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INTRODUCTION

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 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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3rd September 2020

Compact Galaxy Group Hickson 68

 

This Hickson group consists of 5 concordant galaxies with distance of around 120 light years. However, it would seem this group is a lot more complex with many many more members and not as compact as Hickson thought ref: MIDLIFE CRISES IN DWARF GALAXIES IN THE NGC 5353/4 GROUP R. Brent Tully and Neil Trentham 2008. Not the easiest of papers to read but it would appear that what look like faint backround galaxies are probably dwarf galaxies belonging to the group.

The interacting galaxies are NGC 5353 and 5354 - the barred spiral is NGC5371.

 

  • Dates: 19th April 2020
  • Telescopes: RCOS 12.5 inch at f/9 & Takahashi FSQ106
  • Cameras: Apogee Alta U9 and Canon 60D
  • Exposures: Luminosity 10 x 10 mins + RGB (Tak) 20 x 5 mins.
 

 

H68

Hickson 68



 

??th July 2020

The Cocoon Galaxy, NGC4490 & 4485

 

The closely interacting galaxies NGC 4485 and NGC 4490 are members of the NGC 4631 group of galaxies. NGC 4490 is a late-type spiral galaxy type SB(s)d with its companion NGC 4485 an irregular galaxy type IB(s)m. Their masses differ by factor of 4.

When I was processing my image I noticed a faint feature to the east (left) of NGC4490. At first I was unsure as to whether it was real or as a result of light pollution. It turned out to be real and was discovered by Elmegreen et al in 1998. To quote from her paper "A faint feature on the southeast side of NGC 4490 has been revealed by our B- and I-band observations; arm-interarm contrasts show that it is tidal in origin. The luminosity of the tail implies a total mass of about 4 x10^7 M The average tail color is the same as the color of the outer disk of NGC 4490, which supports the conclusion that it is tidally sheared material." Figure 3 from the paper is shown right.

Ref: OBSERVATIONS OF A TIDAL TAIL IN THE INTERACTING GALAXIES NGC 4485/4490, Elmegreen et al, 1998

 

  • Dates: 19th April 2020
  • Telescopes: RCOS 12.5 inch at f/9 & Takahashi FSQ106
  • Cameras: Apogee Alta U9 and Canon 60D
  • Exposures: Luminosity 10 x 10 mins + RGB (Tak) 20 x 5 mins.
 

fig3

cocoon galaxy

Cocoon Galaxy



 

20th July 2020

Comet Neowise - 20th July 2020

 

Could only see this spectacular comet from my upstairs bedroom window as it was quite low in the NNW. The camera (undriven) was simply sat on the windowsill- I did open the window first. Because the sky is so bright at this time of year in northern England only 3-4 second exposures were possible. Nevertheless it was enough to record the comet and its tail.

 

  • Dates: 23:45 BST on 20th July 2020
  • Telescopes: None
  • Cameras: Canon 60D + 50mm lens @f/2.8
  • Exposures: 20 x 3 secs
 

 

neowise

Comet Neowise



 

??th May 2020

The Mice, Interacting Galaxies NGC 4676-1 & 4676-2

 

Believed to be similar to what will happen to us when the Andromeda Galaxy and the Milky Way collide. These two mighty galaxies have already had one pass through each other, which has produced the long streamers or tails - hence their common name. In the future hey will collide again before merging into a single galaxy. There are computer simulations of galaxy collisions that mimic accurately the shapes we see in reality.

NGC 4676 lies about 300 million light-years away in the constellation Coma Berenices and the pair are likely members of the Coma Cluster of Galaxies.

 

  • Dates: 13th & 15th April 2020
  • Telescopes: RCOS 12.5 inch at f/9 & Takahashi FSQ106
  • Cameras: Apogee Alta U9 and Canon 60D
  • Exposures: Luminosity 21 x 10 mins + RGB (Tak) 41 x 5 mins.
 

 

the mice

The Mice



 

5th July 2020

Palomar 3

 

Not the most spectacular of globular clusters and although listed as 14.26 mag in reality it is much fainter as its brightest stars are only mag 18. It is one the most remote of the Milky Way globular clusters at over 300,000 light years and it is receding from us at 83.4 km per second - so getting more remote by the second!

It has been discovered no less than 3 times! First by A.G. Wilson and W. Baade in 1952. It discovered for a second time by A.G. Wilson in 1955 and named by him the Sextans Globular Cluster. Finally and also in 1955, by G.O. Abell who was unsure as to what it was and classified it as a nearby dwarf galaxy, elliptical or spheroidal type, named the Sextans C system. We now know it is a globular cluster and was included as one of the 15 Palomar Globular Clusters.

Palomar 3 is located only 4 degrees from the Sextans Dwarf galaxy, which was only discovered in 1990 - long after Pal 3. They are both at similar distances but probably not associated because of markedly different radial velocities.

  • Dates: 22 March, 14 & 16th April 2020
  • Telescopes: RCOS 12.5 inch at f/9 & Takahashi FSQ106
  • Cameras: Apogee Alta U9 and Canon 60D
  • Exposures: Luminosity 24 x 10 mins + RGB (Tak) 44 x 5 mins.
 

 

pal3

Pal 3



 

21st June 2020

Spiral Galaxy, M106

 

M106 (NGC 4258) is one of the largest and brightest nearby galaxies very similar in actual size and luminosity to the Andromeda Galaxy. It was discovered by Pierre Méchain in 1781.

