Nocturnal Safari

March 16, 2016 by grahamrob in Deep Sky Objects, General Astronomy and tagged Canis Major, Constellations, DSO Imaging, Monoceros, Nebulae, Orion | 3 Comments

night eyes

Asterisms of the night sky have long been the basis for astronomy, navigation, astrology, myths, general stories and even religion. Whilst over millennia their shapes inevitably change, on the scale of human life there is an element of permanence and certainty. With so many stars it is not difficult to ‘join-the-dots’ in order to arrive at a recognisable shape, thereby making identification easier. Simplest amongst these are the seasonal often geometric asterisms such as the Summer Triangle, Winter Hexagon and The Plough or Big Dipper. However, it is the 88 constellations that dominate our definition and description of the night sky.

Computer based planetarium usually trace the relevant shapes and often the underlying historical figures from which they were originally derived – though frankly in some cases these can be quite spurious and even misleading. Of the total constellations: 17 depict humans or mythological figures, 29 inanimate objects and a whopping 42 animals – the night sky might literally be described as something of a zoo!

Despite my cynicism the patterns can be very helpful when initially learning the night sky, as well as for navigating and descriptive purposes. When starting out in astronomy I deliberately did not purchase a GoTo mount in order to first better master the geography of the night’s celestial sphere. For this purpose I purchased a planisphere and to a degree (no pun intended) it did initially help but with so many stars, light pollution and the odd cloud it wasn’t always easy when it came to essential star identification and alignment. I am sure I will forever benefit from the effort but this is 2016 and inevitably I have succumbed to using Google Sky on my smartphone to identify or at least confirm a star’s identity. Equally inevitable, I now use an AZ-EQ6 GoTo mount, which when linked to the Cartes du Ciel planetarium software is a quick and powerful combination for locating and tracking objects.

As previously discussed, this winter has been unusually cloudy but I recently managed a rare though decent imaging session in which I was able to capture night animals of a different sort. Probably like most astronomers I find the mid-winter night sky to be the highlight of the year, making the aforementioned seeing problems all the more frustrating. I have already imaged various parts of everyone’s favourite, the Orion constellation and so this time was looking for alternative objects in a similar region that would be suitable for the William Optics GT81. Whilst I find many if not most of the star asterisms unconvincing, there’s no denying that some of the DSO shapes really do look like animals and this time I found two.

animal2

NGC 2174 or the Monkey Head Nebula is located within the Milky Way, between Orion’s club and Castor’s left foot. An HII emission nebula, with an apparent magnitude of +6.8 and 40’ apparent dimension, it was a good target and a very convincing monkey’s head. Closer inspection of the image shows another smaller HII nebula north above NGC 2174 called Sh2-247, that is not only connected to the monkey but they are both part of the even larger GEM OB-1 molecular cloud complex which covers a massive region of 570 x 770 light-years!

NGC 2174 & Sh2-247 nebula above. WO GT81 & modded Canon 550D + FF | 20 x 180 sec @ ISO 1,600 | 10th February 2016

NGC 2174 The Monkey Head Nebula, cropped & inverted

In addition, situated between the constellations of Canis Major and Monoceros is IC 2177 the Seagull Nebula, which is also within the Milky Way but ‘flying’ lower than the Monkey Head Nebula to the left (south-east) of the Orion. More than 2.5^o from wing to wing, a number of bright star clusters are associated with this emission nebula, notable of which is the ‘bird’s head’ designated NGC 2327; IC 2177 is also known as the Parrot’s Head Nebula, which given the form of NGC 2327 I’m inclined to prefer.

IC 2177 The Seagull Nebula. WO GT81 & modded Canon 550D + FF | 20 x 180 sec @ ISO 1,600 | 10th February 2016

I’ve previously imaged a number of other animal-like DSO objects: Jellyfish Nebula, Crab Nebula, Pelican Nebula and the famous Horsehead Nebula. Unlike the constellations they generally but not always, really do resemble the form their names imply. Now adding to this list the Monkey Head and Seagull (Parrot) Nebulae it sometimes seems like a safari rather than astronomy!

Sky Animalscrop

It’s all in the stars

February 24, 2016 by grahamrob in Deep Sky Objects, General Astronomy, Imaging, Universe and tagged Auriga, DSO Imaging, Hitchhiker's Guide to the Galaxy, Milky Way, Nebulae, Star Clusters | 2 Comments

After 24-weeks I have just completed Imagining Other Earths, a Coursera MOOC presented by David Spergel, Charles A. Young Professor of Astronomy at Princeton University – soon to become Director of the new Computational Centre of Astrophysics, NY – and cannot speak too highly of the course. In my quest to better understand what I am seeing and imaging, I have participated in five astronomy courses and this is by a country mile the best; how many country miles in a parsec I wonder? There was very little not covered about astronomy in the course, including related geology and life itself but it was outstanding for three reasons:

Frequent use of easy-to-understand equations to explain and link various processes responsible for the Universe and everything in it;
It is very comprehensive, thorough and well produced, and…
David’s lecturing is just very good – easy to understand and well delivered.

For some while now the trend in my astrophotography has been increasingly directed towards seeing the big picture and by coincidence the course followed a similar scientific theme in order to Imagine Other Earths throughout the Universe; a metaphor for life itself and possibilities across the Universe.

The ultimate question starts at the beginning – where do we come from? Moby and astrophysicists seem to have the answer: we are all made of stars. How we get from that to here may be an even bigger question and like the philosophers in The Hitchhikers Guide to the Galaxy looking for the meaning of life (answer = 42!), should keep many astrophysicists gainfully employed for aeons.

In the meantime there is strong evidence that we do indeed come from stars and their evolution through the process of nucleosynthesis, which is responsible for all but a few man-made elements that we find on Earth. Through the action of nuclear fusion a star burns its way through the periodic table, first from hydrogen to helium then carbon-oxygen-magnesium-silicon and eventually iron. Thereafter the other, heavier elements require even more extreme conditions – heat & pressure – that can only be found in the late or final stage of a star’s life such as a Super Nova.

