00 - 22:15 BST) 29th July 2016
  • Telescope: Celestron Celestar 8-inch SCT @ f/20 with ADC unit set to 45 mm prism spacing.
  • Camera: Microsoft Lifecam Webcam
  • Exposure: 1500 frames from 5000 shot at 10 fps.
Saturn 2016
Saturn at 15.5 degress altitude


24th JULY 2016

Bode's Galaxy, M81


Is it possible to image Arp's loop from light polluted Lancashire? I wanted to find out and after 6 hours worth of exposures over 3 nights then answer was just about yes. Because of it size I had to resort to a mosaic to fit it all in and even then I could have done with a bit more sky coverage. Arp's Loop is at the top (north) of my image and left of centre.

M81 is not alone and is the largest galaxy in its group which also includes M82 (NGC3034), NGC3077 and NGC2976. The group has certainly undergone interactions in the past and Holmberg IX - left (east) of M81 - is left over debris from one such interaction. In 1965 Halton Arp detected this loop on plates taken with the 48-inch Schmidt on Mount Palomar. Initially it was thought Arp’s loop was a tail resulting from the tidal interaction between M81 and M82 . However, this region of the sky is known to be filled with galactic cirrus and Arp’s loop does exhibit properties similar to those observed in galactic cirrus clouds. So perhaps on balance it is more likely part of the Milky Way and not associated with M81 after all.

Image Details

  • Dates: 13th, 14th & 17th March 2016
  • Telescope: RCOS 12.5 inch at f/9 and Takahashi FSQ106N
  • Camera: Apogee Alta U9 and Canon 60D
  • Exposure: Luminance 18 x 20 mins + Colour RGB 24 x 10 mins (Tak)


26th JUNE 2016

Keenan's System (Arp 104)


This intriguing system was discovered by Keenan in 1935 and then forgotten about until rediscovered in the 1950s and entered in Arp's Atlas of Peculiar Galaxies as number 104.

Note many web sites featuring this object, including Wiki and APOD, have the distance hugely wrong and some have also mixed up the galaxies catalogue numbers showing they have blindly copied each other's errors! To put the record straight:-

Distance is c. 135 million light years (42Mpc)

Southern galaxy (left in my image) is NGC 5216 - an elliptical

Northern galaxy (right in my image) is NGC 5218 - disturbed spiral possibly barred but see later.

Probably the best source of information on this pair is by Gallagher & Parker: Optical Structure and Evolution of the Arp 104 Interacting Galaxy System (Astro-ph 2010). Their conclusion is that the pair are now separating after a close passage 300 million years ago and the bridge is stars dragged out from the outskirts of NGC 5218. They also favoured NGC 5218 being itself the result of an earlier minor merger. The system's eventual fate, they concluded, was likely to be a single galaxy although its type would depend on how much gas was remaining at that time.

Image Details

  • Dates: 31st March & 25th April 2016
  • Telescope: RCOS 12.5 inch at f/9 and Takahashi FSQ106N
  • Camera: Apogee Alta U9 and Canon 60D
  • Exposure: Luminance 10 x 20 mins + Colour RGB 20 x 10 mins (Tak)

Gallagher & Parker Fig. 1. Left is an extreme stretch to show faint features.


Keenan's system

Keenan's System

12th JUNE 2016

Galaxy NGC 3079 & the Gravitational Lens Quasar (QSO 0957+561 A/B)


In 1972, the Lovell Telescope at Jodrell Bank in a systematic survey discovered 800 radio sources. Follow up visual observation in 1979 by Walsh et al. identified this one as being double. Both had similar spectra and redshifts and they proposed that this was infact the same quasar being observed twice via a gravitational lens.

One of the predictions of Einstein's Theory of General Relativity is that a massive object will distort the space around it forming what is called a Gravitational Lens. This causes light and radio waves from an object behind it to follow curved paths in its vicinity, producing multiple or distorted images of the same object. The massive object doing the bending in this case is a galaxy cluster.

Subsequent research has confirmed this as correct. The quasar images are 6 arcseconds apart and are magnitude 16.7 but they do vary. These variations observed over 30 years have shown that image A of the quasar reaches earth about 417 days earlier than the corresponding image B. Their separation of 6 arcseconds and light path diffrence of 417 light days has enabled an independent geometric check on their distance to be calculated. The redshift derived distance and this geometric distance agree. This was one of the results that confirmed the immense distance of quasars and that their redshifts are real.

North is to the right in my image.

Image Details

  • Dates: 7th March 2016
  • Telescope: RCOS 12.5 inch at f/9 and Takahashi FSQ106N
  • Camera: Apogee Alta U9 and Canon 60D
  • Exposure: Luminance 11 x 20 mins + Colour RGB 22 x 10 mins (Tak)

The Gravitational Lens quasar imaged by the Jodrell Bank Merlin telescope array.

Note the jets from image A are not seen in image B. This is because the precise alignment necesaary for lensing is only correct for the quasar itself.


Gravitational Lens Quasar


5th JUNE 2016

Mars - altitude only 13 degrees


The ultimate test of my ADC unit on Mars at an altitude of only 13 degrees. Sure the dispersion was brilliantly cancelled out but the turbulence at this low elevation was incredible. I was surpised the resulting image was reasonably round - some features being discernible was an unexpected bonus. The simulation is from the Astronomy Now Mars Mapper. It shows a north polar cap but my guess is had melted by the time I took this image.

Not a winner but it was good fun trying get anything at this height when shooting straight over the top of Manchester.

Image Details

  • Date: 21:45 UT (22:45BST) 2nd June 2016
  • Telescope: Celestron Celestar 8-inch SCT @ f/20 with ADC unit set to 48 mm prism spacing.
  • Camera: Microsoft Lifecam Webcam
  • Exposure: 500 frames of a 5000 frame video shot at 30 fps.
Mars at 13 degress altitude

22nd MAY 2016

Edge-on Galaxy, IC 2233


IC 2233 is one of the flattest galaxies known. It is a prime example of a super-thin galaxy, where the galaxy’s diameter is at least ten times larger than the thickness. IC 2233 is actually a bulgeless Sd galaxy located at a distance of around 33 million light years.

However, IC 2233 is much more complex than it looks. Matthews & Uson (2008) discovered a regular corrugation pattern in the H i disk. They meaured the vertical structure of this galaxy at several additional wavelengths, ranging from the far-ultraviolet to the far-infrared. they found the corrugations were prominent in Population I stars, including the young to intermediate-age stars, the H ii regions, and the dust. However, the vertical displacements become less pronounced in the older stellar populations traced by the mid-infrared light. They suggested that the process leading to the vertical displacements may be linked with the regulation of star formation in the galaxy.

This galaxy was discovered by pioneer British astro-photographer Isaac Roberts in 1894. He was president of Liverpool Astronomical Society and had an observatory in Birkenhead. He is most famous for his photograph of M31 - the first to fully reveal its true form and extent.