M106 contains an active galactic nucleus (AGN) and these days is classified as a type 1.9 Seyfert. It is perhaps most famous for the presence of a water megamaser. Observiations of this enabled the mass of its central black hole to be calculated and also permitted its distance to be determined independently of other standard methods. It is 23 million light years distant. The galaxy to its right is NGC 4217, which is more than likely a companion

M106 also has another hidden feature namely twin powerful jets in its central region- see right. Reference: Jet-related Excitation of the [C II] Emission in the Active Galaxy NGC 4258 with SOFIA P. N. Appleton et al. 2018.

 

  • Dates: 26th & 27th March 2020
  • Telescopes: RCOS 12.5 inch at f/9 & Takahashi FSQ106
  • Cameras: Apogee Alta U9 and Canon 60D
  • Exposures: Luminosity 23 x 10 mins + RGB (Tak) 47 x 5 mins.

 

 

 

 

 

 

 

 

Figure from Appleton et al., 2018

jets

m106

M106



 

1st June 2020

The Whirlpool Galaxy

 

I had shot the Whirlpool Galaxy in 2009 and 2011 but using light pollution filters so the colours were not quite right. It was time to try again but without filters. The resulting light pollution in the images was trickier to remove but the colours were much more realistic.

This was the first spiral galaxy or rather spiral nebula to be observed. In 1845, William Parsons, 3rd Earl of Rosse, using the giant 72-inch (1.8 m) reflecting telescope at Birr Castle, Ireland, discovered the spiral structure. His famous drawing is right. He even recorded the second galaxy. Computer similations of the two galaxies interacting faithfully reproduces the complex streamers and tails visible in the image below.

Today M51 is classed as a Seyfert Type II galaxy and is around 23 million light years distant.

  • Date: 8th & 11th April 2020 + Hydrogen alpha (Ha) from 2nd April 2009
  • Telescopes: RCOS 12.5 inch at f/9 & Takahashi FSQ106
  • Cameras: Apogee Alta U9 and Canon 60D
  • Exposures: Luminosity 17 x 10 mins + Ha 15 x 10 (2009) + RGB (Tak) 28 x 5 mins.
 

lord rosse

M51

M 51



 

17th May 2020

Barred Spiral Galaxy NGC 2903

 

A return to serious imaging! A barred spiral galaxy thought to be similar to our Milky Way but with one strange difference. It is still forming new globular clusters. The Milky Way's globular clusters, on the other hand, are some of the oldest objects in the galaxy.

Located in the constellation Leo and NGC 2903 lies some 30 million light-years away. It was discovered by William Herschel on 16th November 1784.

Image Details

  • Date: 20th March 2020
  • Telescopes: RCOS 12.5 inch at f/9 & Takahashi FSQ106
  • Cameras: Apogee Alta U9 and Canon 60D
  • Exposures: Luminosity 17 x 10 mins + RGB (Tak) 34 x 5 mins.
 

 

ngc2903

NGC 2903



 

7th May 2020

Venus

 

Venus has been a spectacular evening object this spring so decided it was about time to take an image - actually a webcam video. 

Elevation was around 20 degrees so used my Atmospheric Dispersion Corrector with the prism spacing set at 31.5mm. No colour correction was needed for this image. It really does work.

Image Details

  • Date: 6th May 2020 - 21:30 BST
  • Telescope: Celestron 8-inch SCT at f/20 + ADC
  • Cameras: Microsoft Webcam
  • Exposures: best 900 from 1800 frames shot at 30 frames per second
 

 

venus-2020

Venus



 

1st May 2020

I see 37 or NGC2169

 

A shocking night with too many clouds so tried something bright. In 3 hours only managed to get 18 x 2-minute exposures - the rest were ruined by clouds.

The famous asterism is sometimes referred to as IC37 meaning "I see 37".

This asterism is a true open cluster and is located in Orion. It was possibly discovered by Hodierna but more certainly by William Herschel on 15th October 1784. Its distance is around 3600 light-years with a diameter of about 7 arc minutes and a total brightness of 5.9 magnitudes. The brightest of its about 30 stars is around magnitude 7, the hottest of spectral type B1, indicating an age of about 50 million years.

Image Details

  • Date: 1st March 2020
  • Telescopes: RCOS 12.5 inch at f/9 & Takahashi FSQ106
  • Cameras: Apogee Alta U9 and Canon 60D
  • Exposures: Luminosity 18 x 2 mins + RGB (Tak) 18 x 2 mins.
 

 

NGC2169

NGC 2169



 

19th April 2020

Open Clusters M35 & NGC2158

 

I was getting desperate - so many cloudy nights that when a chance of few gaps came along I went for it. Lost a lot of expousres to the clouds but managed to get 11 that were OK. Just used the Tak, it wasn't worth setting up the RCOS on such an iffy night.

Bright blue stars frequently distinguish younger open clusters. M35, on the upper left, is relatively nearby at 2800 light years distant, relatively young at 150 million years old (McNamara et al. 2011)with about 2500 stars covering a volume 30 light years across. The much older and more compact open cluster, NGC 2158, is at the lower right. The latter is four times more distant than M35, over 10 times older at 2 million years old (Carraro et al. 2002), and much more compact with many more stars in roughly the same volume of space. M35 is typically diffuse but NGC 2158 is very dense and was once believed to be a globular cluster.

 

Image Details

  • Date: 27th February 2020
  • Telescopes: Takahashi FSQ106
  • Cameras: Canon 60D
  • Exposures: 11 x 4 mins with no filter.
 