When the Periodic Table was initially formulated in 1863 by Dimitri Mendeleev there were 53 elements, which through subsequent discovery have now grown to 118. I find it wonderful and exciting that almost all of these can be attributed to stellar evolution, which can be viewed and imaged in the night sky.

At this time of the year the Milky Way is a dominant feature passing across the winter night sky which provides numerous, sometimes spectacular objects that are favourable for imaging. Located close to the western edge of the Milky Way in the constellation of Auriga about 1,500 light-years from Earth, is IC 405 or Flaming Star Nebula and nearby (visually) IC 410 or Tadpole Nebula, itself at 12,000 light-years distance. Located across the central area between these objects is a star field, notable of which and actually within the IC 405 is the O-type blue variable star of AE Aurigae, that is responsible for illuminating the nebulae.

IC 405 is formed of two sections, consisting of an emission and reflection nebula. Radiation from the variable star AE Aurigea, that is located in the lower part of upper-east (left) lobe, excites the hydrogen gas of the nebula which then glows red, while carbon-rich dust also creates a blue reflection from the same star.

IC 405 (right)-The Flaming Star Nebula inc AE Aurigae varibale star & IC 405-The Tadpole Nebula: WO GT81 & modded Canon 550D + FF | 15 x 180 sec @ ISO 1,600 & full calibration | 8th December 2015

Located within the nebula IC 410 and partly responsible for its illumination is an open cluster of massive young stars, NGC 1893. Being just 4-million years old these bright star clusters are the site of new star formation and therefore are just starting their creation of new elements. The so named ‘tadpoles’ are filaments of cool gas and dust about 10 light-years long.

IC 410-The Tadpole Nebula: Illuminated from within by the NGC 1839 star cluster. Image cropped and forced to highlight the two ‘tadpoles’, which can just be seen indicated in the green ellipses (‘tails’ upwards)

Each nebula is large, respectively 30’ x 20’ and 40’ x 30’, with an apparent magnitude of +6.0, which combined with the star AE Aurigae makes an excellent target for the William Optics GT81. I find it thrilling to consider the processes taking place in these objects that I have captured in the photograph, which surely represents the ultimate Big Picture?

Good Vibrations

February 7, 2016 by grahamrob in Deep Sky Objects, Imaging and tagged DSO Imaging, Nebulae, Perseus | 1 Comment

Ever since autumn undertaking astronomy has continued to be very difficult at Fairvale Observatory; except for some periods coincident with the full Moon, I can count on the fingers of one hand the times we’ve had clear dark skies – at this rate I’m going to need a new hobby! As a result 8^th December was the last time the observatory was in action – frustrating but what can I do? Notwithstanding, on that occasion I was able to obtain decent images of three different objects, two of which were new for me.

I live under the grey bit in the South East i.e. cloudy

Apart from persistent cloud, the winter has also been unusually wet and in general I yearn for better weather. In the absence of more desirable conditions I was at least able to image something that kind of reminds us of a better more pleasant climate, NGC 1499 or The California Nebula – so called because being like the shape state of California.

perseus

Located in the constellation of Perseus, within the Orion arm of the Milky Way some 1,500 light-years from Earth, NGC 1499 is a large emission nebula about 100 light-years long, or nearly 4^o. The HII nebula is ionized by the nearby but otherwise unrelated star of Xi Persei (Menkib) but despite its size it is difficult to view and can only be properly appreciated using long exposure imaging, preferably with an Hβ filter (486 Nm) or in my case a modded-DSLR camera and light pollution filter (450 Nm – 550 Nm & 650 – 750 Nm) worked quite well.

NGC 1499 California Nebula – Xi Persei (Menkib @ top), North down: Wo GT81 & modded Canon 550D + FF | 16 x 180 secs @ ISO 1,600 & full calibration | 8th December 2016

It was a pleasure to finally image the California Nebula, which is an ideal object for the William Optics GT81. However, being nearly 2-months since imaging NGC 1499 it is now only present during the early evening and will soon be gone from the sky altogether for another year, pointing the way towards the Spring Equinox in a few weeks and hopefully improved weather and astronomy conditions, in every sense leading to good vibrations!

A Wider Perspective

January 23, 2016 by grahamrob in Deep Sky Objects, Equipment, General Astronomy, Widefield Imaging and tagged DSO Imaging, Nebulae, Orion, Photography | 3 Comments

I like to think and operate at both ends of the spectrum: sometimes considering detail and its implications and often exquisite beauty, whilst on the other hand taking a wider view will often provide broader insight and answers – notwithstanding, I am usually drawn towards the latter. There was no shortage of scope for such thoughts in my career as a geologist and now as my hobby in astronomy. I have become fascinated with parts of the Universe and captivated by imaging them: galaxies, nebulae, star cluster etc. but the wider view is often even more astounding and perplexing.

you-are-here-2

My nascent astroimaging has already produced some rewarding photographs, which using the fast William Optics GT81 refractor has enabled me to obtain images of up to 3^o FOV. In fact this became something of a theme last year, successfully imaging features such as the Sadr Region and as they say, one thing has led to another. Wanting to image even wider views there’s mostly only one alternative, using a camera and lens. I’ve tried this before, on a tripod and fixed to the ALT-AZ EQ6 mount but with mixed success. Meanwhile, I came across excellent pictures taken using lightweight tracking mounts on a tripod and as a result the way forwards became obvious; after scanning the Classified advertisements online for a while I was fortunate to find and purchase a second-hand Vixen Polarie mount last September.

Probably my favourite object, which can rightly be considered the signature image of the winter night sky and is therefore around at the moment, is the constellation of Orion and especially its numerous and often exciting constituent parts: M42, Horsehead & Flame Nebulae etc. After waiting for weeks for the clouds to clear, I briefly got a chance to image Orion using the Vixen Polarie early in November, whilst at the same time using the WO GT81 to obtain yet another picture of the irresistible Great Orion Nebula M42.

