iBlog

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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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



 

15th December 2018

M77 and Supernova SN 2018ivc

 

47 million years ago in a galaxy far far away a star exploded. Its light has just reached Lancashire! It is close to the galaxy's centre so not easy to spot and the weather only allowed a few hazy shots last night. Inset is of my previous image of 10 years ago.

Update: it would appear that the supernova is no where near as bright as it should be (15th mag?) and this is put down to probable obscuration -it is after all very close the the centre of the galaxy.

Image Details

  • Dates: 14th December 2018
  • Telescope: RCOS 12.5 inch at f/9 & Takahashi FSQ106
  • Camera: Apogee Alta U9
  • Exposures: Luminosity 1 x 20 mins & 5 x 10 mins
 
m77 supernova

M77 and Supernova 2018



 

2nd December 2018

Globular Cluster M15

 

Whilst shooting the planetary nebula ngc7094 I couldn't resist the temptation to also shoot the nearby globular cluster M15.

Messier 15 is one of the brightest globular clusters in the northern sky and is home to around 100,000 stars. It is one of the most densely packed globulars in the Milky Way galaxy and is classed as 'core collapsed'. Whether it has a black hole at its centre is subject to much speculation in professional research papers. Even images taken with the Hubble Space Telescope were unable to resolve its dense core and solve the problem.

Image Details

  • Dates: 29th October 2018 (widefield view taken on 1st November)
  • Telescope: RCOS 12.5 inch at f/9 & Takahashi FSQ106
  • Camera: Apogee Alta U9 and Canon 60D
  • Exposures: Luminosity 13 x 10 mins + 3 x 60secs (for centre) + RGB (Tak) 15 x 10 mins.
m15

M15

ngc7094 & M15

NGC7094 & M15



 

21st November 2018

Planetary Nebula NGC 7094

 

There is growing evidence that planetary nebula are much more likely to form in binary systems. This would also explain how they can produce such a wide variety of morphologies. However, even so some shapes are so "messy" - as is the case with NGC 7094 - that perhaps triple or even multiple stars systems must be involved.

In a recent paper, Bear & Soker, place NGC 7094 in the category "Maybe shaped by a triple stellar progenitor" - see reference. They were not certain in this case as they though intereaction with the interstellar medium could have preduced the asymmetry. They concluded that according to their assumptions about 13%–21% of PNe have been shaped by triple stellar systems. They concluded "Although in some evolutionary scenarios not all three stars survive the evolution, we encourage the search for a triple stellar systems at the center of some PNe".

Ref: Planetary Nebulae that Cannot Be Explained by Binary Systems, Ealeal Bear and Noam Soker, 2017.

With virtually no Ha signal present I shot this nebula using an OIII filter only - the Takahashi providing the broadband colour.

Image Details

  • Dates: 18th & 28th October 2018
  • Telescope: RCOS 12.5 inch at f/9 & Takahashi FSQ106
  • Camera: Apogee Alta U9 and Canon 60D
  • Exposures: Luminosity (OIII) 16 x 20 mins + RGB (Tak) 30 x 10 mins.
pn 7094

Planetary Nebula NGC 7094



 

8th November 2018

Pegasus Dwarf Irregular Galaxy, DDO216

 

Known at PegDIG to professional astronomers, this dwarf galaxy is described as a "low-luminosity transitional-type" between dwarf spherical and dwarf irregular ie dSph/dIrr. It is part of the local group and is a distant satellite of M31. It was discovered in the 1950s on Palomar Schmidt plate by A.G. Wilson and is now known to be around 3 million light years away. It is somewhat unusual in that star formation has almost ceased despite still being gas rich - it has a 1:1 gas to stellar ratio. There is some evidence that it is rotating.

Recently (see reference) Hubble Space Telescope images have confirmed the presence of a substantial globular cluster (DDO216-A1) near the centre of the galaxy. It is relatively large with a mass of around 100,000 solar masses ie this makes it bigger than 90% of the Milky Way globulars. The PegDIG galaxy is the lowest luminosity local group galaxy to host such a large globular cluster. The Hubble images were able to identify RR variable stars (at around 25th to 26th magnitude!) enabling its distance to be confirmed and Its age be be estimated to be around 12.3 billion years.