 

M35

M35 and NGC 2158



 

5th April 2020

Spiral Galaxy NGC 2403

 

My first image of 2020 after an 8 week cloud-out! Must be he worst winter for astronomy on record. I first saw this relatively bright galaxy with my homemade 6 inch Newtonian over 50 years ago ... but there was much less light pollution in those days.

NGC 2403 is a SAB(s)cd LINER type spiral galaxy in the constellation Camelopardalis. It is an outlying member of the M81 Group and is round 8 million light-years distant. It is similar to M33, being about 50,000 light years in diameter and containing many star-forming H II regions.

The H I Nearby Galaxy Survey (THINGS) produced rotation curves for several nearby galaxies including NGC 2403. Their rotation curve is shown right. It is typically "flat" i.e. it does not drop off with distance from the centre. This is taken to mean the presence of a dark matter halo. Reference: HIGH-RESOLUTION ROTATION CURVES AND GALAXY MASS MODELS FROM THINGS - W. J. G. de Blok, F. Walter, E. Brinks, C. Trachternac4, S-H. Oh, and R. C. Kennicutt Jr.. Published 2008).

Image Details

  • Date: 13th February 2020
  • Telescopes: RCOS 12.5 inch at f/9 & Takahashi FSQ106
  • Cameras: Apogee Alta U9 and Canon 60D
  • Exposures: Luminosity 20 x 10 mins + RGB (Tak) 40 x 5 mins.
 

Rrotation curve

Rotation Curve for NGC 2403, ref: Blok et al., 2008.

ngc2403

NGC 2403



 

27th March 2020

Comet Atlas

 

My first shot of this new comet. It wasn't supposed to be spectacular but brightened considerably approaching the Sun. Hopefully it could be even brighter in April/May perhaps easy in binoculars. It already had a reasonable tail when I imaged it. The image is centred on 21:00 GMT.

Latest April News: the comet appears to be fading so perhaps will not become spectacular after all

Image Details

  • Date: 25th March 2020
  • Telescopes: RCOS 12.5 inch at f/9 & Takahashi FSQ106
  • Cameras: Apogee Alta U9 and Canon 60D
  • Exposures: Luminosity 24 x 4 mins + RGB (Tak) 26 x 4 mins.
   
c-atlas

Comet Atlas -25th March 2020



 

1st March 2020

Andromeda 1

 

You would have thought Andromeda I would be the Andromeda Galaxy (M31) but not so. It is the first of several dwarf (dSph) satellite galaxies of M31. Discovered in 1970 by Sidney van den Bergh with the Mount Palomar 48-inch Schmidt Telescope, which gives you some idea that it must be faint - and it is! A more recent study by Pritzl et al., "The Dwarf Spheroidal Companions to M31: Variable Stars in Andromeda I and Andromeda III",May 2005 measured variable stars in the galaxy - these were mighty faint at 24 and 25th magnitude. The used Hubble Space Telescope images for this. The distance to the galaxy is around 2.6 million light years (NED) and it lies to the south of M31.

Image Details

  • Date: 3rd December 2019
  • Telescopes: RCOS 12.5 inch at f/9 & Takahashi FSQ106
  • Cameras: Apogee Alta U9 and Canon 60D
  • Exposures: Luminosity 23 x 10 mins + RGB (Tak) 38 x 6 mins.
   
andromeda 1

Andromeda 1



 

9th February 2020

Caroline's Rose, NGC 7789

 

This must have been the worst winter ever in Lancashire for clear nights. It is 2 months now since a proper Moon-free clear night!

One the best open clusters missed by Messier. It is faint but when you locate it is obvious. We had a splendid view of it this year at the Kelling Heath Starparty through the 8-inch Binocular Telescope. It is old, for an open cluster, at 1.6 billion years so its more massive stars have had time to age and become yellow/red giants. It was this what attracted me as shooting without yellow-blocking filters should reveal this cluster at its best. I wasn't disappointed.

Located in Cassiopeia tis cluster was discovered by Caroline Herschel in 1783. Her brother William Herschel included it in his catalog as H VI.30. It is therefore one the few deep-space objects dicovered by a lady. It is around 8,000 light years away and thanks to Wu Zhen-Yu1, Du Cui-Hua, Ma Jun and Zhou Xu, we know its mass to be approximately 6600 times that of the Sun (ref: Mass of Open Cluster NGC 7789, 2009).

Because of it size I had to use a two panel mosaic to fit it all in.

Image Details

  • Date: 30th November 2019
  • Telescopes: RCOS 12.5 inch at f/9 & Takahashi FSQ106
  • Cameras: Apogee Alta U9 and Canon 60D
  • Exposures: Luminosity 2 x 16 x 5 mins + RGB (Tak) 35 x 5 mins.
   
 
n7789 -rcos

Caroline's Rose - close-up

n7789 tak

Caroline's Rose - widefield


 

12th January 2020

Spiral Galaxy M74

 

This would be an even more severe test for imaging without a filter - M74 is notoriously faint and never rises that high over Lancashire. Because of it being of low surface brightness I upped the exposures. Yes there was more signal but the light pollution was horrendous making processing very tricky indeed.

Sometimes referred to as the Phantom Galaxy as it is probably the most difficult Messier object for visual astronomers. I have failed to see it from Lancashire with my 12.5inch telescope. It is a classic spiral galaxy in the constellation Pisces and is at a distance of around 32 million light-years. It is the brightest member of the M74 Group of 5–7 galaxies that also includes the peculiar spiral galaxy NGC 660 and UGC1176 & 1171. The latter 2 were recorded with my widefield view with the Takahashi.