Orion’s Sword – including the wonderful Great Orion Nebula M42 et al : WO GT81 + modded Canon 550D & FF | 14 x 180 secs @ ISO 1,600 | 9th November 2015

The Vixen Polarie is a deceivingly simple and well-made solution to obtaining long exposure images of the wider night sky using a camera and lens. As stability remains essential for the mount and camera to operate at their best, I also purchased a decent Manfrotto tripod and suitable ball heads to attach the Polarie. After that it was simple, well not quite! Trying out the Polarie at the same time as using the GT81 and being first time out was a mistake. I fumbled setting up the equipment and initially even forgot to turn on the tracking, leaving only a short time to grab a few images before the clouds rolled in once again! Not surprisingly the results were mixed and I was left frustrated. With continuing poor seeing conditions, it was to be a further month before I had an opportunity to properly use the Vixen Polarie again – this time with a new Sigma 10 – 20 mm ultra-wide angle lens I had just purchased.

Vixen Polarie & Canon 700D + 18 – 55mm lens | 19 x 60 secs @ ISO 800 | 9th November 2015

Having by now spent more time looking at the manual (we all get there, in the end) and concentrating on imaging using only the Polarie, this time I was able to achieve a good set-up and remembered the correct sequence of operation. As the mount sits high on the tripod I am just about able to see Polaris in a small gap between the roof of my garage and house, something hitherto impossible when using the lower positioned AZ-EQ6 mount. As a result I am able to achieve a reasonably good visual polar alignment, though a polar scope made specifically for the Vixen Polarie would improve this further; probably something for another time? Nevertheless, such an alignment at Fairvale Observatory is a first and was a major breakthrough that has already permitted exposures of 4 minutes and could probably go to 5 to 6 minutes or more.

The high position of the Vixen Polarie on the tripod provides an otherwise elusive view of Polaris between the garage / utility room and the main house for polar alignment, at last! Alignment of the mount is carried out by viewing through the hole in the top right of the Polarie – better alignment can be achieved by using a polar scope which fits through the middle of the Polarie mount.

Once polar aligned, fixed on the front of the Vixen Polarie the camera then rotates to follow the celestial sphere and chosen object in order to achieve a sharp image with long exposures. For this purpose there are 4 tracking rates: sidereal, half sidereal, lunar and solar. With no interesting foreground here I concentrated on the sky by using the sidereal rate; for more scenic shots with the landscape incorporated, using half-sidereal provides a compromise in order to achieve a non-blurred image of the sky and landscape, though this method is inevitably limited to shorter exposures than sidereal.

Vixen Polarie mount on Manfrotto tripod – a lightweight, portable tracking method for widefield astroimaging

Vixen Polarie – close-up showing x2 ball head fittings

Vixen Polarie – tracking speed settings

VP Dial

Vixen Polarie with DSLR attached & ultra-wide lens

I have adapted a somewhat basic red dot finder to fit on top of the DSLR camera using the hot shoe, which was immediately helpful to accurately locate the desired target area. However, as previously experienced, once again achieving focus proved quite difficult, basically requiring just trial and error; I intend to look into a more efficient method but in the absence of a Bahtinov mask this is likely to be the best technique for now. A laptop can be used for image capture but maintaining the themes of portability and simplicity, I successfully used an intervalometer to control exposures.

Whilst initially my target was the Orion constellation, I’ve long held the ambition to image Barnard’s Loop, a much larger and elusive feature surrounding the constellation and more difficult to photograph. I had tried this before last January with limited success but ever since acquiring the Vixen Polarie this has been my No1 imaging goal.

Orion Constellation 220115 Stacked1L2C3GX (Large)

The Orion Constellation & Barnard’s Loop (up / north is left) : AZ-EQ6 Mount + Canon 550D & 200mm Telephoto | 180 secs @ ISO 1,600 & calibration | 22nd January 2015

Unable to see with the naked eye, only using long exposure photography unveils the majesty of Barnard’s Loop, an emission nebula to the left (east) of the Orion constellation. Shaped as a large-C, the loop completely encompasses the eastern side of the constellation and is thought to be a recent supernova front moving out from Orion and illuminated by stars from within the nebula, as well as part of the Orion Molecular Cloud Complex. Discovered and named after astrophotographer E. E. Barnard in 1895, at some 14^o or 300 million light-years across Barnard’s Loop is enormous; however, the entire Molecular Cloud is about 30^o in size!

pleyades31_02

The Orion constellation was originally conceived in Greek mythology as the Hunter, pursuing Taurus the Bull to the west, with the stars tracing out a shape of a hunter holding a shield and club in each hand, a belt around the waste with a sword attached. What they could not have known at the time is that he also has a head, in the form of the Lamda Orionis Nebula (Sh2-264), located centrally and above Betelgeuse and Bellatrix.

Barnard’s Loop & Lamda Orionis Nebula : Vixen Polarie & modded Canon 550D + Sigma UWA @ 20mm | 11 x 240 secs @ ISO 1,600 + darks | 7th January 2016

I was able to image Barnard’s Loop on 7^th and 14^th January; at ISO 1,600 the first images showed the Loop but certainly left room for improvement, as a result I shot the subsequent images at ISO 800 and obtained a noticeably better outcome – though I had to push post processing to reveal the features. The Loop and head are clearly evident but I’ve been intrigued to see other objects also revealed, albeit without the detail obtained with prime focus imaging using the telescope: Great Orion Nebula, Horses Head & Flame Nebulae and surprisingly on the left (east) of the Loop the Rosette Nebula. Looking at other’s images of Barnard’s Loop it is clear that I will need to take significantly more subs to properly reveal the full beauty of this wonderful and very large feature – dark skies would be nice too – but for the moment I am pleased with my first outing using the Vixen Polarie, which holds great promise for capturing a wider perspective of the Universe.