The images right show the location of the globular. The top image is Cole et al's wider field negative image using the Hubble. The rectangle is the position of the Hubble colour image at the bottom. Cole et al. did not have north at the top so their images have been rotated accordingly. The middle image is a blow-up of my image. Originally I thought this must be the core of the galaxy and it was after digging through the research papers did I realise it was a globular cluster. The bottom image is a colour Hubble image again rotated to have north at the top and does begin to show that it really is a large globular cluster.

The tiny edge-on galaxy is way in the background and its resdshift (0.0689) indicates a distance of around 900 million light years.

PegDig is located just below the bottom of the Square of Pegasus.

Ref: Cole at al. "DDO216-A1: A Central Globular Cluster in a Low-luminosity Transitional-type Galaxy", 2017

 

 

Image Details

  • Dates: 9th October 2018
  • Telescope: RCOS 12.5 inch at f/9 & Takahashi FSQ106
  • Camera: Apogee Alta U9 and Canon 60D
  • Exposures: Luminosity (CLS) 9 x 20 mins + RGB (Tak) 18 x 10 mins.
hubble
peg dwarf gal

Pegasus Dwarf Galaxy



 

17th October 2018

Open Cluster, Messier 29

 

Located in Cygnus, this young open cluster does look to a certain extent like a smaller Pleiades. Strangely not many published images of this object - guess there are more spectacular objects around it.

Until very recently the distance and age of this cluster was very poorly known with widely varying estimates over the years. This changed in 2014 with the publication by Straizys et al., The Enigma of the Open Cluster M29 (NGC 6913) Resolved. The determined its distance to be 5,000 light years and its age 5 million years. The problem was complicated by the fact that not all stars here are actual cluster members. Of the 7 brightest stars, the blue one is a background blue giant and the "handle" star (top left) a foreground object.

To reduce the blooming (bleeding) from the bright stars I decreased my normal exposures from 20 mins down to 10 mins. I also shot half before a meridian flip and half afterwards so the blooms went in opposite directions.

Image Details

  • Dates: 10th October 2018
  • Telescope: RCOS 12.5 inch at f/9 & Takahashi FSQ106
  • Camera: Apogee Alta U9 and Canon 60D
  • Exposures: Luminosity (CLS) 12 x 10 mins + RGB (Tak) 12 x 10 mins.
M29

Open Cluster M29



 

10th October 2018

Escaping the Void, AlfaZoa J1952+1428

 

Our local group of galaxies and most of our neighbours form part of a remarkably flat structure known as the Local Sheet. This is actually a wall of the Local Void. The latter extends for 240 million light years with very little in it - certainly no big galaxies and probably containing a smattering of dark matter and occasional dwarf galaxies.

The Local Void is largely hidden from view being located behind the Milky Way. It pokes out either side just a bit into Aquila and Sagittarius. That explains why the name of this galaxy has Zoa in its title. ZOA of course stands for Zone of Avoidance - that part of the sky where galaxies appear to be absent because the Milky Way blocks our view. Radio telescopes on the other hand are able to detect galaxies behind our galaxy.

AlfaZoa is one of only 2 well established galaxies in the Local Void and was found as part of a ZOA radio survey by the Arecibo Radio Telescope. It was detected by is HI emission which actually extends much further out than its optical size.

Theory has it that voids expand and anything inside them will be rushing out to escape. This theory was recently proved to be correct (see reference). AlfaZoa is racing out of the void at 370 km/sec. It is a dwarf galaxy like Magellanic Clouds but around 100 times further away at 27 mly. This distance makes it very much towards our side of the void. It is can be found in Aquila.

The Hubble image was acquired over 4 orbits and was able to resolve its stars and enable the calculation of its distance.

Ref: Rizzi, Tully et al, Draining The Void, 2016.