Image Details

  • Date: 29th November 2019
  • Telescopes: RCOS 12.5 inch at f/9 & Takahashi FSQ106
  • Cameras: Apogee Alta U9 and Canon 60D
  • Exposures: Luminosity 18 x 15 mins + RGB (Tak) 28 x 7.5 mins.
   
m74

M74



 

16th December 2019

The Deer Lick Group

 

Having been pleased with my first test in imaging without a light pollution filter I thought I would give it a harder test. NGC 7331 is nearly twice as far away as NGC6946 and much lower in the sky so light pollution would be worse.

Does the group look like the Deer Lick Mountains? I guess not. The explanation is they were observed from the dark skies of those mountains by Tom Lorenzin, author of 1000+ The Amateur Astronomer's Field Guide to Deep Sky Observing, and he gave them this name. They are not actually a true group. NGC 7331 at around 40 million light years is a foreground object with the other smaller galaxies much much further away at around 300 million light years.

Image Details

  • Date: 23rd, 27th & 28th October 2019
  • Telescopes: RCOS 12.5 inch at f/9 & Takahashi FSQ106
  • Cameras: Apogee Alta U9 and Canon 60D
  • Exposures: Luminosity 28 x 10 mins + RGB (Tak) 55 x 5 mins.
   
n7331

NGC 7331



 

3rd December 2019

The Fireworks Galaxy (NGC 6946)

 

After over 30 years of shooting with light pollution filters I decided to give a go without. With many street lights now converted to LED bulbs there is no longer much benefit in shooting with a filter that predominantly blocks yellow light (of sodium lamps). The light pollution will still be there but it is now spread across the spectrum. For my first test I chose an object near the zenith.

Named the Fireworks Galaxy because of the number of supernova it has produced in the last 100 years - namely 10. One every ten years might not sound a lot but actually that is exceptional. It is classed as a starburst galaxy so it is perhaps not surprising it produces so many supernova. About 25 million light years distant so relatively close to us but beyond our local group.

 

Image Details

  • Date: 21st & 23rd October 2019
  • Telescopes: RCOS 12.5 inch at f/9 & Takahashi FSQ106
  • Cameras: Apogee Alta U9 and Canon 60D
  • Exposures: Luminosity 22 x 10 mins + RGB (Tak) 35 x 5 mins.
   
n6946

NGC 6946



 

17th November 2019

The Blinking Nebula, NGC 6826

 

Although well placed in Cygnus this planetary is often overlooked for more famous Messier ones nearby. Its distictive green colour makes it ideal for viewing with the rods in our eyes. As these predominate away from the centre of our vision then the nebula appears brighter with averted vision. This is of course why it seems to blink - look direct and it goes fainter, look away and it gets brighter.

There is a superb Hubble image of this object featuring "fliers".

Image Details

  • Date: 31st August & 7th Septemberl 2019
  • Telescopes: RCOS 12.5 inch at f/9 & Takahashi FSQ106
  • Cameras: Apogee Alta U9 and Canon 60D
  • Exposures: Luminosity 12 x 15 mins & 6 x 2 mins + RGB (Tak) 19 x 10 mins.
   
blinking neb

NGC 6826



 

3rd November 2019

Spiral Galaxy, NGC 5248

 

The constellation of Bootes is not noted for deep sky objects (it does have a few pretty double stars) but there is one object worth searching out, the spiral galaxy NGC5248. It is bright (magnitude 10.3 and relatively large (7 x 5 arc-minutes). Its central core stands out and is even visible in good finderscopes.

It is generally classesd as a Sc or but more recently as a SABbc type. Recent rotational velocity studies reveal 2 circum-nuclear star forming rings. There is a Hubble Space Telescope image available but it doesn't cover the whole galaxy.

Image Details

  • Date: 29th April 2019
  • Telescopes: RCOS 12.5 inch at f/9 & Takahashi FSQ106
  • Cameras: Apogee Alta U9 and Canon 60D
  • Exposures: Luminosity 7 x 10 mins & 5 x 2 mins + RGB (Tak) 7 x 10 mins.
   
ngc5248

NGC 5248



 

27th October 2019

Elliptical Galaxy, NGC 4697

 

A classical E6 elliptical galaxy but it does have a weak disc within it, inclined at an angle of 10 degrees to our line of sight which is just about visible in my image. It is the centre of its own group of galaxies and is one of the many Virgo II Sub-groups, which form a southern extension of the Virgo Supercluster of galaxies. Suprisingly its distance is poorly known and a wide range of values have been proposed with 50 million light years being a middle average.

As part of the mm-Wave Interferometric Survey of Dark Object Masses (WISDOM) project, its supermassive black hole was estimated to be 130 million solar masses. This estimate was derived from observations with the Atacama Large Millimeter/submillimeter Array (ALMA) - reference Davis et al,. 2017.

Image Details

  • Date: 10th April 2019
  • Telescopes: RCOS 12.5 inch at f/9 & Takahashi FSQ106
  • Cameras: Apogee Alta U9 and Canon 60D
  • Exposures: Luminosity 16 x 5 mins & 5 x 2 mins + RGB (Tak) 16 x 5 mins.
   
ngc4697

NGC 4697



 

6th October 2019

The Ghost Of Jupiter, NGC 3242

 

A Planetary Nebula in Hydra. William Herschel discovered the nebula on February 7, 1785, and cataloged it as H IV.27. His son, John, observed it from the Cape of Good Hope, South Africa, in the 1830s, numbered it as h 3248 and included it in the 1864 General Catalogue as GC 2102. This became NGC 3242 in J. L. E. Dreyer's New General Catalogue of 1888.