Barnard’s Loop & Lamda Orionis Nebula + Rosette Nebula on far left : Vixen Polarie & modded Canon 550D + Sigma UWA lens @ 20mm | 14 x 240 secs @ ISO 800 | 14th January 2016

Reflections – 2015

January 1, 2016 by grahamrob in Deep Sky Objects, Equipment, Imaging, Software, Solar system, Widefield Imaging and tagged Andromeda, DSO Imaging, Galaxies, Lunar Eclipse, Orion, Photography, Solar system | 1 Comment

Launched in August 2014, 2015 is the first full year of Watch This Space (Man) and despite some personal set-backs it’s been an interesting year astronomically, with much to write about. Whilst I have made progress with my imaging, it was not what I would have wished for but nonetheless I have been pleased with the outcome. Continuing on from last year, Reflections is a recap and thoughts on all that happened to me astronomically in 2015 and looks forward to the coming year.

Although this website is just intended as my record of A personal discovery of the Universe through astronomy and astrophotography, it has been pleasing to see that over the year the site has attracted 1,310 visitors from 77 countries around the world and over 2,700 views; you are all most welcome. This was not the intention of the blog but I am humbled by the interest and would be very pleased to hear from anyone who would like to get in touch with queries, comments or just to say hello – contact details are in the About section.

JANUARY TO MARCH

The first quarter turned out to be my most active and successful period of the year for reasons that will become apparent later. Strictly speaking my image of the Rosette Nebula posted on 5^th January was taken on 29^th December 2014 but what an image to start the year with, clearly I was doing something right by now. Notwithstanding, from looking at pictures of the same object taken by other more accomplished photographers, it was evident that something was missing – red! This was an easy to problem to solve and I immediately set out on a quest to find a suitably modified camera with the IR filter removed. Soon thereafter I was lucky to find an excellent second hand modded Canon EOS 550D, which has now become my main imaging camera of choice and with all that extra red Ha-light has led to a quantum improvement of many images since. Such cameras are very popular so I felt lucky to have secured this one.

Orion’s Sword: M42 The Great Orion Nebula, Running Man Nebula & NGC 1981 Star Cluster
WO GT81 + modded Canon 550D & FF | 10 x 180 secs @ ISO 800 & darks calibration | 8th February 2015. Modification of the camera by removing the IR filter increased red Ha-light.

EQMOD / ASCOM is a popular free software project developed by amateurs that, amongst other things, provides computer and planetarium linked control of the mount; with other compatible linked programmes such as APT (Astrophotography Tool) and PHD (Push Here Dummy) control can be extended to cameras and for autoguiding. At the start of the year I successfully started using Carte du Ciel planetarium linked with EQMOD for computer controlled alignment and mount control, which as expected was very useful – particularly when it got really cold and I was able to take the equipment indoors and operate the equipment remotely. However, later in the year I have encountered connection problems which are, as yet, not fully resolved.

Whilst EQMOD is an excellent project which provides first class mount control when working, it requires additional faffing about and problems on a different level of scale, which with limited imaging conditions in the UK and having to set up outside from scratch each time is a pain. For this reason and others I have not yet moved to autoguiding, which I know will be highly beneficial to imaging but for the moment has proved to be a step too far for me. Such is the fickle nature of all this that I’m now considering other ways of achieving the same end, perhaps with professional software control and a stand-alone guider, such as the Lacerta M-GEN – of course a dedicated observatory would help a lot but seems unlikely at the moment!

I have previously found the early winter sky of Orion, Taurus, Pegasus and Monoceros very productive with beautiful imaging objects such as M42 and the Horsehead Nebula. However, this year looking more closely at the late-winter / early spring skies turned out to be just as exciting, with a veritable playground of galaxies to choose from during February and March. Notwithstanding, the highlight during the winter was successfully imaging Comet Lovejoy, a first for me that required changes to normal DSO and planetary imaging techniques as this ephemeral object was speeding across the night sky at over 70,000 mph – post processing also turned out to be quite different.

C/2014 Q2 Comet Lovejoy
WO GT81 + Canon 550D (modded) & FF | 40 x 20secs @ ISO1,600 + darks | 16th January 2014

No	Date	Object*	Name
1	16/01/15	C/2014 Q2	Comet Lovejoy
2	16/01/15	C/2014 Q2	Comet Lovejoy
3	16/01/15	NGC 2244	Rosette Nebula
4	22/01/15	M42 etc	Orion Nebula
5	22/01/15	M45	Pleiades
6	22/01/15		Comet Lovejoy
7	22/01/15		Comet Lovejoy
8	22/01/15		Banard’s Loop
9	22/01/15		Banard’s Loop
10	22/01/15		Orion Constellation
11	24/01/15	NGC 1909	Witch Head Nebula
12	24/01/15	NGC 2392	Eskimo Nebula
13	24/01/15	M44	Beehive Cluster
14	24/01/15	IC-443	Jellyfish Nebula
15	08/02/15	M42	Gt Orion Nebula etc
16	08/02/15	Barnard 33	Horsehead Nebula etc
17	21/02/15	M65	Leo Triplet (Galaxies)
18	21/02/15	M105	M96 Group (Galaxies)
19	24/02/15		Venus & Mars
20	25/03/15	NGC 2903	Spiral galaxy – Leo
21	25/03/15	NGC 3842	Galaxy cluster: Leo
22	25/03/15	M 88	Spiral galaxy: Virgo cluster
23	25/03/15	M100	Spiral galaxy: Virgo cluster
24	26/03/15	NGC 4438	Markarian’s Chain
25	26/03/15	M104	Sombrero
26	26/03/15	M53	Globular cluster

*Record of quarterly photographic images in 2015, excluding other widefield pictures

APRIL TO JUNE

Things took a turn for the worse in April when I went into hospital for a knee replacement operation. All went well but it is a major operation and recovery has been slow and often painful, thus prohibiting any real astronomy until September. It did however provide the time and opportunity to read about astronomy and pursue some MOOC astronomy courses.

After a period of convalescence, I did manage to obtain some widefield camera shots of the planets, the ISS and simple night sky images in the summer. Whilst not as satisfying as prime focus photography, it was interesting and kept me sane during this otherwise difficult time.