Image Details

  • Dates: 28th February 2016
  • Telescope: RCOS 12.5 inch at f/9 and Takahashi FSQ106N
  • Camera: Apogee Alta U9 and Canon 60D
  • Exposure: Luminance 12 x 20 mins + Colour RGB 21 x 10 mins (Tak)



IC 2233

13th MAY 2016

Transit of Mercury 2016


Would you believe it - it turned out Lancashire was one of the best places on Earth to see the transit of Mercury! Our society observed the start and middle phase at Bolton School but there was time to get home and set up for a final view.

This was the last view of it from my back garden before it disappeared behind trees.

Image Details

  • Dates: 9th May 2016
  • Telescope: Celestron C8 + Thousand Oaks off-axis filter
  • Camera: Canon 60D
  • Exposure: 10 x 1/250th second


Mercury Transit

Mercury Transit 2016

5th MAY 2016

The Bear's Paw Galaxy, Arp 6


The first entry in Arp's Catalogue of Peculiar Galaxies that looks peculiar! It is generally classed as a BCD - Blue Compact Dwarf - and as such comprises a elliptical/spherical halo with several very bright star forming knots. However, the NASA NED database classes it as a barred spiral and there does seem to be perhaps a barred spiral lurking behind the start burst knots.

Also known as Markarian 86 (he liked blue objects) but more commonly known as NGC 2537. Located in Lynx and it is at a distance of around 25 million light years.

The small (spiral?) galaxy to the left is NGC 2537A but is an unrelated background object.

Image Details

  • Dates: 28th February 2016
  • Telescope: RCOS 12.5 inch at f/9 and Takahashi FSQ106N
  • Camera: Apogee Alta U9 and Canon 60D
  • Exposure: Luminance 12 x 20 mins + Colour RGB 21 x 10 mins (Tak)


Bear Paw

The Bear's Paw Galaxy

20th APRIL 2016

The Seahorse Nebula (Sharpless Sh2-249)


The "Seahorse" is part of the very large nebula Sh2-249 (IC444). It is located to the north east of the supernova remnant IC443 (Sh2-248) and the association or otherwise of these two nebula is the subject of some debate. Probably the definitive paper was by Robert Fesen way back in 1984. He produced evidence that the supernova was indeed interacting with the edge of Sh2-249 thus placing them at the same distance. Yet in the same year, Donati-Falchi & Tafani concluded the exact opposite - Sh2-248 and Sh2-249 were not adjacent and interacting.

What is generally agreed is that Sh2-249 is energised by stars in the Gemini OB1 association

Image Details

  • Dates: 23rd February 2016
  • Telescope: RCOS 12.5 inch at f/9 and Takahashi FSQ106N
  • Camera: Apogee Alta U9 and Canon 60D
  • Exposure: Luminance (Ha) 9 x 20 mins + Colour RGB 18 x 10 mins (Tak)



The Seahorse Nebula


13th APRIL 2016

Jupiter - altitude 40 degrees


First test of my ADC unit on Jupiter at an altitude of 40 degrees. This altitude is probably marginal as to whether the gain in resolution (no dispersion) is greater than the effect of 2 extra glass elements (prisms) in the opical train.

The Microsoft Webcam was acting up though. Unbenown to me the Microsoft Lifecam software had re-installed itself. Sharpcap needs it to be removed to work properly but I didn't realise this till the next day. I need a check list as I only image the planets once or twice per year.

Image Details

  • Dates: 30th March 2016
  • Telescope: Celestron Celestar 8-inch SCT @ f/20 with ADC unit set to 13.5mm prism spacing.
  • Camera: Microsoft Lifecam Webcam
  • Exposure: 625 frames of a 1250 frame video shot at 10 fps.
Jupiter 30th March 2016

15th MARCH 2016

Sharpless Sh2-241 & Van den Bergh 65


I could not find a great deal of information about this rather forgotten Sharpless object located down at the bottom of Auriga. Just a single paper by Vallee in 1987 gives some basic information and describes it as "a blister-type HII region on the surface envelope of a molecular cloud". The latter is listed as G180.9+4.1 and is located behind Sh2-241.

My image also contains the blueish reflection nebula Van den Bergh 65, which is a completely unrelated object. Wiki has some basic information and gives a distance of around 3600 light years. It is just part of a larger area of obscuring clouds.

Image Details

  • Dates: 14th February 2016
  • Telescope: RCOS 12.5 inch at f/9 and Takahashi FSQ106N
  • Camera: Apogee Alta U9 and Canon 60D
  • Exposure: Luminance 10 x 20 mins + Colour RGB 20 x 10 mins (Tak)



Sh2-241 & VdB65

1st MARCH 2016

The Spaghetti Nebula, Simeis147


This very faint supernova remnant in Taurus is big - about 6 full Moons wide i.e. 3 degrees. It's distance is estimated at 3,000 light years and that means its real size would be around 150 light years across. It is the result of a stellar explosion that occurred 40,000 years ago which produced the nebula and left being pulsar PSR J0538+2817. The latter emits a strong radio signal discovered as part of the NRAO VLA Sky Survey.

Without using mosaics, then a 200mm lens is perfect on my Canon 60D for this object. There are never enough clear nights for mosaics in Lancashire. This time I used an Astronomik 6nm H-alpha clip filter and the result was much better than the 12nm one I had used 2 years ago.

It was also catalogued by Sharpless as Sh2-240. The tiny nebula at the 8 o' clock position is Sh2-242.

Image Details

  • Dates: 15th January 2016 with colour from February/March 2014
  • Telescope: Canon 200mm Lens at f/2.8
  • Camera: Canon 60D
  • Exposure: Luminance H-alpha 26 x 10 mins + Colour UHC 17 x 10 mins




Simeis 147

14th FEBRUARY 2016

The Dwingeloo Galaxies


Part of the Maffei/IC342 group of galaxies but even fainter. Infra-red is all but essential to record these three.

Dwingeloo 1 and 2 were discovered in 1994 as part of the Dwingeloo Obscured Galaxy Survey (DOGS) - Dwingeloo is a Dutch 25 metre radio telescope. These two are therefore radio galaxies. MB3 on the other hand is radio quiet so they did not detect it. It was found later by McCall and Buta when they were searching for other members of the group.

Dwingeloo 1 is a classic barred spiral galaxy. Dwingeloo 2, is an irregular galaxy and largely obscured by an overlying bright star. MB 3 is surprisingly bright and thought to be a dwarf spheroidal galaxy.

Image Details

  • Dates: 14th January 2016
  • Telescope: RCOS 12.5 inch at f/9 and Takahashi FSQ106N
  • Camera: Apogee Alta U9 and Canon 60D
  • Exposure: Luminance 10 x 20 mins + IR 60 mins. Colour RGB 20 x 10 mins (Tak)




The Dwingeloo Galaxies

1st FEBRUARY 2016

Barred Spiral Galaxy Maffei 2


About 3/4 degree further east than Maffei 1, is the barred spiral galaxy Maffei 2 - also discovered by Paulo Maffei using infra-red film. It is much fainter but is still within range of amateur telescopes. The 4-inch Tak + DSLR used for the colour information in my image had no trouble in recording it despite the DSLR being blind to the infra-red.