The name Ghost of Jupiter was coined by the noted British observer, Admiral Smyth, in the 19th century and the name has stuck. He noticed the similarity in size to Jupiter itself but that it had a much fainter ghostly glow. Nevertheless it is one of brighter planetary nebula at 8th magnitude and if you can see the Ring Nebula (M57) you should have no trouble with this one.

The blue colour of C59 comes from the presence of doubly ionised oxygen but other gases are present in the nebula as well. Its distance is poorly determined but it is around 1500 light years.

Image Details

  • Date: 9th April 2019
  • Telescopes: RCOS 12.5 inch at f/9 & Takahashi FSQ106
  • Cameras: Apogee Alta U9 and Canon 60D
  • Exposures: Luminosity 12 x 5 mins & 5 x 2 mins + RGB (Tak) 12 x 5 mins.
   
ngc 3242

Ghost of Jupiter



 

15th September 2019

Edge-on Galaxy, NGC 4244

 

There are several slender edge-on galaxies in the Caldwell Catalogue and this one, NGC 4244 or Caldwell 26, is sometimes called the Silver Needle Galaxy. NGC 4244 is one of the thinnest of galaxies with no central bulge. It is incredibly needle-like with a length of nearly one third of a degree yet with a width of less than 2 arc-minutes.

This Sc (or Sd) spiral is much smaller than the Milky Way at 65,000 light-years across and lies around 13.'5 million light-years away. It has a falling rotational curve (Olling, 1996) so has little dark matter. There is a Hubble image available for this object.

 

Image Details

  • Date: 29th March 2019
  • Telescopes: RCOS 12.5 inch at f/9 & Takahashi FSQ106
  • Cameras: Apogee Alta U9 and Canon 60D
  • Exposures: Luminosity 8 x 20 mins & 5 x 2 mins + RGB (Tak) 16 x 10 mins.
   
n4244

NGC 4244



 

8th September 2019

The Coma Galaxy Cluster (Abell 1656)

 

The Coma Cluster (Abell 1656) is the largest in local area with around 10,000 members. The central galaxy is NGC4889, which is the galaxy left of centre in my image. This image is just the central part of this huge cluster but over 100 galaxies are visible here - 109 I make it.

The cluster is famous for the discovery of dark matter. It was unknown and unsuspected until the (controversial) Swiss-American astronomer Fritz Zwicky discovered that this cluster was unstable without a considerable amount of unseen mass to hold it together. This was in the 1930s and was largely ignored until further evidence for dark matter started piling up later in the 20th century.

A plot of the dark matter in the cluster is shown right with the central portion of the cluster inset to scale.

 

Image Details

  • Date: 28th March 2019
  • Telescopes: RCOS 12.5 inch at f/9 & Takahashi FSQ106
  • Cameras: Apogee Alta U9 and Canon 60D
  • Exposures: Luminosity 9 x 20 mins + RGB (Tak) 17 x 10 mins.
  darkmatter
N 4889

Coma Galaxy Cluster



 

25th August 2019

Spindle Galaxy, NGC 3115

 

This Spindle Galaxy (there are others), is a bright SO galaxy, i.e. a disc galaxy without significant spiral structure or dust lanes, located in the faint constellation of Sextans. It is seen almost exactly edge-on, hence its name. It is bright (mag. 8.9) but, more importantly, it has a high surface brightness making it an easy telescope object, even from urban skies. To record its centre exposures no longer than 2 minutes were required.

Thought to be several times bigger than our own Milky Way, galaxy NGC 3115 is composed of mainly of old stars. It now contains virtually no gas and very little is going on, apart from the stately orbits of its stars. However, its main claim to fame is that it is one of the first candidates for harbouring a black hole in its midst. It is now known of course that virtually galaxies harbour one at their centre.

 

Image Details

  • Date: 22nd March 2010 & 25th March 2019
  • Telescopes: RCOS 12.5 inch at f/9 & Takahashi FSQ106
  • Cameras: Apogee Alta U9 and Canon 60D
  • Exposures: Luminosity 6 x 20 mins & 5 x 2 mins + RGB (Tak) 13 x 10 mins.
   
Spindle galaxy

NGC 3115



 

5th August 2019

Barred Spiral Galaxy NGC 4236

 

This mostly blue barred spiral is not displayed at its best as it is almost exactly edge-on to our line of sight. Located in Draco it is part of the M81 group of galaxies. This group is one of those that would have long ago dispersed if it wasn't for the presence on dark matter holding the cluster together. NGC 4236 is thought to be around 14.5 million light years away.

 

Image Details

  • Date: 25th March 2019
  • Telescopes: RCOS 12.5 inch at f/9 & Takahashi FSQ106
  • Cameras: Apogee Alta U9 and Canon 60D
  • Exposures: Luminosity 8 x 20 mins + RGB (Tak) 16 x 10 mins.
   
ngc4236

NGC 4236



 

21st July 2019

The Cat's Eye Nebula, NGC 6543

 

Discovered by William Herschel on 15th Feb 1786, this planetary nebula was the first to have its spectrum was investigated by the English amateur astronomer William Huggins. He showed it was gaseous and nothing to do with planets at all. It is an emitter of hard X-rays which is an ongoing puzzle that has still to be resolved.