1st July 2015. Bingo = conjunction; though one day later Jupiter has now moved to the right of Venus.

1st July 2015. Conjunction of Jupiter to the right of Venus.

No	Date	Object	Name
27	11/04/15	NGC 4438	Markarian’s Chain
28	11/04/15	NGC 4565	Spiral galaxy-side

JUNE TO SEPTEMBER

This period was more of the same until on 19^th September, when at last I managed to set-up Fairvale Observatory for the first time since March, what a relief. As a bonus I was particularly chuffed to achieve a good image of the Andromeda Galaxy but the highlight of this period and the year was the lunar eclipse at the end of the month on 28^th September.

For once everything was perfect: a clear sky all night with a perfect view of the eclipse from start to finish. I stayed up all night and would have to say it was one of the best, if not the best event I have so far experienced since taking up astronomy; apart from being an outstanding imaging opportunity, the ambiance throughout the eclipse was spellbinding. I was therefore very pleased to obtain an excellent set of images of the entire eclipse, mainly using a prime focus camera set-up with the WO GT81 telescope but also with an alternative camera and telephoto lens on a tripod. The memory of that night will stay with me for a long while and, in part, helped to make up for the lost time since my operation in April.

Eclipse Animation 28th September 2015

No	Date	Object	Name
29	19/09/15	IC 5070	Pelican Nebula
30	19/09/15	NGC 6979	Pickering inc Veil Nebula
31	19/09/15	M15	Globular Cluster
32	19/09/15	M31	Andromeda
33	28/09/15	Lunar Eclipse	Entry @ 1 sec intervals
	28/09/15	Lunar Eclipse	Totality
	28/09/15	Lunar Eclipse	Entry @ 1 sec intervals
34	28/09/15	Lunar Eclipse	Exit – camera + tripod
35	30/09/15	IC 1318	Sadr Region (+NGC 6910)
36	30/09/15	IC 1318	Sadr Region – Pt2

OCTOBER TO DECEMBER

The final quarter of the year has been very frustrating due to the almost complete absence of suitable imaging conditions, mainly due to cloud cover but even when there was a few clear nights it was of course a full Moon – you can’t win! I was particularly unhappy as this time marks the arrival of the constellation Orion and all its wonderful imaging opportunities, for which I had new plans.

Given the short focal length of the William Optics GT81 and relatively small aperture, used with a APS-C cropped sensor DSLR camera the resulting field-of-view is a quite large and, where possible, this year I’ve therefore concentrated on objects of 2.5^o to 3.0^o apparent dimensions. Together with the modded camera this has resulted in some exciting new images of old and new objects.

However, large as the field-of-view is with this set-up, I have become increasingly aware of the simply enormous scale of some nebulous features such as Barnard’s Loop. As a result I have become more interested in widefield imaging using just a camera and tripod. Like prime focus imaging, widefield imaging will also benefit from achieving longer exposures through the use of tracking. Early in this period I was fortunate to purchase a Vixen Polarie lightweight tracking mount for this purpose, but due to the aforementioned conditions I have unfortunately been unable to use it very much. In fact it’s fair to say that other than some brief experimentation, it’s hardly been used at all so far. Notwithstanding, I can see the potential and have high hopes for future imaging opportunities when the clouds part and the Moon is absent.

The year finished with a couple of other purchases that I hope will assist with imaging in 2016:

A new laptop – running Windows 10 with a core i7 Intel chip, 2 TB hard drive, 16 GB RAM, dedicated AMD graphics card and an HD 17.3” screen, which I hope will help improve post processing. Running my preferred Windows 7 operating system, I will continue to use the smaller 13” i5 chip laptop for mount and camera control.

Ultra-Wide Angle lens – the truth is I’ve recently acquired this wonderful Sigma 10 – 22mm f3.5 lens for a trip to the Grand Canyon in April, however, I will of course also be using it with the Vixen Polarie when the skies clear.

No	Date	Object	Name
37	09/10/15	NGC 6888	Crescent Nebula
38	09/10/15	M 74	Spiral galaxy (near Pegasus)
39	09/10/15	NGC 7814	Little Sombrero
40	09/10/15	NGC 7479	Barred spiral galaxy
41	09/10/15	M 31	Andromeda galaxy
42	08/12/15	NGC 1499	California Nebula
43	08/12/15	IC 405	Flaming Star Nebula
44	08/12/15	NGC 2264	Cone Nebula
45	09/12/15	M42	Great Orion Nebula etc
46	08/12/15	Orion	Constellation

Favourite Images

Despite the lack of activity this year I have been fortunate to obtain some good images and I can only hope 2016 will be just as rewarding. Acting as judge and jury, my personal favourites in no particular order are:

NGC 2024 Flame Nebula & Horsehead Nebula
WO GT81 + modded Canon 550D & FF | 10 x 180 secs @ ISO 800 & darks calibration | 8th February 2015

Eclipse: Inward sequence from umbral contact to totality
WO GT81 + Canon 700D + FF | 1/500 to 1/3 sec @ ISO 100 | 18th September 2015

M31 Andromeda Galaxy
WO GT 81 + modded Canon 550D + FF | 9 x 120 secs @ ISO 1,600 | 19th September 2015

Goals for 2016

After the year that’s just finished I am reluctant to set out goals for 2016 but here goes:

Increase imaging exposure times: This is a euphemism for (a) improving equipment set-up and alignment, and (b) start autoguiding. As previously outlined, I have been struggling with both of these issues but one way or another I have to overcome the problems in order to obtain exposure times of at least 5-minutes and hopefully longer;

Improve processing: I was pleased to get to grips with Photoshop in 2015, albeit using a very old version, which together with other minor improvements to processing has added to the quality of the final images. However, I know that even now there is more to be teased out of the existing imaging data for which I am already considering new software;

Start widefield imaging: First I just need clear skies in order to get out and start using the Vixen Polarie tracking mount from Fairvale Observatory, with the initial objective of imaging Barnard’s Loop, which has hitherto proved elusive to my current set-up. However, one of the attractions of the Polarie-DSLR-Tripod combination is its portability, which I’d like to put to good use in 2016 by visiting dark sky areas in the UK.