Without the Milky Way blocking the view, this would be the best barred spiral in the northern hemisphere. Fingerhut et al. (2007) found that Maffei 2 was significantly more obscured than Maffei 1 despite being so close together on the sky.

The north of the galaxy is much disturbed and looks a bit odd. Hurt et al. (1996) found that this was most likely caused by a recently merged companion galaxy and the northern feature is probably a streamer from that merger.

The distances to the Maffei galaxies has always been difficult. The latest estimates are by Wu et al. (2014) placing Maffei 1 at 11 million light years and Maffei 2 at 11.5 million light years.

Image Details

  • Dates: 8th & 10th January 2016
  • Telescope: RCOS 12.5 inch at f/9 and Takahashi FSQ106N
  • Camera: Apogee Alta U9 and Canon 60D
  • Exposure: 9 hours total: Luminance 240 mins + IR 60 mins. Colour RGB 24 x 10 mins (Tak)




Maffei 2

17th JANUARY 2016

Elliptical Galaxy Maffei 1


Lying close to the popular Heart and Soul Nebulae, this elliptical galaxy is often imaged but seldom recognised. Being almost directly behind the plane of the Milky Way it is heavily obscured and this has made determining its distance somewhat problematical. A good compromise figure is around 10 million light years - just beyond our local group. If it was not so obscured it would be one of the showpieces of the northern sky. It was discovered by Paulo Maffei in 1967 using Infra-red sensitive film.

Although it was discovered by Paulo Maffei using infra-red film it does show up when imaged in the visible as a deep red glow. Infra-red however, does reveal its large size. To produce this image I combined visible and infra-red together so this is a somewhat false-colour image as our eyes don't see infra-red.

Image Details

  • Dates: 6th, 8th, 10th December 2015
  • Telescope: RCOS 12.5 inch at f/9 and Takahashi FSQ106N
  • Camera: Apogee Alta U9 and Canon 60D
  • Exposure: 7 hours total: Luminance 120 mins + IR 60 mins. Colour RGB 22 x 10 mins (Tak)




Maffei 1

3rd JANUARY 2016

Globular Cluster, C39


Yes - a globular cluster in another galaxy. If you think this is one just for big telescopes then you are in for a shock. It is surprisingly bright at magnitude 16 given its huge distance of 2.4 million light years and is well within reach of modest refractors.

It looks like a fuzzy star - don't expect to see individual stars at this range. With a larger telescope (12.5-inch) it becomes obvious it isn't a star but the cluster is not resolved. It would need the Hubble Space Telescope to see individual stars. So if you are up for the challenge of imaging a globular cluster in another galaxy then C39 is probably the best target. If you have imaged M33 before, you may have already recorded it - just check out your image - it could well be there. A globular cluster in another galaxy - in this case M33. Despite being 2.4 million light years distant it is surprisingly bright

Image Details

  • Dates: 21st & 22nd November 2015
  • Telescope: RCOS 12.5 inch at f/9 and Takahashi FSQ106N
  • Camera: Apogee Alta U9 and Canon 60D
  • Exposure: 7 hours total: CLS luminance - 11 x 20 mins + RGB 22 x 10 mins (Tak)




Globular Cluster C39

20th DECEMBER 2015

Compact Galaxy Group, Hickson 99


Not one of the most spectacular of the Hickson groups with its brightest galaxy down at magnitude 14. It comprises 4 spirals and 1 elliptical.

According to Hickson, they are a genuine "accordant" group ie their redshift tally (around z=0.029). He reckoned b and c were interacting but c (the barred spiral) looks beautifully symmetrical. Galaxy a is clearly a spiral but the bright star in front of it spoils the view.

There are several galaxies around the group so it could be the case of a compact group at the centre of a loose cluster. Most don't have recorded reshifts but the elliptical at the bottom right of the full image does and it matches that of the group.

Image Details

  • Dates: 17th, 22nd October & 1st November 2015
  • Telescope: RCOS 12.5 inch at f/9 and Takahashi FSQ106N
  • Camera: Apogee Alta U9 and Canon 60D
  • Exposure: 7 hours total: CLS luminance - 10 x 20 mins + RGB 22 x 10 mins (Tak)




Hickson 99

6th DECEMBER 2015

Globular Cluster, Pal 13


Located just below the Square of Pegasus and near to NGC7479, Pal 13 one of the smallest and faintest globular clusters known. It was discovered by A.G. Wilson in 1953. Its distance is 85,000 light years and its brightest stars mag 17.

Palomar 13 was the only known globular cluster with possible evidence for dark matter, based on a Keck/HIRES 21 star velocity dispersion. However, research by Bradfod et al. (2011) found its dynamics could be explained on the basis of its stellar mass alone and the presence of dark matter was not required. Trouille et al. (2003) found its age to be around 10.5 billion years - a bit younger than most other Milky Way globulars.

Image Details

  • Dates: 14th October 2015
  • Telescope: RCOS 12.5 inch at f/9 and Takahashi FSQ106N
  • Camera: Apogee Alta U9 and Canon 60D
  • Exposure: 6 hours total: CLS luminance - 9 x 20 mins + RGB 18 x 10 mins (Tak)




Pal 13

22nd NOVEMBER 2015

Compact Galaxy Group, Hickson 94 (Arp 170)


Located within the Square of Pegasus, this Hickson group of 7 galaxies is not all that it seems. Arp also included this, or at least the central 3, as no. 170 in his Atlas of Peculiar Galaxies. The extended envelope around (a), (b) & (c) is very odd and very asymmetric.

I was not very convinced that this is really a "Compact Group" - there are several galaxies around the Hickson 7 and when I checked their redshift many had the same redshift as the central 3. So in all probability they are all located nearby. In addition, (d) and (f) have larger redshifts. The redshifts of (a), (b) & (c) indicate a distance of around 550 million years whereas that of (d) and (f) indicate a distance of 590 mly. Quite a disparity for a true group.

I trawled the research papers to try and resolve what was the real situation. It turns out, Ebeling et al. (1995) had already come to the same conclusion. Hickson 94 is not a galaxy group but a the core of a loose cluster of galaxies. They termed it the most extreme misclassification in the Hickson catalogue.

Hickson member Name Redshift
94a HGC 7578b 0.0402
94b NGC 7578a 0.0403
94c   0.0398
94d   0.0434
94e   0.0409
94f   0.0435
94g   0.0440

Redshifts from Aladin

Image Details

  • Dates: 12th October 2015
  • Telescope: RCOS 12.5 inch at f/9 and Takahashi FSQ106N
  • Camera: Apogee Alta U9 and Canon 60D
  • Exposure: 6 hours total: CLS luminance - 10 x 20 mins + RGB 20 x 10 mins (Tak)



Hick 94

Hickson 94

8th NOVEMBER 2015

Compact Galaxy Group, Hickson 93 (Arp 99)


Located within the Square of Pegasus, this compact group of 5 galaxies is centred on the distorted elliptical galaxy NGC 7550. Paul Hickson described this group as an accordant quartet (a, b, c & e) with (d) the odd one out and not part of the group. In reality (e) is the background galaxy with a much higher redshift. Perhaps when he compiled his catalogue there was redshift error? Interestingly the anonymous galaxy (see right) has the same redshift as (e) so these 2 probably form a background pair in their own right.