The famous Hubble Space Telescope image (right) is shown in false colour highlighting regions of high and low ionisation. Three images were taken, in filters isolating the light emitted by Hydrogen alpha at 656.3 nm, singly ionised nitrogen at 658.4 nm and Oxygen III at 500.7 nm. The images were combined as red, green and blue channels respectively, although their true colours are red, red and green. The image reveals two "caps" of less ionised material at the edge of the nebula. Filters than can distiguish between H-alpha and Nitrogen cost around £1000.

 

Image Details

  • Date: 25th, 27th February & 7th March 2019
  • Telescopes: RCOS 12.5 inch at f/9 & Takahashi FSQ106
  • Cameras: Apogee Alta U9 and Canon 60D
  • Exposures: Luminosity 11 x 20 mins & 10 x 1min + RGB (Tak) 12 x 10 mins & 22 x 5mins.
  hubble
Cat's Eye

Cat's Eye Nebula



 

30th June 2019

Hubble's Variable Nebula, NGC 2261

 

Edwin Hubble is famous for galaxies and proving that the universe was expanding so when he had first shot with the then new 200 inch Palomar telescope surely he would have chosen a galaxy. But no he chose this nebula. The same happened when he first tried the 100 inch telescope. You could say he had a bit of a fixation for this object!

The reason for that fixation was that it varied and not only that it varied at the speed of light. How could that happen? Nothing moves at the speed of light or well light does and that turned out to be the explanation.

The nebula emanates from the variable star R Monocerotis and is illuminated by it. The probable explanation of the variations is that dense clouds of dust near R Mon periodically block the illumination from the star. This casts varying shadows onto the nebula and shadows have no problems in moving at the speed of light.

Most images of this object show the nebula against a black sky. However. it is evident from the widefield view below that the surrounding sky is anything but black. Accordingly my main image below has retained the faint nebulosity around Hubble's Variable Nebula

I first imaged this object in 2001 and when I was comparing images I noticed a fast moving star - see animated image at the right. In Hubble's 1949 image this star is even further to the north (top).

Image Details

  • Date: 2nd February 2019
  • Telescopes: RCOS 12.5 inch at f/9 & Takahashi FSQ106
  • Cameras: Apogee Alta U9 and Canon 60D
  • Exposures: Luminosity 9 x 20 mins + 6 x 2 mins + RGB (Tak) 19 x 10 mins.
  moving star
ngc2261

Hubble's Variable Nebula

widefield

Hubble's Variable Nebula - widefield view


 

23rd May 2019

Diffuse Nebulae Messier 78 & NGC 2071

 

These two largely reflection nebulae but with a bit of hydrogen alpha thrown in for good measure are located in eastern Orion and very close to Barnard's Loop - see right. M78 is the lower nebula and NGC 2071 the upper one but they are clearly associated. They both belong to the Orion B molecular cloud complex which is about 1,350 light-years distant from Earth.

The Orion Molecular Cloud Complex is a star forming region with stellar ages ranging up to 12 million years. Two giant molecular clouds are a part of it, Orion A and Orion B. The stars currently forming within the Complex are located within these clouds. A number of other somewhat older stars no longer associated with the molecular gas are also part of the Complex, most notably the Orion's Belt (Orion OB1b), as well as the dispersed population north of it (Orion OB1a). The Complex is between 1 000 and 1 400 light-years away, and hundreds of light-years across. Reference Wiki.

 

Image Details

  • Date: 26th & 27th February 2019
  • Telescopes: RCOS 12.5 inch at f/9 & Takahashi FSQ106
  • Cameras: Apogee Alta U9 and Canon 60D
  • Exposures: Luminosity 11 x 20 mins + RGB (Tak) 21 x 10 mins.
  orion mini
m78

M 78



 

5th May 2019

Tau Canis Major Cluster, NGC 2362

 

How low can you go? At an elevation of just 10 degrees I was pushing my luck with this open cluster. I had had a try in 2010 and decided it was time to try again.

A fabulous open cluster when viewed with any optical aid but really needs to be seen from further south than Britain. It surrounds the 4.4 magnitude star Tau Canis Major, which lends the cluster its name. Having a bright star in the cluster adds a real touch of class! Binoculars show Tau CM and an unresolved haze. In a 6 inch (150mm) telescope the haze reveals itself to be a tight swarm of 25 stars, spread around Tau CM in a circle. In a bigger telescope it just gets better with about 50 stars visible in a 16 inch (more if the cluster is high overhead in your location) and Tau, which is a bit dazzling, has two bluish companions. Tau CM is located in the “tail” of Canis Major, 11.5° south-east of Sirius.

Image Details

  • Date: 22nd March 2010 & 25th March 2019
  • Telescopes: RCOS 12.5 inch at f/9 & Takahashi FSQ106
  • Cameras: Apogee Alta U9 and Canon 60D
  • Exposures: Luminosity 16 x 5 mins + RGB (Tak) 9 x 10 mins.
   
Tau CM Cluster

NGC 2362



 

23rd April 2019

Planetary Nebula Abell 4

 

Located close to the open cluster M34 in Perseus and widefield shots of the latter will more than likely have recorded this faint planetary nebula at the same time.

An object with virually no data - well professional research papers covering it. It is also erroneously catalogued as PGC 10427 i.e. a galaxy in some databases.

At only 22 arcseconds across it is pretty small but is actually quite bright at least in imaging terms. The galaxy that seemingly points towards it is 2MFGC 2191 (PGC 2201333) but is much fainter and I would estimate around mag 17 for its nucleus. There are several more galaxies in the area but with no redshift data it is hard to be sure they are associated. It would seem likely though as they are roughly of similar brightness and size.