There are other possible developments which at the moment seem unlikely to eventuate but you never know: a larger probably SCT telescope, a cooled CCD camera, and / or a permanent observatory (well I can dream can’t I?).

So all things considered 2015 was a good but not great year. As a fundamental and important development I had really hoped to start autoguiding and thus increase exposure times but it was not to be. Certainly the loss of astronomy time between April and September was a major set-back in many different ways. Notwithstanding, during the remaining times available when I did manage to get outside I believe I achieved some of my best images to date and discovered many new and exciting objects in the night sky, which can’t be bad. In particular, I am sure the lunar eclipse in September will remain a highlight of my astronomy experiences for many years to come.

Harvest Moon at Totality
WO + Canon 700D + FF | 1/3rd Sec @ ISO 400 | 28th September 2015

I’m now looking forwards to 12-months of uninterrupted astronomy, clear skies and plenty to report in the WTSM blog at the end of 2016!

Watch this space!

Spaceship Earth

December 23, 2015 by grahamrob in Deep Sky Objects, Earth, General Astronomy, Software and tagged DSO Imaging, Earth, Monoceros, Orion, Solar system | Leave a comment

I’m now into my second year of ‘serious’ astronomy and astrophotography, which accompanied by a greater knowledge of the Universe has brought an element of familiarity: with the equipment, with viewing & imaging techniques and space itself. In the past I have worked underground as a geologist on mines and like to think that I have good spatial awareness. Through this growing familiarity and knowledge of the night sky, I have become increasingly aware of our place in the Universe and how we on Earth are travelling through space; I also feel a growing empathy other peoples such as mariners who use and relate to the sky and space in a way ordinary people do not.

Whilst spinning on its axis at 1,037 mph at the equator (653 mph here at Fairvale Observatory’s higher latitude), the Earth is moving at about 70,000 mph round the Sun. Furthermore, located in the Orion-Cygnus arm of the Milky Way, the Solar System is also moving around the spiral galaxy at 500,000 mph, resulting in a galactic year of nearly 250,000 Earth years . Notwithstanding these complex and frankly mind boggling statistics, it thankfully all feels quite serene when outside at night with my telescope at Fairvale Observatory.

Going back some 5,000 years the constellations might seem to describe the ‘shape’ of space and provide a sense of stability to the sky but this is misleading. These and other asterisms are 2D patterns that mankind has created for practical use, whereas in reality most of the stars that make up these patterns bear little if any meaningful relationship with each other when viewed in 3D – like this animation showing the true shape of Orion.

Furthermore, under the force of gravity and other as yet unknown influences e.g. dark energy, these too are moving through space in their own way at vast speeds. In reality the constellations are therefore anything but permanent and through the millennia their apparent shapes change and will eventually be destroyed as far as we on Earth are concerned. As with my professional subject geology, this is the problem with space – it is very big and the timescales are very, very large, essentially beyond human comprehension, which result in otherwise unimaginable events; this animation wonderfully illustrates the scale and complexity of the known Universe.

Space selfie = the insignificance of Earth.
The Pale Blue Spot photograph of Earth (right side of picture) taken 6 billion kilometers (40.5 AU) away by Voyager-1 on February 14th 1990,

The beauty of such a system is that it can be modelled very accurately, from which it is possible to predict with great certainty the projected position of all these celestial objects, thus making spaceflight and the prediction of astronomical events possible. Likewise using the same data modelling it is possible to look backwards at past events. Such computerisation is no longer just the preserve of NASA and University academics but is at our fingertips using a computer based planetarium, in my case Carte du Ciel – incredible!

Given the time of year I have therefore used the aforesaid programme to generate a view of the night sky from Bethlehem 2015 years ago on the morning and evening of 25^th December. Even then differences can be seen in the shape of the constellations compared to now. If we are to believe the story of the Three Wise Men following a bight ‘star’ at this time, it seems it would be most likely to be in the morning when first Jupiter and then Venus are present. Either way it’s fascinating to be able to model the night sky in this way for any chosen moment in time.

Santa's view of Bethlehem - actually from the ISS on 24th December 2011

Santa’s view of Bethlehem from the ISS on 24th December 2011

After weeks of cloud cover I recently managed to get outside again for what turned out to be a wonderfully clear night, from dawn to dusk, furthermore there was no Moon! As a result imaging was productive and included some exciting new objects. However, again given the time of year for the moment I am repeating an object used last Christmas. One year on the difference is that this time I have used a modded Canon 550D DSLR camera and thus improved (I think) the red Ha-light detail.

Cone Nebula & Christmas Tree Cluster WO GT81 + Modded Canon 550D & FF | 15 sec @ ISO 1,600 + calibration | 8th December 2015

Cone Nebula & Christmas Tree Cluster – right of centre
WO GT81 + Modded Canon 550D & FF | 15 sec @ ISO 1,600 + calibration | 8th December 2015

Cone Nebula (bottom centre) & Christmas Tree Cluster (inverted)

NGC 2264 or Christmas Tree cluster and its neighbour the Cone Nebula are located within the Monoceros AKA Unicorn constellation, which being part of the Milky Way are therefore inextricably linked to a similar destiny as spaceship Earth as it makes its way through space. Being some 2,700 light-years away we are unlikely to meet, though you never know with space and time!

HAPPY CHRISTMAS

It’s all relative

December 5, 2015 by grahamrob in Deep Sky Objects and tagged DSO Imaging, Globular Clusters, Pegasus | 2 Comments

Having missed 6-months astronomy earlier this year following an operation, come September I was desperate to get back to my nascent interest in astronomy and astroimaging. Apart from some initial operating mishaps, it turned out to be a good month: warm evenings, clear skies and interesting skies. Since then it’s all gone Pete Tong, with no imaging opportunities here at Fairvale Observatory since early October due either to cloudy skies or the coincidence of the full Moon with clear periods; it was therefore not surprising to learn that November was recorded as the dullest on record, with just 18 hours of sunshine compared to an average of 63 hours.