 

Image Details

  • Dates: 6th October 2018
  • Telescope: RCOS 12.5 inch at f/9 & Takahashi FSQ106
  • Camera: Apogee Alta U9 and Canon 60D
  • Exposures: Luminosity (CLS) 8 x 20 mins + RGB (Tak) 5 x 10 mins.
hubble and dr
alfazoa

Alfazoa J1952+1428



 

3rd October 2018

Blazar BL Lacertae

 

The Observatory re-opened after an 18 month interruption. Boy was it difficult re-learning everything. What made it worse was the observatory computer had failed and all the systems had to re-loaded with of course all the correct parameters re-set. First target was therefore something easy!

It took many years for astronomers to work out what this object was - it has a featureless spectrum with no absorption or emission lines. Over the years ideas ranged from a peculiar variable star or even a planetary nebula (Arp) in our own galaxy. We now know it is a Blazar - a quasar where the jet from its central black hole is pointing straight at us. Key to this was determining its redshift but with that featureless spectrum is was very tricky. Only when the light from its centre was blocked was an elliptical galaxy with a red shift of 0.07 revealed. Its distance is around 900 million light years. It does vary in brightness over very short timescales but in my (raw) images it looks around magnitude 14.5.

Located in western Lacerta so we are looking very close to the plane of the Milky Way - hence the large number of foreground stars and faint nebulosity more evident in the wide field view. I didn't get BL Lac very central - lack of practice!

Image Details

  • Dates: 28th September 2018
  • Telescope: RCOS 12.5 inch at f/9 & Takahashi FSQ106
  • Camera: Apogee Alta U9 and Canon 60D
  • Exposures: Luminosity 6 x 20 mins + RGB (Tak) 12 x 10 mins.
 
bl lac

BL Lac - detail image

BL Lac

BL Lac - full frame image



 

12th June 2018

Jupiter - altitude 20 degrees

 

What could be better on a warm summer evening than to image Jupiter whilst sat in a deck chair!

Very low this year from Lancashire so the ADC (Atmospheric Dispersion Corrector) had to utilised and set to a spacing of 31mm. The webcam is a colour Microsoft webcam which gives a good image size with a focal length of 4 metres.

The Celestron C8 is getting on for 25 years old now but it is perfect for the solar system. It requires no heavy battery to carry out - it uses an internal 9v PP9 battery. I have an electric focuser fitted which makes planetary focusing a lot easier - or less hard. Polar alignment is always guessed and adjusted by kicking one the tripod legs. Fairly quick and requires no complicated app.

Images stacked using Registax 6 and sharpened using Iris wavelets.

Image Details

  • Date: 7th June 2018
  • Telescope: Celestron Celestar 8-inch SCT @ f/20 with ADC unit set to 31mm prism spacing.
  • Camera: Microsoft Lifecam Webcam
  • Exposure: 1500 frames of a 3000 frame video shot at 20 fps.
  adc
jupiter2018
Jupiter 7th June 2018


 

24th October 2017

Copeland's Septet (VV282, HCG57)

 

Discovered by Ralph Copeland in 1874 using the 6 foot "Leviathan of Parsonstown" telescope at Birr Castle, Ireland. He was assistant to Lord Rosse and rose eventually to be Astronomer Royal for Scotland.

It was a fortuitous discovery as he was actually looking for another "nebula" but had been given the wrong RA coordinates. He could see 7 nebulae (galaxies) hence septet but there are at least 8 probably 9 associated together - the galaxy marked with "?" has a matching redshift. He catalogued them in the wrong location and the original NGC had them as "non-existent". Fortunately this was subsequently corrected and Copeland given credit.

HCG NGC Mag (Aladin) Copeland's Description
a 3753 14.52 pB (pretty bright)
b 3746 15.01 pB
c 3750 14.91 pB
d 3754 15.06 pB
e 3748 15.77 pB
f 3751 15.23 F (faint)
g 3745 16.18 vF (very faint)
h 17.38 not seen
? 17.78 not seen

The distance to the group, based on their redshift and Ned Wright's calculator, is around 430 million light years.

