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Have you ever seen cosmic dust with the naked eye?, is it even possible to do so from Earth?, the answer is a resounding yes. Our solar system is surrounded by an immense flattened disk of dust which rotates around the focal point of the Sun. This dust is composed of billions of particles from ancient comets and asteroids which have wandered through the inner solar system. These 'minor bodies' of rock, iron and ice have been doing this for billions of years before Humans even appeared on the planet, and they continue to do so today. Due to the gravitational dance of the planets and Sun these dust particles accumulate along the plane of the solar system and can be found on an invisible line in the night sky called the ecliptic which is the apparent path of the Sun and planets among the stars as seen from Earth. Looking towards the western sky after evening twilight, or in the eastern morning sky before dawn, a keen observer can see these dust particles in close proximity to the Sun as a giant pyramid of light streaming through the ecliptic, and since the constellations in this region are found within the Zodiac, the phenomenon is called the 'Zodiacal Light Pyramid' or 'False Dawn'. The best times of the year to look for it are during the Spring and Autumn Equinoxes when the path of the ecliptic is visible at a high inclination with respect to the horizon making the ZL easier to detect. To observe the ZL you need well developed dark adaption and a dark sky away from bright lights which is why many people have never seen it all. The good news is that you don't need to book a flight to Arizona because this elusive prize is actually easier to catch than you might think. Any country location which is relatively dark will reward you as long as you know what you are looking for.
Fortunately I have seen the ZL before many years ago while doing my pre-dawn comet hunting from my old home in Maghera. I recall spending hours with my eyes glued to the eyepiece, endlessly sweeping through the Heavens hoping to find the fuzzy glow of a new comet before anyone else in the world had spotted it. Those long, and often tough sessions guiding the 8" and 16" telescopes often presented other rewards at unexpected times at all hours of the night which I had not been looking for at the time. It's amazing hour keen your eyes and how well honed your dark adaption can become when you do this kind of observing night after night. After two or more hours of hunting I would often take my eyes away from the scope, take in a clean breath of fresh, and often frigid, air and rest while scanning the sky. It was during these unplanned breaks that I would be blown away by the detail in the sky. The Milky Way would glow brightly like a green cloud, the Gegenschein (related to the ZL) would jump out among the ecliptic as a huge green elliptical glow which was unmistakable, the deep sky objects like M31, M33, M41, M44, and countless others were so easy to see it was like childs play.
On other similar nights I would take a glance at the sky for a brief rest and would be both shocked and thrilled to see a bright aurora dancing across the sky in complete silence at 03.00 in the morning, sights like this felt so special that it seemed as if I was the only person in the world watching them in wide-eyed disbelief. Other nights produced spectacular Noctilucent cloud displays which looked so bright and alien that I was forced to abandon the telescope to find a better part of the garden to view them. Rewards were not isolated to those phenomena, other transient events like yelping Foxes, noisy Hedgehogs, silent swooping Owls, and the flashes of light among the stars from distant Summer thunderstorms were all part and parcel of those unexpected denizens of the night.
On one such night, just before dawn, I walked out to a good location and looked E before morning twilight washed out the stars, and it was then that I observed the ZL for the very first time. What shocked me was its brightness, this contrasted severely with what I had read in books and heard from more negative observers who speculated with high confidence that such an event was unlikely to be see from N. Ireland. The view I had that morning was spectacular, I could see, with terrific definition, the pyramid shape of the ZL slicing through the sky within Cancer and Leo, the ZL was vivid green and at the apex was planet Saturn, below, within the base, hung a beautiful slender crescent Moon with bright earthshine. As if this wasn't spectacular enough I glanced upward, and there it was, the Zodiacal Band connecting with the ZL, crossing through the Milky Way, then emerging through the other side in the W where it merged with the Gegenschein, this was special session which I have never witnessed since.
As with most kinds of observing, when one sees something for the first time, he or she tends to get better at catching it again because one is armed with personal experience and the elite knowledge of knowing what, where, and when to look. Since that morning I had observed the ZL on at least five other occasions in the pre-dawn sky, then many years would pass before I would see it again. That year was now, 2010. I had never observed it in the more light prone evening sky before and I had never photographed its delicate glow either, I had promised myself that I would do both these things in my life as soon as possible and that thought germinated inside my mind again on one cold March afternoon.