My antidote to physical incapacity and cloudy skies this year has been the MOOC or Massive Open Online Course – free online courses run by Universities from all over the world, in my case of course I naturally chose various aspects of astronomy:

In the night sky: Orion – Monica Grady, Open University. Orion constellation and star evolution.
Moons – David Rothery, Open University. Everything about moons; there are 176 moons in the Solar System some bigger than planets and some with the potential for life.
AstroTech: The science and technology behind astronomical discovery – Andy Lawrence & Catherine Hymans, Edinburgh University. Does what it says on the tin!
Imagining Other Earths – David Spergel, Princeton University. The complete astronomy course and more! Ongoing 24-week course that covers just about everything in astronomy – outstanding.
Gravity! – Pierre Binétruy and George Smoot (Nobel Laureate), Paris Centre for Cosmological Physics – Paris University Diderot. Gravity and how it shapes the universe etc.

This week marked the centenary of Einstein’s general theory of relativity and the end of the course Gravity! At the same time on Thursday ESA launched the LISAPathfinder space mission, that is designed to assess the viability of ground breaking technology which if successful will be used later to study and measure gravitational waves; whilst on this theme I also watched the movie Interstellar.

Whatever gravity is, and it is clear that despite Einstein et al we still don’t really know (no shortage of theories though), its effects clearly shape the Universe in a major way and at all levels.

One such feature is the globular cluster, groups of up to one million very old stars, tightly bound by gravity that orbit a galactic core; over 150 have so far been identified with the Milky Way Galaxy. I find them to be one of the most interesting and enigmatic features of astronomy and therefore before the clouds rolled in some weeks ago I managed to image such a cluster, M15.

Globular star cluster M15 lies about 33,000 light years away towards the constellation Pegasus, about 4° northwest of Enif, the star at the tip of Pegasus’ nose. It was discovered by French-Italian astronomer Giacomo Filippo Maraldi in 1746 and rediscovered by Messier in 1764. At magnitude +6.2, M15 is generally considered to rank amongst the finest objects of its type in the northern sky.

M15 Globular Cluster
WO GT81 + modded Canon 550D & FF | 15 x 120 secs @ ISO 1,600 | 19th September 2015

M15 has a diameter of 120 light years and revolves around the Galaxy once every 250 million years in a prograde orbit, meaning it moves about the galaxy in the same direction as the galaxy’s own rotation. In 1974, M15 was discovered to be a source of x-ray energy, which may suggest that one or more supernova remnants are buried deep within the cluster.

With such unreliable viewing conditions in the UK it’s essential to find other areas of interest when pursuing astronomy. I have found MOOCs to be an excellent and accessible source of first rate, up-to-date information that have expanded my knowledge of astronomy significantly, whilst post processing and planning are also both essential tasks that can also often be interesting. Notwithstanding, with Orion and other exciting features of the winter sky now upon us, I can’t wait to get back outside soon.

The big picture unveiled

November 12, 2015 by grahamrob in AstroBin, Deep Sky Objects, Equipment, Imaging, Widefield Imaging and tagged Cygnus, NGC, Photography | 1 Comment

About this time last year I successfully imaged first NGC 6960 the Western Veil, AKA the Witch’s Broom Nebula and shortly afterwards NGC 6992 the Eastern Veil, which includes NGC 6995 AKA the Bat Nebula. In themselves they are both wonderful parts of the larger but perhaps more elusive (photographically speaking) Veil Nebula. Located in the constellation Cygnus, the Veil Nebula or Cygnus Loop is formed from the remains of a supernova that exploded in our galaxy about ten thousand years ago and at a distance of almost 1,500 light-years, now spans a 3^o area of the sky or 80 light-years in diameter. At the time I struggled to get these images but was very pleased with the outcome.

One year on and I was now thinking about other parts of the Veil, in particular Pickering’s Triangle. The Triangle might be thought of as the third central section of the Veil, situated between the Eastern and Western Veils but slightly further north. At some 52 x 35 arcminutes it is itself a significant feature, which surprisingly does not have an NGC catalogue number of its own.

Pickering’s Triangle

Notwithstanding the success of Pickering’s Triangle, in the end I got much more than I bargained for. This time using a modded camera, I was able to capture the entire Veil Nebula in one photograph – progress indeed.

The Veil Nebula AKA Cygnus Loop: Ultraviolet view ref. NASA

Light from the bulk of the Veil Nebula is very faint and notoriously difficult to image, whilst furthermore much of it is Ha in nature – hence this time finding its way to the camera’s sensor having had the IR filter removed. The result is a staggering view of the entire supernova, with the Witch’s Broom in the west (right), the Eastern Veil (left) and Pickering’s Triangle nestled in between. However, in addition extensive regions of delicate, wispy nebulous filaments can be seen flowing everywhere in between – hence the name of Veil.

Veil Nebula / Cygnus Loop WO GT81 & modded Canon 550D + FF | 30 x 180 sec exposures @ ISO 1,600 | 19th September 2015

Veil Nebula / Cygnus Loop
WO GT81 & modded Canon 550D + FF | 30 x 120 sec @ ISO 1,600 | 19th September 2015

Whilst I am very pleased with the resulting photograph, there’s still more to achieve another time. Apart for the added potential that would be gained from longer, guided exposures, the use of Ha and OIII filters would also uncover even more of the Veil’s diaphanous beauty.

At the limit

October 30, 2015 by grahamrob in Deep Sky Objects, Equipment, Imaging and tagged Galaxies, Pegasus, Photography | Leave a comment

Earlier this month the weather and clear skies produced particularly good imaging conditions that resulted in some excellent pictures; it’s already a distant memory as the weather has since turned cold and cloudy day-after-day – or at least every night except when there’s a full Moon! With these images knowingly in the bag and the telescope well aligned, I took the opportunity to indulge in a short session imaging some galaxies that happened to be around the Meridian at this time which, as it turned out, were located in proximity to the constellation of Pegasus.