Image Details

  • Dates: 2nd, 21st & 22nd April 2017
  • Telescope: RCOS 12.5 inch at f/9 & Takahashi FSQ106
  • Camera: Apogee Alta U9 and Canon 60D
  • Exposures: Luminosity 12 x 20 mins + RGB (Tak) 24 x 10 mins.
key
Hickson 57 - Key to members
deatil

Copeland's Septet - full resolution

copeland

Copeland's Septet - full frame image



 

23rd July 2017

Hickson 55 (VV172)

 

Discovered by the Russian astronomer Vorontsov-Veljaminov on POSS plates and he catalogued the group as VV 172. Burbidge took an interest in the group and the term galaxy chain was coined. The chain became famous however, in the debate over whether redshifts could be relied upon as distance indicators as the faintest member, second from the top (north) has a much greater redshift than the rest of the group. Arp included it in his catalogue as 329 and Hickson in his as 55.

The redshift debate has been long settled but an interesting research paper in 1995 "The nature of discordant redshift galaxies in compact groups" by Mendes de Oliveira proposed a novel, for then, solution as to why groups of galaxies often seemed to have a member with an anomalous redshift. The solution proposed was that the mass of the real group acts as a gravitational lens to magnify and brighten any possible background galaxy in the same line of sight. You would therefore produce more apparent discordant redshift members than pure chance would provide. Gravitational lensing is much more accepted now but for 1995 it was quite a novel explanation.

Image Details

  • Dates: 25th & 27th March 2017
  • Telescope: RCOS 12.5 inch at f/9 & Takahashi FSQ106
  • Camera: Apogee Alta U9 and Canon 60D
  • Exposures: Luminosity 13 x 20 mins + RGB (Tak) 26 x 10 mins.
 
H55

Hickson 55 - detail image

h55-full

Hickson 55 - full frame image



 

18th June 2017

The Owl and Hickson 50

 

The Owl Nebula, M97, points the way to several obscure objects. Just above it is a faint galaxy and just below it a faint nebula. A little further to the east (left) in the Hickson Galaxy Cluster HCG50.

HCG50 is the faintest and has the highest redshift of the 100 Hickson groups. The 5 galaxies form a ring and all have redshifts around z=0.14 although with a high velocity dispersion indicating the presence of dark matter. The redshifts indicate a light travel time of around 1.75 billion years.

Although certainly the faintest Hickson group their magnitudes are somewhat disputed. Catalogues place them around mag 18 to 19 but CCD imagers tend to suggest they are around 1 magnitude brighter. Old catalogue values can be blue biased as films were more sensitive to blue wavelengths. The obvious colour of the galaxies in my shot is certainly not blue so it is no surprise their blue mag is faint. CCDs on the other hand are more red sensitive. Either way a big Dobsonian will be needed to see them.

As is often the case with the Hickson groups, there are galaxies around around them and with similar brightnesses and colours. However, the two below (south and south-east in the enlarged image) have much lower redshifts but the double galaxy (upper right) does have a matching redshift so is probably associated.

Image Details

  • Dates: 23rd & 24th March 2017
  • Telescope: RCOS 12.5 inch at f/9 & Takahashi FSQ106
  • Camera: Apogee Alta U9 and Canon 60D
  • Exposures: Luminosity 13 x 20 mins + RGB (Tak) 26 x 10 mins.
hcg50
HCG50

The Owl and HCG50



 

14th May 2017

A Spiral Nebula, Sharpless Sh2-266

 

A very odd nebula and possibly one of the most distant HII regions from the centre of the galaxy. The spiral shape is believed to result from the intense stellar wind from a massive central star known as MW137. Initially thought to be a Herbig-Haro type star it was later found to be a supergiant Be type star by Estban et al. (1998). They concluded it was a "ring nebula", the first such known around a Be supergiant. Visually it looks more like a helix than a ring giving it its spiral appearance.

Located in Orion so often over-looked and ignored. There are many more famous objects nearby.

Image Details

  • Dates: 8th & 12th March 2017
  • Telescope: RCOS 12.5 inch at f/9 & Takahashi FSQ106
  • Camera: Apogee Alta U9 and Canon 60D
  • Exposures: Ha (RCOS) 13 x 20 mins + RGB (Tak) 28 x 10 mins.
sh2-66-detail
sh2-266

Sh2-266



 

1st May 2017

Sharpless Sh2-235

 

Close up view of Sharpless Sh2-235 taken with the 12 inch RCOS and has much more detail than is evident in the widefield view in my previous image below, which was taken with the 4 inch Tak. Also it becomes very obvious that this group (Sh2-231, 232, 233 & 235) is really all part of one giant nebula.