I was standing in one of my favourite country locations in Maghera, in a field on high ground, it was just after sunset and twilight was transforming the sky into strange colours of blue and gold while a bitter cold wind blew. I was watching planet Venus very low in the W which had just climbed out from the solar glare less than a week earlier. Being so close to the Sun the planet was nowhere near the brilliance it can reach during other apparitions, however my reason for being here was simply for the 'training' and to get an image of it within these difficult conditions. I had just purchased my first Digital Single Lens Reflex (DSLR) camera on Feb 18th, which was, coincidently, my birthday. The wait for the delivery seemed liked an eternity but when it arrived I found great joy, and some frustration, when I realized that I was at the bottom of a new learning curve which I needed to climb at a rapid pace. The camera was a Canon 450D (Rebel XSi) which had been on my wish list for nearly two years, and now I had it in my hands. I read the instruction booklet from cover to cover, watched educational videos on youtube, read so many websites on the camera until I was sick of the research, then began getting hands-on practice with it.
I began with clouds, sunsets, snow storms, landscape scenes, but finally decided that I need a more demanding subject which would put me through my paces while I raced against the clock. This I decided was the only way to learn how to use the camera in manual mode, there's simply nothing better than real experience. So there I was watching the golden ball of Venus, taking images, then 15 min's later the planet set below the dark outline of the Sperrin Mountains. I decided to stay a while longer to watch the stars come out, and it was during this time that I noted that the ecliptic was extremely high in the western sky, so high in fact and with such a favourable inclination, that I realised the ZL should be visible anytime soon. I did a quick calculation a week into the future, the waning Moon would be gone and the sky would be dark enough to catch it, it was the perfect set-up to see it and all I needed to do was find a good dark location and put in the time. It wasn't long before a plan was formed.
The next day I drove to Cookstown, walked into the local Argos store and flicked through their laminated version of the catalogue. I checked out the digital camera section, then narrowed it down to the Canon products. A quick scan down the list showed exactly what I had been looking for, a remote control shutter release, min's later it was bought. The maximum exposure time on most cameras is 30 sec's, that's more than enough for most night subjects, however the ZL was so delicate that a much longer exposure was required to increase the chances of detecting it at all. With a remote shutter, or cable release, one can then use the 'bulb' section on the camera and leave the shutter open for as long as one desired without the risk of camera shake. I now had all the tools required to catch my target, the rest was up to human effort and the weather.
The weather forecast was extremely encouraging, after an extreme Winter the weather had stayed friendly with no Atlantic influence at all. A large high pressure cell at positioned itself near Ireland and it showed no sign of moving for a long time. This meant dry sunny days and clear frosty nights with temps falling between -4 and -7 degrees C for inland areas over the next few nights so all was looking good. That day it almost seemed like Summer had arrived early with a crystal clear blue sky complimented by a high bright Sun. I was feeling energized by the bright day so I made it my goal to image Venus, the Zodiacal Light (if possible), and the International Space Station (ISS), I'm not a person for half measures so I wanted all three or else I would consider it a failure. I left home a while before sunset which gave me enough time to scout for a good location. I decided I would drive to the top of Slieve Gallion which was the largest mountain in the area, as I was sure the view from up there at night would be spectacular. I had been up there many times before watching thunderstorms so it was a familiar place, however destiny had different plans for me on this day. As I drove through the country roads with the long shadows of tall trees cast along the roads by the lowering Sun, I felt uneasy. I ended up taking the wrong turn and drove up the mountain wondering why the scenery didn't look like it had on previous trips. The road turned into a narrow trail which narrowed further to the width of the car, and soon I was bumping over trails covered with large rocks which banged the underside of the car which moaned and groaned in complaint. I had to stop half way up because the trail ended at a field and the car was close to being damaged, the last thing I wanted was a puncture. So I slowly descended the incline with my tail between my legs feeling rather foolish and defeated, this had been a bad start.