Abell 4 is listed as mag 16.7 and its central as 19.4 which I would confirm as probably correct. My limit is around 21st mag and I have recorded stars much fainter than the central star so it does seem about right.

For shooting this object I did not use narrowband filters - no doubt an OIII filter would have shown the nebula well but suppressed the galaxy. As the pair make an interesting grouping a broadband filter was used to record both well.

 

Image Details

  • Dates: 9th & 27th January 2019
  • Telescopes: RCOS 12.5 inch at f/9 & Takahashi FSQ106
  • Cameras: Apogee Alta U9 and Canon 60D
  • Exposures: Luminosity 10 x 20 mins + RGB (Tak) 23 x 10 mins.
  abell 4 detail
abell 4

Abell 4 Planetary Nebula



 

29th March 2019

Polar Ring Galaxy, NGC 660

 

NGC 660 is located around 45 million light-years away and is one of a rare class of “polar ring" galaxies, i.e. it has a belt of gas and stars around its centre probably emanating from a collision with another galaxy about one billion years ago. It also has a LINER-type nucleus (low ionization nuclear emission-line region; Nagar, Falcke, Wilson & Ulvestad 2002). It is believed to contain an exceptionally large amounts of dark matter.

In 2012 a massive outburst ocurred at the centre of NGC 660 that was around ten times as bright as a supernova explosion. Observations at Jodrell Bank confirmed this burst to be caused by a massive jet shooting out of the supermassive black hole at the center of the galaxy (ref: A new period of activity in the core of NGC 660, Megan K. Argo et al., 2015). The jet was observed to have an apparent speed of 1.2x c, the speed of light. This is a line of sight effect and its actual velocity was close to, but of course less than, c.

The pair of galaxies at the botom have a common redshift so are probably an associated pair and lie at around 700 million light years.

Image Details

  • Dates: 1st January 2019
  • Telescope: RCOS 12.5 inch at f/9 & Takahashi FSQ106
  • Camera: Apogee Alta U9 & Canon 60D
  • Exposures: Luminosity 13 x 20 mins & RGB (Tak + 60D)) 24 x 10 mins
 
ngc 660

NGC 660



 

11th March 2019

Globular Cluster, Palomar 2

 

One the brightest (least faint) of the Palomar globular clusters and it actually looks like a globular cluster. However, it is a remote cluster and we view it through the plane of the Milky Way so it is heavily reddened and is probably te reason it took the Palomar Schmidt Camera to spot it. Film in those days was more sensitive to blue objects.

Pal 2 has the unique distinction of being the globular cluster located farthest on the sky from the Galactic center, it is in Auriga of all places. It is classed as an outer halo cluster and it is a pretty remote one at that. It's distance (ref: Harris etal. 1997) is around 110 million light years from the galactic centre. This gives a clue that is must be one of the larger Milky Way clusters.

Image Details

  • Date: 8th January 2019
  • Telescopes: RCOS 12.5 inch at f/9 & Takahashi FSQ106
  • Cameras: Apogee Alta U9 and Canon 60D
  • Exposures: Luminosity 11 x 20 mins + RGB (Tak) 24 x 10 mins.
 
pal2

Palomar 2



 

3rd March 2019

Comet Iwamoto

 

A comet discovered by a human being and not a robotic telescope! Japanese amateur Masayuki Iwamoto spotted it in Hydra on the night of 18th December 2018 at magnitude 12. It has a high orbital inclination which is perhaps why the professionals missed it.

Its closest approach to the Sun was on 7th February and its closest approach to Earth on 12th February. I caught it 13 days later by which time it had faded considerably. Still there is the suspicion of a tail on the comet's left (east) side.

Its highly eccentric orbit lasts 1,371 years and goes out to 245 AU from the Sun taking it beyond the Kuiper Belt. If you missed it this time it will return in 3390 AD.

Image Details

  • Date: 25th February 2019
  • Telescopes: RCOS 12.5 inch at f/9 & Takahashi FSQ106
  • Cameras: Apogee Alta U9 & Canon 60D
  • Exposures: Luminosity 20 x 5 mins & RGB 21 x 5 mins
 
iwamoto

Comet Iwamoto



 

1st March 2019

Globular Cluster, Palomar 1

 

Very poor weather in December meant it took 4 nights to get enough images for this very faint globular cluster. Positioned in the halo and possibly in the Outer Arm of the Milky Way galaxy. First discovered by George O. Abell in 1954 on the Palomar Survey Sky plates. Located in Cepheus.

Palomar 1 (Pal1) is a very odd globular cluster with a very young age - around 4-6 billion years (Sarajedini et al. 2007) - note this is even younger than previous estimates. It also has a high "metallicity" ie not formed from original pristine material. Its location is also a bit odd with extended tidal tails (ref: Niederste-Ostholt et al., 2010)) either side of the cluster centre, with roughly as many stars in the tails as in the central cluster region. Thoughts are that it may have been once associated with a dwarf spheroidal galaxy which was later destroyed by tidal forces.

 

Image Details

  • Dates: 3rd, 12th, 13th & 14th December 2018
  • Telescope: RCOS 12.5 inch at f/9 & Takahashi FSQ106
  • Camera: Apogee Alta U9 and Canon 60D
  • Exposures: Luminosity 20 x 20 mins + RGB (Tak) 43 x 10 mins.