Hickson member Name Redshift
93a HGC 7550 0.0169
93b NGC 7549 0.0158
93c NGC 7547 0.0159
93d NGC 7553 0.01725
93e NGC 7558 0.0296
anon (2MASX) 0.0300

The "anon" galaxy does have a 2MASX number.
Arp 99 seems to comprise just the 3 brighter galaxies - a, b and c.

Image Details

  • Dates: 18th & 30th September 2015
  • Telescope: RCOS 12.5 inch at f/9 and Takahashi FSQ106N
  • Camera: Apogee Alta U9 and Canon 60D
  • Exposure: 6 hours total: CLS luminance - 8 x 20 mins + RGB 20 x 10 mins (Tak)


Key to group members

Hickson 93

Hickson 93

25th OCTOBER 2015

Planetary Nebula, Abell 72


Located in Delphinus, this rather poorly known planetary nebula is catalogued as magnitude 13.8 and with a size of 2.2 arcminutes on its long axis. The central star is magnitude 16.1 visual but much brighter in the ultra-violet.

I could find very little information for this nebula and the only research paper mentioning it I could find is "Spectroscopy of six highly evolved Abell planetary nebulae" - J. P. Phillips et al., 2005. Even so there wasn't a lot of startling revelations - just "the structure of this shell appears complex, and reveals evidence for at least four primary emission peaks". Oh well, that's the price for imaging obscure objects.

Just below (south) of the nebula is the background galaxy PGC 65491, which appears to be a somewhat distorted spiral.

Image Details

  • Dates: 7th, 9th & 15th September 2015
  • Telescope: RCOS 12.5 inch at f/9 and Takahashi FSQ106N
  • Camera: Apogee Alta U9 and Canon 60D
  • Exposure: 11 hours total: OIII - 16 x 20 mins + RGB 34 x 10 mins (Tak)


Abell 72

7th OCTOBER 2015

Emission Nebula, Sharpless Sh2-90


Located in Vulpecula, this is not one of the most spectacular Sharplees objects.

Sh2-90 has a diameter of around 10 light years and is at a distance of 10,000 light years. According to "Galaxy Map", Sh 2-90 is a blister on a 60 thousand solar mass molecular cloud and appears to be affected by gas streaming from the Vul OB1 association. It contains a cometary elephant trunk structure on its eastern edge which appears to have originated from a past disturbance from the southwest.

Lafon et al. (1883) thorougly investigated this nebula and the following is based on their conclusions. The exciting star they thought must be too well hidden to detect discounting other previous suggestions. However, they thought this star had formed at the near edge of the molecular cloud. The HII region was composed of a cavity, dug into the molecular cloud, and of an extended region lying outside the molecular cloud. The densest regions cover the cavity, thus producing a shell structure of low excitation with the south diffuse extension formed by the ionized gas, streaming away supersonically from the open cavity, more or less in the direction of the observer. A pretty complex object!

Image Details

  • Dates: 5th September 2015
  • Telescope: RCOS 12.5 inch at f/9 and Takahashi FSQ106N
  • Camera: Apogee Alta U9 and Canon 60D
  • Exposure: 4 hours total: Ha - 6 x 20 mins + RGB 12 x 10 mins (Tak)



23rd SEPTEMBER 2015

Milky Way over Kelling Heath


This year's star party at Kelling Heath was a great success with several clear nights. There were though clouds passing over rather too frequently to make all-sky imaging easy. The light pollution has got worse over the year's but it is not a show stopper.

Tried a Samyang 8mm Fish Eye lens this year on my Canon. This lens has a strange optical design and cannot be used with clip-in filters. The back focus distance of this lens doesn't change with focusing so cannot reach focus with the filter in place. I would have used a CLS light pollution filter if I could to stop that glow from Holt (bottom right). Still the quality of the lens was impressive with very little fall off in sharpness in the corners.

Image Details

  • Dates: 12th September 2015
  • Telescope: Bolton Tracker
  • Camera: Canon 40D with Samyang 8mm Fish Eye lens
  • Exposure: 4 x 5 mins at f/5.6


Milky Way, Kelling Heath

1st SEPTEMBER 2015

Planetary Nebula Abell 56


First image of this autumn's session. Listed as magnitude 14.1 but effectively it is much fainter than that! The large number of stars makes it difficult to drag it up out of the background.

I couldn't find any information on this planetary - no research papers seem to have covered it. The following is from Reiner Vogel's catalogue of Abell Planetary Nebulae:

Names: Abell 56, PK 37-3.2
RA: 19:13.1
DEC: +02 53
Mag: 14.1
Diameter: 3 arcmins
Constellation: Aquila

Image Details

  • Dates: 12th August 2015
  • Telescope: RCOS 12.5 inch at f/9 and Takahashi FSQ106N
  • Camera: Apogee Alta U9 and Canon 60D
  • Exposure: 4.5 hours total: Ha - 7 x 20 mins + RGB 14 x 10 mins (Tak)

Abell 56

Abell 56

20th JULY 2015

NGC 5005, (Caldwell 29)


A spiral galaxy with a small bar and classed as a LINER, somewhat similar to Seyfert galaxies (Viegas-Aldrovandi & Gruenwald, 1990). LINER stands for Low-Ionisation Nuclear Emission-line Region and was devised by Hechman (1980) to describe a new class of emitting region in the nuclei of galaxies. The existence of a LINER in the galactic nucleus is related to the presence of a compact nuclear radio source. The source of the emission of LINERS could be from the ionising radiation caused by massive stars (called “warmers”) or from the accretion disc around a black hole. The latter seems to be more in favour.

Paul Eskridge et al. (2002) described this galaxy in detail "Appearance—SBa: System is fairly inclined. Bright, elliptical bulge with a flattened nuclear source. Bulge is threaded by a bar with a P.A. skewed 30 from that of the bulge. The outer bulge isophotes are boxy, and the bar crosses the diagonal of the bulge. There are two ansae near the ends of the bar. Two very narrow spiral arms. The inner arms have some evidence for star-forming knots and are quite open. However, the outer arms tighten and appear to wrap several times around the system. The outer disk shows an occasional knot, but there is no coherent star-forming pattern associated with the outer arms".

Kazushi Sakamoto et al. (2000) studied the gas dynamics of NGC 5005 in detail - see their figure 8 to the right.

Another Caldwell object for which I needed a better image but nights were getting too light so only a short exposure. The faint dwarf galaxy towards the top edge (north) is PGC166157. This was my last image before the summer shut down.