Once I got onto a secure main road again I felt more at ease and confidence returned with my familiar surroundings. The light was getting very low as the Sun set and dusk approached, shadows became longer and soon parts of the road were pooled in darkness forcing me to switch on the main headlights. The sky though looked wonderful showing off it's bright blue twilight in the crisp air, below, along the horizon, was an intense orange glow where the Sun had vanished and everything transformed into a magical scene. Through the windscreen I spotted Venus glowing proudly with its full -3.9 magnitude and it looked glorious. I decided that I would better find a location soon or my chance would be gone. As I drove though the deserted country roads my mind raced to find a location, after a few min's I came up with a last resort answer. I drove straight to Tobermore, approaching from the S side, and at the edge of town where the country begins I spotted the local Church, the stonework of which was illuminated by weak orange lights. To the L of this was the large graveyard which looked an eerie sight in the semi-darkness. I pulled into the car park, switched off the lights and did a quick recce on the place, it looked perfect. There was no one around however the tall gates to the graveyard were closed. The view from here was magnificent so I decided that I was going into the graveyard. There was a very large thick stone wall blocking the way, on the other side was a much higher drop onto the grass, I decided to be a little more stealthy about things because even though I was doing nothing wrong, I didn't want anyone seeing a suspicious looking dark figure with metal things which looked like a rifle jumping into the darkness so I waited until all was clear then climbed up the wall then jumped into the dark abyss on the other side while holding camera and tripod at the same time.
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I set-up the tripod, attached the camera, and caught my breath. I was positioned in the darkness within the shadow of the wall on dry hard grass. The temp was dropping rapidly and I noted my breath condensing in billowing silvery clouds as I tried to calm down my breathing. My bare fingers were already going red and turning sore from holding the tripod and the familiar world of cold and discomfort returned to me, I hated that feeling in my fingers, however it had been my companion all Winter so I was more than used to it, I keep telling myself during times like this that it's all part of the experience, after all if things always went according to plan in complete comfort with not personal sacrifice, then were is the satisfaction?.
In front of me where head stones, dark, silent, at peace. I had just enough light to see green moss covering the stone work in places. Looking due W into the distance was the dark outline of the Sperrin Mountains, the only sign of life where the scattering of small lights which belonged to the houses on it's flank. Venus looked spectacular sitting among the orange horizon haze with the pure blue sky aloft. I reckoned I had made a good decision by coming here because it's always nice to shoot from a new location. With numb fingers I activated the camera and began taking images, the live view on the 450D is brilliant for astronomical purposes. I simply positioned Venus on the LCD screen then pressed the appropriate button to magnify it x5 or even x10 times, then I could manually focus the camera until the planet looked perfect then take the exposure. The above is one of many taken during this twilight session, it was my favourite, Venus is visible just above the mountains. I stayed a while longer and watched it set behind the peaks. I suddenly began to fell uneasy, not because of the graves (nothing to fear here) but because I had the feeling I was being watched. Then I heard a Dog barking from a home nearby and it didn't stop as if trying to alert its owner to a third party in the area, I decided to leave while the going was good and made my way back over the wall which was great fun because it was twice as tall from the inside, and grabbing the hard wall with freezing fingers only added to the joy, however I was soon over with little effort and back in the car warming up and feeling highly motivated after ticking my first target off the list.
My mind focused and my eyes sharpened as I thought about the ZL, I was still thinking about the location but decided earlier in the day that as a default location I would choose the Glenshane Pass if the others didn't work out. Since it was too dark to try Slieve Gallion again I drove straight to Maghera, then diverted to the fly over and onto the main road as I began the slow climb up the Pass through the dusk sky which now had many more stars in attendance. The main road here is very dark and full of busy traffic which hampers dark adaption so I didn't have the luxury of admiring the sky as I drove due to safety regions. Once at the top, 1000ft above Sea level, I took the left turn before the Ponderosa, crossed the noisy Cattle grid, parked the car tight on the L hand side, turned off all lights, and relaxed as I tuned into the darkness.
Within min's twilight slipped away and was replaced by darkness, the sky was remarkable with great transparency and dark, proper dark, to the extent that your gaze cannot ignore the bright stars even if you were not interested in Astronomy. The stillness was broken only by the constant traffic on the road behind me as cars and trucks thundered along the pass oblivious to the peace and tranquility tens of metres away. Then, at 20.00 UT I saw the ZL for the first time in years!. I was expecting to have a difficult time seeing it, with at best only a weak signature among the stars, however the sight in front of me couldn't have been more grand. I could see a very conspicuous glow in the shape of a slanted pyramid in the W climbing upwards into the sky leaning over at almost a 45 degree angle to the NE (upper L), it looked colourless, similar to the pastel white-grey colour of distant galaxies as seen through a telescope. The base of the ZL was broad at the horizon where it contrasted with the sharp outline of the mountains, and could clearly be seen within the faint stars of Pisces near the SE corner of the square of Pegasus, from here it extended up through the ecliptic between the head of Cetus and Aries turning into a slender cone where it blended in with the sky not far below the Pleiades star cluster, and using my hands I estimated it as more than 40 degrees (80 full Moon diameters) in height. The more I watched the more obvious it became and as the sky darkened further it showed off in its subtle glory.