 

 

 

 

 

 

 

 

 

 

 

Sloan SDSS Image

sloan image
pal 1

Palomar 1



 

7th February 2019

Mirach's Goblin

 

Mirach's Ghost (NGC404) is relatively well known but Mirach's Goblin has only recently (2016) been discovered although details were only published in 2018. It was discovered by an Italian amateur astronomer, Giuseppe Donatiello. This very faint dwarf galaxy is located about 1 degree south of Mirach - see widefield image below. It is more properly known as Donatiello 1 after its discoverer. Donatiello (the astronomer) was searching for faint tidal streams between M31 and M33 and spotted this faint smudge. It's distance and that of NGC404 are the same at 10 million light years so probably associated.

The deep image at right is by Martinez-Delgrado et al using the 3.58 metre telscope on La Palma. It looks like they were struggling with light over-spilling from nearby Mirach.

Reference: Mirach's Goblin: Discovery of a dwarf spheroidal galaxy behind the Andromeda galaxy - David Martinez-Delgado et al., 10 Oct 2018.

Image Details

  • Dates: 1st, 11th & 14th November 2018
  • Telescope: RCOS 12.5 inch at f/9 & Takahashi FSQ106
  • Camera: Apogee Alta U9 and Canon 60D
  • Exposures: Luminosity 18 x 20 mins + RGB (Tak) 34 x 10 mins.
italian image
goblin

Mirach's Goblin

ghst and goblin

Mirach's Ghost & Goblin - widefield



 

29th January 2019

Supernova 2019np in NGC 3254

Discovered by Koichi Itagaki on 9th Jan 2019 in the spiral galaxy NGC 3254 in Leo Minor. It is a classic type Ia and was discovered early - probably before its maximum. I estimate it to be around 14th mag on 27th January but my estimates are somewhat approximate as light pollution filters were used.

It appears to be located at the end of a spiral arm on the outskirts of the galaxy making it easy to spot and presumably it is not very obscured.

NGC 3254 has a redshift of 0.004 and is estimated to be around 100 million light years away. So the star exploded 100 million years ago!

Image Details

  • Dates: 27th January 2019
  • Telescope: RCOS 12.5 inch at f/9 & Takahashi FSQ106
  • Camera: Apogee Alta U9 and Canon 60D
  • Exposures: Luminosity 3 x 20 mins + RGB (Tak) 6 x 10 mins.
 
sn2019np

Supernova in NGC 3254



 

23rd January 2019

Mirach's Ghost, NGC 404

 

The instructions with my camera (Apogee Alta) strongly advises against shooting bright objects but I was determined to give this one a go. Yes there was a residual image that took some time to dissipate but it was a poor night so faint targets were not an option. The reflections from Mirach were troublesome but in the end were removable.

NGC404 is a nearby (10 mly) dwarf S0 galaxy almost certainly harbouring a Massive Black Hole (MBH). Massive in this case is relative as at 150,000 solar masses this makes it the galaxy with the lowest-mass central MBH known. A number of lines of evidence suggest that the putative MBH in the centre of NGC404 is currently accreting material so it is still active. This central activity has resulted in NGC404 being classed as a Liner (low-ionization nuclear emission line region) Galaxy and is the nearest known.

Image Details

  • Dates: 14th November 2018
  • Telescope: RCOS 12.5 inch at f/9 & Takahashi FSQ106
  • Camera: Apogee Alta U9 and Canon 60D
  • Exposures: Luminosity 12 x 5 mins & 16 x 15 secs + RGB (Tak) 14 x 5 mins.
ngc404 hst
ghost

Mirach and NGC404



 

11th January 2019

Open Cluster, Messier 34

 

A poor night and I wanted to check tracking which had been misbehaving recently so I chose a bright object - open cluster M34. The issue I was trying to overcome is the joystick hand control on the Paramount - it can stick slighly on and cause drift. Seemed ok tonight though. Must remember to give it a bang before the next time.

In cluster research, M34 is an important cluster with an age of 250 million years which places it between the Pleiades at 100 million years and the Hyades at 800 million years. Its distance is around 1500 light years. Despite its relatively young age it has 19 known white dwarf stars - giant stars that are reaching their end of their lives having already exhausted their hydrogen fuel.

Image Details

  • Date: 9th January 2019
  • Telescope: RCOS 12.5 inch at f/9 & Takahashi FSQ106
  • Cameras: Apogee Alta U9 and Canon 60D
  • Exposures: 8 x 5 mins (mono) and 8 x 5 mins (colour)
 
m34

Messier 34



 

1st January 2019

Clusters of Cassiopeia

 

Cassiopeia is really cluster land with over 100 of the open type. It was a windy night and with the Moon present a simple target of the open clusters around Epsilon and Delta Cassiopeia was the order of the day.

The prominent cluster is NGC 663 and this is the one you notice first if sweeping the area with binoculars. It stands out much more than M103 and many suspect that it is actually Messier's number 103. His description is not precise and either cluster matches his location but to me it has always seemed that the brighter NGC 663 is the much more likely candidate.

Two of the clusters are Caldwell Objects, NGC 663 and NGC 559.

Cluster IC 166 is heavily reddened - presumably by obscuration. It is pretty faint with only a couple of stars brighter than 15th mag (ref. Martin Burkhead). It is about 1 billion years old.

Image Details

  • Dates: 17th November 2018
  • Telescope: Canon 200mm lens at f/4.5
  • Camera: Canon 60D
  • Exposures: 32 x 5 mins
 
Cass Clusters

Cassiopeia Clusters



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