South of Sh2-235 is a tiny nebula previously erroneously classed as a planetary nebula (PN G173.7+02.7). This is actually an emission nebula (confirmed by Kohoutek in 2001) and is now sometimes classified at Sh2-235A.

Galaxy Map states "Infrared analysis using the Spitzer space telescope has found 86 young stellar objects within Sh 2-235. Sh 2-235 is ionised by the O9.5 V star BD +35 1201". This is the star just about dead centre of the nebula and image.

Image Details

  • Dates: 23rd, 25th & 28th January 2017
  • Telescope: RCOS 12.5 inch at f/9 & Takahashi FSQ106
  • Camera: Apogee Alta U9 and Canon 60D
  • Exposures: Ha (RCOS) 15 x 20 mins + RGB (Tak) 28 x 10 mins.
ah2-235

Sh2-235



 

16th April 2017

Sharpless Sh2-231, 232, 233 & 235

 

The Sharpless numbering system went a little awry here and the nebula are from left to right: Sh2-232, -235, -231 and -233 (the smallest). Sh2-235 is the brightest - my image doesn't really represent how faint some of these are - and has below it another tiny nebula previously classed as a planetary nebula (PN G173.7+02.7). This is actually an emission nebula and is now sometimes classified at Sh2-235A. There is a real planetary nebula within Sh2-232 - see right. The nebula in the top right hand corner doesn't seem to have a catalogue number. This grouping is located in Auriga.

The following is best information I could find and is from Galaxy Map:
Sh 2-231, Sh 2-232, Sh 2-233 and Sh 2-235 are within the giant molecular cloud, G174+2.5, at a distance of about 1800 pc. They form a complex of HII regions located together in the Perseus arm in the outer galaxy. Sh2-232 is described as a peculiar belted nebula and is ionised by two giant stars: the O9.5 III HD 37737 and an anonymous B0 II class star according to Avedisova. HD 37737 may be a runaway star and is a close binary with a period of 7.84 days.

Image Details

  • Dates: 23rd, 25th & 28th January 2017
  • Telescope: Takahashi FSQ106
  • Camera: Canon 60D
  • Exposures: 28 x 10 mins with UHC filter.

Close-up of planetary nebula in Sh2-232

Pu2

PN G173.5+03.2 (Pu2)

Sh231-5

Sh2-231, -232, -233, -235



 

26th March 2017

Trifid of the North, NGC 1579

 

Although sometimes referred to as the Northern Trifid Nebula it really doesn't compare to its southern namesake. It is in fact one of the oddest nebula there is. Often (wrongly) classed as an emission nebula because it is brightest in the red and H-alpha band. Sharpless even included it in his emission nebula catalogue as Sh2-222. It is actually a reflection nebula - ref: Herbig, Andrews & Dahm (AJ2004).

If it is a reflection nebula why is it predominently red? That question has made NGC 1579 one of the most studied of nebulae. It was the detection within it of the energising star LkHa101 (see right) that led to the explanation. The nebula is red because of interstellar extinction and the nature of the illuminating source. The theory is that the star LkHa101 is a hot massive star caught very early in its development - less than a million years old. It is surrounded by its own h-alpha emission nebula. It is the light from the latter that illuminates the nebula in h-alpha light. Herbig et al. concluded only when the star's nebula has dispersed will it become visible.

Image Details

  • Dates: 20th January 2017
  • Telescope: RCOS 12.5 inch at f/9 & Takahashi FSQ106
  • Camera: Apogee Alta U9 and Canon 60D
  • Exposures: Ha 14 x 20 mins + RGB (Tak) 28 x 10 mins.