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20.08 UT, 18mm F/6.3, ISO1600, 154 sec's
I quickly got the camera ready, by now it was an easy and quick procedure which I had plenty of practice doing at night. Camera on, lens set to 18mm on manual focus, activated live view then zoomed in on Sirius, got a sharp focus within sec's, then disabled live view, switched to bulb mode and double checked the timer was set on remote. Then I selected ISO1600, composed the camera on the ZL with a small amount of the horizon and began taking exposures using the remote. The above is my very first image of the ZL, I was amazed to have picked it up at all so I was absolutely thrilled to get a result so quickly. You can see the ZL as a bright glow cutting through the centre of the image at an angle with Cetus and Aries on either side. To the upper R is M31 and M33. The headlights from the traffic on the road periodically illuminated the marsh and tall grass in front of the camera which you can see on the image, I had to stand at a strategic position to prevent those same lights entering the lens during the exposure. I was so captivated by the scene that I began taking image after image, trying out different exposure times and very quickly noticed what worked and what didn't.
Long exposures picked up more stars and more light so in theory you could get more detail in the ZL with a very long shutter speed, however the ZL drifts across the sky at almost the sidereal rate so not only will the stars be trailed but also the ZL itself which would result in a loss of shape and ending up as a broad glow, also any sky glow from lights would show up more readily. I found that despite being a very dark site visually, the camera still picked up light pollution from distant lights in Dungiven, and even the city of Co. Derry which are both many miles away. I liked the results obtained between 80 and 20 sec's, however it all depended on the quality of sky and LP. A wide angle 'fast' lens like the Canon 10-22mm would no doubt do a superb job on this subject. Having said that, I was still chuffed that I had picked it up so well, this was the reason why I bought a DSLR, and already the camera had proven itself to me, even with just the kit lens.
I watched the ZL until 20.35 UT for a total of 35 min's. I made sure to take plenty of time away from the camera and savour the visual view which is so much better than the majority of images I have seen. I then took images of Orion and Canis Major which were begging for attention then switched off the camera to give it a break. I was concerned about noise on the images however there was nothing of significance to worry about. I had enabled the 'high ISO noise reduction' but switched the 'long exposure noise reduction'' off, it was that cold up here that thermal noise was kept to a minimum. I was absolutely freezing, despite the calm conditions it was bitterly cold and soon my hands were red, shaking, and sore again, so I retreated back to the car and bathed in the welcome heat as I thawed out. When some kind of feeling returned I began the drive home again, only this time glowing with a sense of accomplishment. When I got home it took 1.5 hours before the feeling of pins and needles in my fingers and legs vanished, however it was worth it because I had achieved all three of my goals, and feeling invigorated I decided that I would try again the following night.
This was another glorious high pressure day with no clouds and a bright Sun nicely warming up the countryside where I spent the afternoon walking and doing some light hearted nature photography. I watched four huge Buzzards circling in the sky and calling to each other like Eagles, the group split into pairs then separated to hunt their quarry which was great to watch. I observed one of these hover silently in the sky like a UFO, then descend extremely slowly under perfect control in an almost unbelievable straight line towards a field, it seemed like a helicopter, the height from which it dropped from was impossible to estimate only to say that it was impressive. I assumed it chanced upon some unsuspecting prey in the fields. As I watched nature at work and soaked up the warm Sun I decided that I would return to Glenshane once again in the hope of catching the ZL for the second night in a row. After watching the disk of the Sun set below the mountains I had dinner, which I didn't enjoy, because I ate it too quick incase it held me up for my ZL plans, which where constantly going through my mind at the table. Dinner was followed by a good brew as I watched Venus from an upstairs window, then when the timing was correct, I got back in the car and drove back up Glenshane for round two.