Image Details

  • Dates: 26th April 2015
  • Telescope: RCOS 12.5 inch at f/9 and Takahashi FSQ106N
  • Camera: Apogee Alta U9 and Canon 60D
  • Exposure: 4 hours total: Luminance - 13 x 10 mins - RGB 13 x 10 mins (Tak)
Diagram copyright Sakamoto et al., 2000.
Note UHR = ultra-harmonic resonance.
NGC 5005

NGC 5005


8th JULY 2015

Saturn - altitude 18 degrees


A much more severe test of whether the ADC I had built last winter would work. Well it certainly has cancelled out the atmopheric dispersion - no adjustment of the colour planes was needed for this image. However, it cannot (unfortunately) cancel out the mushy Lancashire atmosphere! Still it's an image at an altitude where really nothing much can be expected. Roll on Mars at 15 degrees altitude next year.

Image Details

  • Dates: 4th July 2015
  • Telescope: Celestron Celestar 8-inch SCT @ f/20 with ADC unit set to 36mm prism spacing.
  • Camera: Microsoft Lifecam Webcam
  • Exposure: 1000 frames of a 1500 frame video shot at 10 fps.
Saturn 2015

5th JULY 2015

The Draco Trio, NGC 5981, 5982 & 5985


Appearances can be deceptive - probably not a true trio at all. The redshifts for these 3 galaxies pose questions as to their proximity to each other:-

NGC 5981: redshift velocity = 1894 km/sec
NGC 5982: redshift velocity = 3046 km/sec
NGC 5985: redshift velocity = 2694 km/sec

Probably NGC 5982 and NGC 5985 form a wide non-interacting physical pair but NGC 5981 is more likely not associated and nearer to us. NGC 5982 & 5985 are probably around 115 million lightyears with NGC 5981 probably well under the hundred mark.

Edge-on spiral NGC 5981 is slightly disturbed and asymmetric. The inner disc is tilted against the outer disc and the bulge component is furthermore slightly tilted against the inner disc.

NGC5982 is an elliptical shell galaxy with regular major axis shells (Sikkema et al. 2007). This galaxy harbours a Kinematically Decoupled Core (KDC: Wagner et al. 1988), and probably a rotating central disk (Emsellem et al. 2004). Outside the core, the galaxy is slowly rotating (Emsellem et al. 2004).

Face-on spiral NGC 5985 has thin and well defined arms and perhaps a short bar.

I had taken a luminace image 6 years ago but had no colour information. As I was returning (at last) for colour I took the opportunity to take more luminance as well.

Image Details

  • Dates: 12th May 2009 and 22nd April 2015
  • Telescope: RCOS 12.5 inch at f/9 and Takahashi FSQ106N
  • Camera: Apogee Alta U9 and Canon 60D
  • Exposure: 6 hours total: Luminance - 23 x 10 mins - RGB 13 x 10 mins (Tak)
Draco Trio

Draco Trio

21st JUNE 2015

Caldwell 36 and X7 (Galaxy NGC 4559)


Galaxy Caldwell 36 or NGC 4559 is classed SAB(rs)cd. It is inclined at 67°to our line of sight and is around 30 million light years away.

When I wrote "Observing the Caldwell Objects" in 1999, I reported that several x-ray sources had been observed in NGC 4559 by Vogler et al., 1997. Aside from the (expected) one at its centre the next brightest, denoted X7, was located in an odd position, way out near the western edge of the galaxy. Since then the story has moved on with further observations by Soria et al., 2005 of the ultra-luminous x-ray (ULX) sources in NGC4559. Using Hubble images they were able to search the error box where X7 was located - the dotted box in the top inset in the image below. Vogler et al. had thought it must be from a 100 year old supernova, but Soria found that a black hole of around 50 solar masses accreting material from a 20 solar mass companion fitted the data better. The trigger for the formation of this huge black hole and companion they believed was an interaction with a dwarf galaxy (g in the inset). Soria et al. stated they would do further observations to check if the galaxy g was associated with Ngc 4559. So far I can find no published confirmation and, rather worryingly, this galaxy does look very small and therefore remote!

In 2012, the story got a bit more complicated. A possible supernova was discovered just south-east of X7. It turned out to be a Luminous Blue Variable (LBV) and it flared again in 2014. It seems to have been relatively quiet when I imaged it and also when Hubble imaged it. Perhaps it will flare again in 2016?

Image Details

  • Dates: 20th & 21st April 2015
  • Telescope: RCOS 12.5 inch at f/9 and Takahashi FSQ106N
  • Camera: Apogee Alta U9 and Canon 60D
  • Exposure: 7.5 hours total: IDAS-P2 -11 x 20 mins - RGB 21x 10 mins (Tak)

NGC 4559


14th JUNE 2015

Venus - shot using ADC


With the observatory shut for the summer, It was time to try out the ADC I had built last winter. Venus was a tempting target and its white colour would be a good test to see if atmospheric dispersion could be cancelled out - any false colour should be immediately apparent. It was at around 21 degrees elevation so the prisms were set to a spacing of 30mm. The image below has had no re-alignment of the colour planes and is a stack of 4000 images - no selection of best frames took place. So first signs are encouraging.

Image Details

  • Dates: 10th June 2015
  • Telescope: Celestron Celestar 8-inch SCT @ f/20 with ADC unit
  • Camera: Microsoft Lifecam Webcam
  • Exposure: All 4000 frames of a video at 30 fps.
Venus 2015

7th JUNE 2015

Galaxy NGC 4449, Caldwell 21


At last a galaxy perhaps worthy of its inclusion in the Caldwell Catalogue!

NGC 4449 is located 12.5 million light-years from Earth and is a member of a relatively nearby group of galaxies in the constellation Canes Venatici. It is classed as a dwarf galaxy and is very similar in size and morphology to one of the Milky Way's satellite galaxies, the Large Magellanic Cloud.

It is famous for its starburst activity and it seems that gravitational interaction with a merging galaxy has probably disturbed the gas in the main galaxy and caused the burst in star formation. Evidence for this interaction is the tidal or stellar stream (at about 7:00 o' clock in the images) that was first detected as a mysterious faint smudge in digitized photographic plates from the Digitized Sky Survey project. It is also visible in images from the Sloan Digital Sky Survey.

Authors of a recent study led by David Martínez-Delgado of the Max Planck Institute for Astronomy in Heidelberg, called it a stealth merger, where an infalling satellite galaxy is nearly undetectable by conventional means, yet has a substantial influence on its host galaxy.

I was surprised that just 7 x 20 minute exposures were enough to record the tidal stream despite being labelled as "nearly undetectable by conventional means". The Subaru image actually resolves both into their individual stars.

Image Details

  • Dates: 17th April 2015
  • Telescope: RCOS 12.5 inch at f/9 and Takahashi FSQ106N
  • Camera: Apogee Alta U9 and Canon 60D
  • Exposure: 5 hours total: IDAS-P2 - 7 x 20 mins - RGB 14 x 10 mins (Tak)

Image taken with the Subaru 8.2 metre telescope showing the tidal or stellar stream.


NGC 4449

31st MAY 2015

Galaxy NGC 3626, Caldwell 40


Again not a very spectacular object to warrant inclusion in the Caldwell Catalogue but it is a typical lenticular galaxy. Its fame (and its inclusion no doubt) is due to the fact that its gas orbits in one direction whilst its stars go in the opposite direction. It is around 65 million light years away and is on the outskirts of the Leo II Group of galaxies.