 

LkHa101

Image centred on the energising star LkHa101 (not visible), which is located just north of the brightest star shown. Both images taken in red band.
Left is by Herbig
, Andrews & Dahm (2004) - 2.2 metre telescope Hawaii
Right is by DR (2017) - 0.31 metre telescope Lancashire

 

NGC1579

NGC 1579



 

5th March 2017

Planetary Nebula Baade 1

 

Very few images and virtually no data available for this planetary nebula. In addition several catalogues have this object's coordinates wrong. Most catalogue sizes are an underestimate too - they appear to just give the size of the central ring, not the outer halo. Below is Walter Baade's discovery paper published by the Astronomical Society of the Pacific. Surprisingly it is not the faintest of objects despite needing the 100 inch telescope to confirm it. It didn't need super long exposures for me to record it.

paper1935

Due east is a very faint galaxy - well faint in my narrowband image which is hardly ideal for galaxies.

Image Details

  • Dates: 4th, 13th & 14th January 2017
  • Telescope: RCOS 12.5 inch at f/9
  • Camera: Apogee Alta U9
  • Exposures: OIII 13 x 20 mins + Ha 9 x 20 mins.

 

Type of object: Planetary nebula

Other name: PK171-25.1

RA (J2000.0): 03 53 37

Dec (J2000.0): +19 29 39

Constellation: Taurus

Magnitude: 13.9

Size: 50" (estimated)

Magnitude of central star: 17.1

 

Baade 1

Baade 1



 

19th February 2017

Close encounter of the Planetary Nebulae kind - HFG1 & Abell 6

 

When I shot Abell 6 in 2013 I also shot a widefield view which picked up HFG1 as well. In fact it was how I first became aware of HFG1. So once I had returned for an image of HFG1 it was natural to put everything together in one image. It has ended up very much as "little and large". Their separation is a fraction under 40 arc-minutes. Due to the rapid motion of HFG1 this chance encounter won't last long - well on galactic timesales that is!

Image Details

  • Dates: 11th & 17th Decmber 2013 and 4th, 21st & 22nd December 2016, 1st & 2nd January 2017
  • Telescope: RCOS 12.5 inch at f/9 and Takahashi FSQ106N
  • Camera: Apogee Alta U9 and Canon 40D & 60D
  • Exposures: The background is 22 x10 mins with Tak 106/Canon 40D with the nebulae from the RCOS/Apogee images - total over 24 hours.

 

Abell6-HFG1

HFG1 and Abell 6



 

12th February 2017

Planetary Nebula HFG1

 

As planetary nebulae go this one is huge. So you would think its name must stand for Huge Friendly Giant 1. But no - it' is named after its discoverers Heckathorn, Fesen & Gull, who first spotted it in 1982.

Its central star is V664 Cas, which is a 14th mag variable. It comprises a very close pre-cataclysmic binary system with a period of around 14 hours and the main emission comes from a “hot” spot on the primary. Originally it was a 3 Solar mass star but has lost 2.4 solar masses to the nebula leaving its current mass as just 0.6 solar masses. It is moving fast towards the south-east (bottom left) leaving a trail behind it and creating a shock front on its leading edge.

This is the longest exposure I have managed at 20 hours total which gives a clue that this object is faint. The central portion can be recorded pretty easily but the OIII ring/shock front is just about at my limit. Really to do it justice a dark sky and ultra-narrow band filters are needed.

Image Details

  • Dates: 4th, 21st & 22nd December 2016 and 1st & 2nd January 2017
  • Telescope: RCOS 12.5 inch at f/9 and Takahashi FSQ106N
  • Camera: Apogee Alta U9 and Canon 60D
  • Exposures: OIII 24 x 30 mins, Ha 14 x 20 mins and RGB (TAK) 22 x 10 mins.

Type of object: Planetary nebula

RA (J2000.0): 03h 03m 48.8s

Dec (J2000.0): +64° 53' 28"

Constellation: Cassiopeia

Magnitude: 16.0

Size: 8.3' (OIII ring approx 15' dia)

Magnitude of central star: 14 variable

astronow-iom

HFG1

HFG1



 

29th January 2017

Planetary Nebula Abell 5

 

This Planetary Nebula does exist but there is virtually no data or images of it!

I was asked if I had an image of Abell 5 by Owen Brazell, writer of Deep-sky Challenge section for Astronomy Now magazine. The answer was not yet but it was on my list for this winter. He was considering it for one of his forthcoming challenges for visual observers. However, following my my reports that is was mighty faint on my OIII exposures, he decided against setting this object as a challenge even for the big Dobsonian boys. The OIII band is the filter of choice for visual PN observers as our eyes are pretty insensitive to h-alpha.