Two of the objects (M74 & NGC 7814) were confined to just ten shots and the third fifteen, all at 180 seconds exposure and ISO 1,600. For such dim and distant objects this in itself was obviously insufficient but still it was fun to experiment. As expected the resulting images are feint and noisy but the object’s form can be clearly seen and, in the case NGC 7814 – the Little Sombrero, even the edge-on dust lanes are evident.

In order to better understand the limits of the equipment, a comparison of the images with the objects’ physical information given side-by-side illustrates the problems and possibilities for the future. The truth is that these are all at or beyond the realistic limit of my current set-up but I was interested to see what results could be achieved and I always enjoy their beauty, even if imperfectly captured.

Apart from the obvious problem of size, mainly a function of distance in this case, their apparent magnitude is also challenging. It is interesting to consider that using the 18 megapixel Canon 550D and WO GT81, each camera pixel which measures 4.30μm samples just 1.855 arc seconds per pixel and therefore even the largest of these objects (M74) spans an area of just about one tenth of a degree (0.10^o). Better alignment and longer exposure should tease out more detail but as the recorded image of each object is no more than 2% of the total image the reality is that I am pushing my luck.

Still it is fun and I have managed to capture a few of the photons that left these galaxies so long ago. As my equipment, techniques and knowledge continue to improve then hopefully so will the limits. Watch this space!

Rock On!

October 19, 2015 by grahamrob in Deep Sky Objects, Equipment, Imaging, Widefield Imaging and tagged Andromeda, Cygnus, DSO Imaging, Nebulae, Photography, Star Clusters | 2 Comments

Due to my viewing limitations at Fairvale Observatory planning is essential, with the best imaging range mainly restricted to a zone between 65^o and 85^o and within +/-20^o of the Meridian. Furthermore, as I am mostly using the William Optics GT81 telescope at the moment, imaging targets should preferably be large – something between 1^o& 2^o is perfect, such as the Rosetta Nebula at 1.3^o or Andromeda Galaxy at 190’ x 60’. As luck would have it these conditions are favourable for a number of objects at the moment and I have been somewhat spoilt for choice: North America Nebula, Veil Nebula and Andromeda.

Notwithstanding, for some reason I have until now overlooked the Sadr Region IC 1318, which is also large and in a similar part of the sky as the aforementioned North America and Veil Nebulae but perhaps overshadowed by their notoriety. In reality it is an enormous area of nebulosity containing many features worthy of imaging which are perfect at this time of the year from my location.

Sadr Region: green rectangle indicates the approximate area of IC 1318 image, yellow rectangle the NGC 6888 Crescent Nebula image.

IC 1318 is a diffuse emission nebula surrounding the star Sadr or Gamma Cygni, which is at the centre of the Cygnus Cross and on the plane of the Milky Way. The Sadr region is located deep within the Orion arm of the Milky Way about 3,000 light-years from Earth, with Gamma Cygni actually situated closer in the foreground. Such is the size of IC 1318 that its three constituent parts, A – B – C, extend over some 200 light-years or about 4 degrees, which is well beyond the FOV of the WO GT81; how could I have overlooked his enormous area of nebulosity before? As a result of its size and complexity I also chose to image two other interesting features nearby.

IC 1318 Sadr Region – image inverted & annotated

IC 1318 Sadr Region
WO GT81 + modded Canon 550D & FF | 30 x 120 secs @ ISO 1,600 | 30th September 2015

Situated just above Sadr is the small star cluster of NGC 6910 AKA Rocking Horse Cluster. Although only 10’ in size the cluster is visually quite prominent, though I struggle to see the little horse that others have identified. Notwithstanding, it is an interesting and attractive part of the Sadr region.

NGC 6910 The Rocking Horse Nebula as recorded by StarObersever.eu – located just above Gamma Cygni in the previous image.

Located about 2 degrees south west of Sadr is the Crescent Nebula NGC 6888, which is not unlike the Jellyfish Nebula in appearance but is younger in its evolution. An emission nebula, NGC 6888 is formed by a stellar wind from the Wolf-Rayet star WR 126 colliding with a slower moving wind ejected when the star previously became a red giant. The result is an illuminated shell-like feature consisting of two shock waves, one moving inward and the other outward, producing this amazing spectacle which measures some 25 light-years across. Near the end of its existence, the star will eventually end its life in a spectacular supernova explosion – now that would be an image.

NGC 6888 Crescent Nebula
WO GT81 + modded Canon 550D & FF | 20 x 180 secs @ ISO 1,600 | 9th October 2015

Crescent Nebula – cropped

Crescent Nebula – GradientXTerminator applied

Whilst IC 1318 has proved to be an excellent and productive imaging target for my equipment, it has become clear that it represents a much, much larger area of nebulosity that incorporates or is at least immediately adjacent to NGC 7000, the North America Nebula. At a rough estimate this larger area spans a distance of some 2,000 light-years and is some 50-times bigger than the Sadr region. Like other major areas of nebulosity (Barnard’s Loop) such a scale is way beyond the ability of my equipment and most others without resorting to a mosaic technique.

However, my interest in seeing and potentially imaging the bigger picture has been piqued and I have recently purchased a Vixen Polarie tracking mount, which can be fixed onto a camera tripod with a standard camera and lens in order to take long exposures without forming star trails. This set-up has two advantages over prime focus + telescope imaging: (i) it is highly portable and can easily be taken anywhere in a rucksack, and (ii) by using a camera lens of say <=50mm focal length it is possible to achieve a much wider FOV and thus photograph some of these very large nebulous areas in one image.

Alas the Sadr region is now moving on and it is probably too late to tackle using the Polarie mount but it will be something to look forwards to again next autumn and meanwhile Orion is just round the corner. Watch this space for developments!