NGC 3626 is a large galaxy which has a huge amount of extended Hi gas which counterrotates to the stars. This is thought to as a result of a recent merger and this was recently confirmed by O. K. Sil’chenko et al., 2010. According to Friedli & Benz (1993) who studied this scenario, the initially counterrotating gas begins to inflow because of a bar and forms a stable highly inclined ring near the center due to resonance effects.

Though classified as SO/SA (non-barred), NGC 3626's large-scale structure reveals multi-tiered stellar disks and an inner oval disk. Therefore, O. K. Sil’chenko et al. suggest that the bar was present some time ago, but has now dissolved, or almost dissolved. The current star-forming ring in NGC 3626 may then be related to the resonance of this dissolving bar. O. K. Sil’chenko et al. explained this "The whole scenario of the galaxy transformations from spirals into lenticulars may include the following sequence of related events: first, a minor merger occurs, then the acquired gas and stars inflow to the center, the large-scale stellar disks develop bars and are heated, and the gas is compressed near the center and exhausted by the intense induced star formation. After a few billion years, we have typical lenticular galaxies, except for their unrelaxed gas behavior. Within such a scenario, the main mechanism of the lenticular galaxy formation is gravitational and not at all related to the intragroup hot medium impact". In the case of NGC 3626, they suggest its transformation from spiral to lenticular took place about 1 to 2 billion years ago.

Image Details

  • Dates: 14th April 2015
  • Telescope: RCOS 12.5 inch at f/9 and Takahashi FSQ106N
  • Camera: Apogee Alta U9 and Canon 60D
  • Exposure: 5 hours total: IDAS-P2 - 7 x 20 mins - RGB 14 x 10 mins (Tak)



NGC 3626

24th MAY 2015

NGC 4725 & LoTr5, Widefield


An amazing combination which shows clearly the huge apparent size of the planetary nebula, Lotr5. NGC 4725 is probably the biggest and best galaxy omitted from both the Messier and Caldwell catalogues. The distorted galaxy above the yellow/red bright star is NGC 4747.

I had taken the widefield shot last year and although Lotr5 was there, it was far too faint to have done it justice. So with this year's deep image of the planetary nebula I was able to put the two together and finish the job.

Image Details

  • Dates: 18th April 2014, 9th & 12th April 2015
  • Telescope: RCOS 12.5 inch at f/9 and Takahashi FSQ106N
  • Camera: Apogee Alta U9 and Canon 60D
  • Exposure: 16 hours total


NGC 4725 & LoTr5

17th MAY 2015

LoTr5, Planetary Nebula


A British discovery! Examining plates taken with the 1.2 metre UK Schmidt Telescope in 1980, Longmore and Tritton identified 11 new planetary nebula candidates of which this was number 5 - hence its catchy name of LoTr5.

Longmore & Tritton's description: "This is a very large very faint non-uniform disc, slightly brighter towards the centre. Two members of a distant group or cluster of galaxies can be seen through the nebula. It has been confirmed as a planetary nebula from a spectrum taken by David Allen using the IPCS on the AAT. The lines of [O m] II 4959, 5007 were seen, very weak after an 800-s exposure. It is the highest galactic latitude planetary known. The star SAO 82570 = HD 112313 = BD + 2602405, at a (1950) 12h 53m 07s.76, d (1950) 260 09' 44".3 is positioned at the centre of the nebula within reasonable measurement error. Its spectral type (from the SAO Catalogue) is G5, mpg = 9.5, mv = 8.7. Thus if the nebula is associated with the G5 star the latter probably has a hot dwarf companion".

They were right - the bright G star is much too cool to illuminate the nebula and does indeed have a very hot dwarf binary companion responsible for the PN. This companion star is one of the hottest known in the range 120,000 to 185,000 degrees. The cool G star is rapidly rotating and close to break-up. It is also barium rich making a very odd combination. Ref: Thevenin & Jasniewicx, 1997.

Set as a challenge by Owen Brazell, this planetary is large but faint and required 11 hours worth of exposures to record it. However, that OIII signal may make it visible to the big Dob boys. It is located close to NGC 4725.

Image Details

  • Dates: 9th & 12th April 2015
  • Telescope: RCOS 12.5 inch at f/9 and Takahashi FSQ106N
  • Camera: Apogee Alta U9 and Canon 60D
  • Exposure: 11 hours total: OIII - 17 x 20 mins - RGB 30 x 10 mins (Tak)

LoTr5 discovery

The discovery image taken with the UK 1.2 metre Schmidt and spotted by Longmore & Tritton (1980). The small blob at 11:00 o'clock is a background galaxy.




7th MAY 2015

Palomar 4, Globular Cluster


One of the Milky Way's most remote globular clusters - further away than our satellite galaxies the Magellanic Clouds. Until very recently is was the second most remote known. However, a very distant object at 145 kpc, PSOJ174.0675-10.8774, or Crater, was recently discovered simultaneously in two independent surveys (Laevens et al. 2014; Belokurov et al. 2014). As yet it has not been confirmed as a globular cluster so Pal4 is the second most remote at least for a bit longer.

The most recent research paper on Palomar 4 is by Akram Hasani Zonoozi, Hosein Haghi, Andreas H.W. Kuepper, Holger Baumgardt, Matthias J. Frank, Pavel Kroupa in 2014. A. Kuepper summarised their results: "By looking at the distribution of masses of stars within the cluster and their distance from the center of the cluster, we see that Palomar 4 must have been born as a very extended ball of stars and – and that’s the surprising discovery – with a very odd configuration for the masses of the stars. Massive stars must have been much more abundant in Palomar 4 than in young star clusters we observe today. And these massive stars must have preferentially been closer to the cluster center. It is not obvious why a globular cluster like Palomar 4 should have been born with an overabundance of high-mass stars, with a segregation of massive stars towards the cluster center, and with a very large extent. Models of star formation and cluster formation will have to explain this result".

Image Details

  • Dates: 22nd, 23rd & 26th March 2015
  • Telescope: RCOS 12.5 inch at f/9 and Takahashi FSQ106N
  • Camera: Apogee Alta U9 and Canon 60D
  • Exposure: Luminance - 13 x 20 mins IDAS-P2 - RGB 28 x 10 mins (Tak)

Properties (Frank et al., 2012)

Age: 11±1 billion years

Distance: 102± 2.4 kpc  333,000 light years (note this is lower than previous estimates of around 356,000 lys)

Half-light radius = 18.4 ± 2.0 pc  60 light years

Total mass = 29800 ± 800 solar masses

Brightest Star: 18th magnitude


Pal 4

Pal 4

28th APRIL 2015

Holmberg 124 (Galaxy Group NGC 2805)


Holmberg 124 is a group of four interacting galaxies: NGC 2805, NGC 2814, NGC 2820 and Markarian 108 at a distance of 90 million light years.