The H-alpha does record reasonably well if not brightly but the OIII is extremely faint. I really needed 30 minute sub-exposures. The central star is brightest in the UV and is only mag. 21.4 in the visible so was out of reach for me using narrowband filters.

Image Details

  • Dates: 26th,28th & 29th November 2016
  • Telescope: RCOS 12.5 inch at f/9
  • Camera: Apogee Alta U9
  • Exposures: Ha 12 x 20 mins + OIII 12 x 20 mins

Type of object: Planetary nebula

RA (J2000.0): 02h 52m 18.0s

Dec (J2000.0): +50° 36' 00"

Constellation: Perseus

Magnitude: 16.0

Size: 2.2'x2.0'

Magnitude of central star: 21.4 (V)

Object classification: 4

Abell5

Abell 5



 

15th January 2017

Pisces Cloud Galaxy Cluster (Zwicky 0107.5+3212)

 

The Pisces Cloud actually refers to the whole cluster whereas the north-south chain of mainly elliptical galaxies is more accurately known as Arp331. The cluster is in turn part of the huge Perseus-Pisces supercluster. Current distance estimates for the Cloud place it just over 200 million light years away.

The cloud (and chain) is centred on NGC 383. There is some debate as to whether this an elliptical galaxy or an S0 type. It is also known as 3C 31 - a Fanaroff-Riley type I radio galaxy. Compared to quasars, these are (relatively) low-powered radio-galaxies with active galactic nuclei and relativistic jets (see right).

As the jets move out from the nucleus they interact with the interstellar medium producing shock fronts and eventually slowing down. The jets are fueled by material accreting onto a super-massive black hole. The high energy particles are shot into extragalactic space at speeds approaching the speed of light, where they eventually spread out into massive radio plumes extended further out than the complete chain.

Image Details

  • Dates: 24-25th November 2016
  • Telescope: RCOS 12.5 inch at f/9 and Takahashi FSQ106N
  • Camera: Apogee Alta U9 and Canon 60D
  • Exposures: Luminance 16 x 20 mins - RGB 30 x 10 mins (Tak)

Radio Galaxy
NRAO/HST images

Pices Cloud

Pisces Cloud



 

1st January 2017

Galaxy NGC 1023 (Arp 135)

 

NGC 1023 is the brightest member of the LGG 70 group (Garcia 1993) and is overlaid by its closest companion NGC 1023A. The latter is a low-luminosity patch located near the eastern (left) end of the galaxy. NGC 1023A was first recognised as an individual galaxy by Barbon & Capaccioli (1975) and classified as Magellanic irregular or late-type dwarf galaxy by Capaccioli et al.(1986). It is slightly bluer than NGC1023. NGC 1023 is classified as a barred lenticular SB0 galaxy and is located in Perseus.

Forbes et al (2014) used Hubble Space Telescope images to study "faint fuzzies" (FF) ie clusters in NGC 1023 (right). Their image also recorded 2 Ultra Compact Dwarfs (UCD) marked with magenta squares. These rare objects were originally thought to be found only in large clusters but have now been found elsewhere as is the case here. Latest thinking is they are more likely not ultra compact dwarf (galaxies) but super star clusters, 10 times the size of globular clusters. However, the jury is still out on this one. Note the Hubble image for some reason has misplaced stars. Aligning it with my image was tricky until I realised what was wrong. How they have ended up with stars in the wrong place is a puzzle.

ucd-1023Blow-up of the UCDs from my image below.

Image Details

  • Dates: 20th November 2016
  • Telescope: RCOS 12.5 inch at f/9 and Takahashi FSQ106N
  • Camera: Apogee Alta U9 and Canon 60D
  • Exposures: Luminance 12 x 20 mins - RGB 25 x 10 mins (Tak)
forbes-UCD

(Location of red and Blue FFs plus the 2 UCDs in a Hubble image of NGC 1023 - Forbes et al. 2014.

Forbes et al. didn't make a good job of their mosaic image and several stars are misplaced!

ngc1023

NGC 1023



The imageBLOG continues at Archive 2016 Click Here

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