The most recent research paper for this group is by Mishra et al. 2013. They analised Hi 21cm data from the Giant Metrewave Radio Telescope (GMRT). They detected spectral line emission from all the four galaxies and noted several signatures of tidal interactions among the member galaxies. The results for the northern triplet (namely NGC 2820, NGC 2814 and Mrk 108) confirm the earlier results of Kantharia et al. (2005) - see diagram right. They also reported possible detection of small discrete clouds between NGC 2820 and NGC 2805 which might be stripped Hi in the intragroup medium (IGrM). The Hi distribution of NGC 2805 is asymmetric with peak Hi column densities seen along the southern spiral arm and along a northern arc. Vigorous star formation has been observed along the southern spiral arm of NGC 2805.

They also supported the scenario given by Kantharia et al. (2005) that both tidal interactions and ram pressure are currently playing a role in the evolution of the triplet galaxies. From the observed northern Hi arc and extensive star formation in the southern spiral arm of NGC 2805 and additionally the systemic velocities of the four galaxies, they suggest ram pressure effects are also playing a role in the evolution of NGC 2805. They believe interaction with the IGrM would have triggered star formation in the southern spiral arm. This model for NGC 2805 succeeds in explaining the compressed Hi in the north, widespread star formation and the diffuse Hi detected in the south/south-west of the optical galaxy.

Image Details

  • Dates: 21st March 2015
  • Telescope: RCOS 12.5 inch at f/9 and Takahashi FSQ106N
  • Camera: Apogee Alta U9 and Canon 60D
  • Exposure: Luminance - 10 x 20 mins IDAS-P2 - RGB 20 x 10 mins (Tak)

Holmmberg 124
Figure 10 from "GMRT observations of the group Holmberg 124: Evolution by tidal forces and ram pressure?" - N. G. Kantharia et al. (2005). Note they hedged their bets on which direction NGC 2805 was actually moving! It is however the best diagram I found for explaining what is going on in this system. It is not to scale though.
Note IGrM = intra-group medium


Holmberg 124

Holmberg 124

19th APRIL 2015

Galaxy NGC 2775, Caldwell 48


Not one of the best Caldwell Objects - it's hard to understand why this very ordinary galaxy was chosen. There was a supernova discovered in it in 1993 just about when the Caldwell Catalogue must have been compiled so I guess that's the likely reason.

Although classified as a spiral galaxy (Sa) and viewed almost face-on, it has no prominent spiral arms or dark lanes. This is the reason for it being visually rather featureless. What appears to have happened is that this spiral galaxy turned its star making inter-stellar material into stars very early in its life. Proof of this can be found in its spectrum, which is characterised by the presence of absorption lines rather than by emission features more typical of spirals with prominent arms and star forming regions. This is particularly noticeable in the Calcium H and K lines. NGC 2775’s spectrum is therefore dominated by the light from old cool stars, which themselves are characterised by absorption, not emission lines. This is more common in elliptical or SO type galaxies. It therefore has a smoothish appearance with faint spiral arms and little star formation now taking place.

Just above (north of) NGC 2775 there is a tiny background group of 4 or 5 galaxies.

Image Details

  • Dates: 18th March 2015
  • Telescope: RCOS 12.5 inch at f/9 and Takahashi FSQ106N
  • Camera: Apogee Alta U9 and Canon 60D
  • Exposure: Luminance - 10 x 20 mins IDAS-P2 - RGB 15 x 10 mins (Tak)


NGC 2775
H I   2
UGC 4820
PGC 25861

Catalogue position for epoch J2000.0
Right ascension:  09h 10m 20.5s
Declination:          +7° 02' 19"

Constellation: Cancer

Object information:
Magnitude: 10.1
Size: 5.0’ x 4.0'
Position angle: 155°
Object classification: Sa      
NGC Description:   considerably bright, considerably large, very gradually very suddenly much brighter towards the middle, resolvable - mottled
Note: in group with NGC2777 and NGC2773


NGC 2775

NGC 2775

7th APRIL 2015

Born Again Planetary Nebula, Abell 30


Very easy to locate, just south-east of the Beehive Cluster in Cancer but boy is it faint. The detail is in the OIII band but my camer's senstivity is very poor here. I could have done with running longer but after 5 nights I decided enough was enough.

Headlined by Nasa as the "Born Again Planetary Nebula" in the press release accompanying their iamge (right) in 2012. In reality most planetary nebulae go through several ejection phases so why, when this one was discovered to have had 2 discrete events it was such a big deal - who knows? The Born Again name actually seems to originate with Wesson et al in 2003 and Nasa just latched on to it.

In the Nasa/ESA image (right) they have reversed the colours. Hydrogen is blue and Oxygen is red. Until I found this out I couldn't come to terms with what my image was showing!!!!

Image Details

  • Dates: 16th & 21st February, 13th, 14th & 17th March 2015
  • Telescope: RCOS 12.5 inch at f/9
  • Camera: Apogee Alta U9
  • Exposure: 8 hours total: Ha - 11 x 20 mins, OIII - 13 x 20 mins



Abell 30

15th MARCH 2015

Planetary Nebula Abell 13


Appropriately numbered no. 13 - this object took 3 nights and 4 different filters to record it! According to Frew et al. (2012) "A catalogue of integrated H fluxes for 1,258 Galactic planetary nebulae" this PN is strongest in NII rather than in H-alpha. An ultra-narrowband H-alpha filter is not therefore ideal but one that includes NII as well will do best. The central star is catalogued as magnitude 18.8. However, it appears to be predominantly violet in colour as it did not record either with the OIII or H-alpha filters - I had to shoot an extra sequence of luminance images with a filter (IDAS-P2) passing violet in order to record it. I guess this will be a difficult object visually as there was litte OIII and H-beta will probably be weak.

Type of object: Planetary nebula PK 204-8.1
RA (J2000.0): 06h 04m 48.0s Dec (J2000.0): +3° 57' 00"
Constellation: Orion
Magnitude: 15.3
Size: 2.9'x2.2'
Magnitude of central star: 18.8

Image Details

  • Dates: 6th, 16th, & 21st February 2015
  • Telescope: RCOS 12.5 inch at f/9 and Takahashi FSQ106N
  • Camera: Apogee Alta U9 and Canon 60D
  • Exposure: Ha - 10 x 20 mins, OIII - 4 x 20 mins, IDAS-P2 - 4 x 20mins (RCOS); RGB (UHC filter) - 20 x 10 mins (Tak)



Abell 13


22nd FEBRUARY 2015

Planetary Nebula HaWe 2 (Sh2-200)


This object was catalogued by Sharpless as SH2-200 probably on the basis of the fainter outer (red) halo but it is in all probability a planetary nebula. This was first recognised by Hartl & Weinberger in 1987 in their paper "Planetary Nebula of low surface brightness: Gleanings from the POSS". It was no2 in their list so its name is generally abbreviated to HaWe 2. Their description is as follows:

No. 2 (138 + 04°1) : This object, listed as Sharpless 200, appears as a relatively large, slightly deformed ring in E (Blue), fainter and more disk-like in 0 (Red). Most remarkably, there appears to be an extended halo around the PN with a diameter six times as large as the central nebula ; note that the halo's size would then amount to 0.4, that is 4 pc at a distance of 580 pc ! The brightest part in the south- east of the halo has a red surface brightness of only ---- 24715. Although there is no visible blue central star, we suggest that this is a PN due to its enormous brightness in OIII according to the Emission Line Survey of Parker et at (1979) ; the halo, however, is not detectable there. A detailed study of nebula and halo is needed.

This object is faint and despite taking four years to get luminance and colour I still don't really have enough signal to do it justice.

Image Details

  • Dates: 11th January 2011 & 1st February 2015
  • Telescope: RCOS 12.5 inch at f/9 and Takahashi FSQ106N
  • Camera: Apogee Alta U9 and Canon 60D
  • Exposure: HaHaGB with Luminance and R, Ha - 8 x 20 mins, GB - 20 x 10 mins





8th FEBRUARY 2015

Planetary Nebula Kahoutek K2-1 (PK 173-5.1)
Fleur de Lys Nebula(?)


Another object brought to my attention by the big Dob boys - this time by Owen Brazell. He had seen this nebula several years ago and thought it would make a good a target. It was categorised as "status not clear" by Zijlstra et al. (1990A&AS...82..273Z). However, It has a strong OIII signal so is, in all probability, a planetary nebula. It does though have a very untypical appearance. If I was prone to naming objects then perhaps the Fleur de Lys Nebula would be apt. It is located in Auriga and its magnitude is given as 12 - it is surprisingly bright. The magnitude of its central star is given as 18.2 or 18.8 depending on which catalogue you consult.

This object deserves to be better known but for some reason some catalogues record its position incorrectly. Both Skymap and The_Sky6 plot this object in the wrong position so if you load a DSS image to check it out then nothing is visible. I guess many must have been put off looking for it by this error.

Kahoutek is, of course, best remembered for his (in)famous comet for which spectacular things were predicted. The reality was somewhat disappointing and a very insignificant comet was actually observed. In later years Kohoutek worked in observatories in Spain and Chile specialising in planetary nebulae.

Image Details

  • Dates: 18th January 2015
  • Telescope: RCOS 12.5 inch at f/9 and Takahashi FSQ106N
  • Camera: Apogee Alta U9 and Canon 60D
  • Exposure: Luminance OIII - 9 x 20 mins, RGB - 18 x 10 mins





1st FEBRUARY 2015

M38 and Abell 9


Brought to my attention by Andrew Robertson, who was struggling to see this faint planetary nebula with his big Dobsonians. This image was subsequently posted on the Deep Sky Forum by Owen Brazell to see if anyone had succeeded visually and if so, with what aperture. It is pretty faint and the OIII is weak so visually it will be a very tough target.

Little published information for this planetary nebula (PK 172+ 0.1) and about all I could find is

Magnitude Nebula: 18.9
Magnitude Central Star: 23.5

It was also flagged up as a "possible" planetary nebula as if there was some doubt. However, in my image at least, it looks like a planetary nebula so Abell was right to include it. It is amazing he spotted something so small and faint.

Image Details

  • Dates: 30th December 2014
  • Telescope: RCOS 12.5 inch at f/9 and Takahashi FSQ106N
  • Camera: Apogee Alta U9 and Canon 60D
  • Exposure: Luminance Ha - 13 x 20 mins, RGB - 26 x 10 mins



M38 and Abell9


22nd JANUARY 2015

Comet Lovejoy (C/2014 Q2)

Switched to a much wider field of view and broader light pollution filter. The clouds cleared quite late so shot when past the meridian and low so quite a bit of light pollution to remove.

Image details:

  • Date: 18th January 2015
  • Telescope: Pentax 50mm lens at f/4 and Bolton Tracker
  • Camera: Canon 40D
  • Exposure: 17 x 5 mins with IDAS-P1 filter
  • Lovejoy

    Comet Lovejoy


    20th JANUARY 2015

    Comet Lovejoy (C/2014 Q2)

    With just a short period forecast between clouds I didn't have much time to prepare for this image. I underestimated the tail length and used the wrong filter. The Tak was already loaded with a UHC clip filter for my next target and is not ideal - hopeless really - for comets. I should have switched to the 200mm lens and a broadband LPR filter. In the end I got just under an hour before the clouds returned.

    Image details:

  • Date: 16th January 2015
  • Telescope: Takahashi FSQ106N
  • Camera: Canon 60D
  • Exposure: 11 x 5 mins with UHC filter
  • Lovejoy

    Comet Lovejoy


    11th JANUARY 2015

    Sharpless Sh2-187


    This young star formation/ HII region is most likely ionised by a B0 class star (star 4 - see right) and is surrounded by a 4600 solar mass molecular cloud. It is partially obscured by the Lynds dark nebula LDN 1317 and contains the infrared star cluster BDS2003. (Ref: Galaxy Map). It has its own "trapezium" - stars 4, 5, 6 & 7 (see right).

    The definitive research into this object was carried out by Joncas, Durand and Roger (1992) and they concluded:

    1. Star 4 was probably the ionising star.

    2. Sh187 is 100,000 to 200,000 years old.

    3. We are actually only observing visually about 3% of the HII present.

    4. There is an HI disassociation area around the HII region.

    5. Sh187 resides in relatively "quiet" area of the local arm with no supernova remnants or OB associations.

    6. It could eventually produce massive stars.

    Located in Cassiopeia but not the brightest of Sharpless objects so I pressed on imaging for 5 hours. Only 152 Sharpless Objects still to do!

    Image Details

    • Dates: 3rd & 5th December 2014
    • Telescope: RCOS 12.5 inch at f/9 and Takahashi FSQ106N
    • Camera: Apogee Alta U9 and Canon 60D
    • Exposure: Luminance - 15 x 20 mins, RGB - 30 x 10 mins


    Figure 1: Joncas, Durand & Roger, 1992 - Central region with star 4 believed to be the ionising star of the nebula.



    4th JANUARY 2015

    Dwarf Galaxy, IC 1613


    IC 1613 (Caldwell 51) is an irregular dwarf galaxy in the constellation Cetus just below the star 26 Ceti. It was discovered in 1906 by Max Wolf

    IC 1613 belongs to the Local Group and is approximately 2.3 million light years distant. This is slightly nearer than M31 and is possibly a satellite of it. In 1928 Water Baade recognized this galaxy as a member of the Local Group because it could be resolved into individual stars using the Mount Wilson 100" reflecting telescope. He also could find no bright globular clusters and this is still true today.

    Its importance lies in the calibration of the Cepheid variable period luminosity relationship for estimating distances as it has many of these variables.

    If you suffer from light pollution, then this is one of most difficult of galaxies to image - its very low surface brightness and low altitude mean it is never going to be spectacular for us. However, there is a slight suggestion of a bar running 2:00 o'clock to 8:00 o'clock. In the top right hand corner of my image is a short trail of the asteroid Sara (533) at magnitude 14.8.

    Image Details

    • Dates: 27th & 30th November 2014
    • Telescope: RCOS 12.5 inch at f/9 and Takahashi FSQ106N
    • Camera: Apogee Alta U9 and Canon 60D
    • Exposure: Luminance - 9 x 20 mins, RGB - 19 x 10 mins


    IC 1613

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