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20.03 UT, 18mm F/4, ISO600, 80 sec's
I parked at the exact same location as the previous night, as they say, ''if it ain't broke don't fix it''. I arrived in plenty of time watching the twilight and listening to the radio as my eyes adjusted to the low light level. Despite being a great clear night I noticed that the transparency was reduced in comparison to the previous night with more moisture content in the sky which produced that 'gungy' look to the horizon which always accentuates the effect of distant lights and can destroy an image. The sky above this 10 degrees of gunge was great though so there would be no problems seeing the ZL at all. This time with more experience under my belt I was able to spot it much earlier at 19.45 UT exactly where it should be on the ecliptic and was able to watch it for 55 min's until 20.40 UT which was my longest sighting yet. On this night it looked striking with it's amazing slant through the sky like a wedge of twilight which shouldn't have been there since the rest of the sky was dark with no astronomical twilight glow visible at all. I was amazed to note that the ZL was significantly brighter than the Milky Way in Cygnus!, I was able to compare the two over and over again and was absolutely certain of this fact.
I just stood there watching the ZL feeling highly impressed by the visual sight and thinking how lucky I was to have such a good sky to see it in this manner. There are many astronomers who have never seen it in their lives, and many others from N. Ireland who would tell you that it can't be seen, never mind captured on camera, yet here I was soaking up its spectacular sight for the second night in a row. To see this phenomena, and get a photo from your own home country, is considered an elite subject to have 'ticked off' the list of experiences for any amateur astronomer. When I began imaging I thought it would be hopeless because another car had parked up in the distance facing directly towards me with it's dipped headlights violating the darkness, there was no way I could use a long exposure under those conditions. The car stayed put for a long time, however just as the ZL appeared it decided to leave, the timing couldn't have been better. No doubt the driver was wondering what I was up to when he drove past me towards the exit.
I tried many different exposures during this session, some even 5 min's in duration. The above image is taken portrait style to convey the vertical form of the ZL, which can be seen pointing directly to the Pleiades with open cluster M34 visible near the top within Perseus. The LP was more pronounced on the images due to the moisture so I had to adjust the levels and decrease the colour saturation in the orange and red tones to make it more presentable. I wouldn't mind trying a black and white capture at some future point. It was cold again tonight however it was nothing compared to what I experienced during the previous session, I wondered at the time if this was psychological because I had probably mentally prepared myself for a cold night in advance, the television forecast predicted another severe frost.
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20.20 UT, 18mm F/4, ISO1600, 152 sec's
I stood in for this capture to make it more personal, I didn't use a flash, the car lights along the road behind me and to the R illuminated me during the exposure. The cars were not much of a nuisance, however the large trucks were bad because of their powerful lights and slow speed which prolonged the glare, I kept my back to them the entire time for fear of messing with my dark adaption. I look transparent or ghost-like in the image because I stood within the frame for a min or so then walked back out which produces this effect. If I wanted to appear solid I would have stayed completely still during the exposure or used a flash. The brightness of the ZL and ambient starlight softly illuminated the patchy snow on the hills. The other light trail belonged to the second, and last car, I seen here during the session, luckily it didn't approach me and ruin the image. While the sec's ticked away on the camera I stood still and studied everything I could about what I was seeing, the brightness, shape, comparing the sharpness of the E and W side of the pyramid and watching how it drifted slowly to the N (R) along with the stars while slowly lowering in height.
It was easy to imagine this disk of dust, which we see from the inside looking out towards its edge-on plain, and imagine it crossing the entire sky from horizon to horizon and merging with it's other half-dome shape in the southern hemisphere, of course only the region close about the Sun is what we can see on any given night due to sunlight scattering off the millions of dust particles. To think that what I was looking at was billions of years old was absolutely stunning!. Scientists have recently discovered that the dust particles within the ZL is composed from 90% cometary material from the Jupiter family of short period comets along with 10% asteroidal material. Since this material was more abundant billions of years ago, the ZL as viewed from the young Earth would have been so bright it would have washed stars from the sky. Even today it's still very bright, if you swept up all of the dust particles and clumped them together they would glow much brighter than planet Venus.
High pressure was still dominating the weather which is very unusual for this time of year so I was treated to the third day in a row of clear skies and bright sunshine. It was around this time that the recent ZL sightings began generating some interest among observers in N. Ireland and soon others were watching in the hope of catching it. I emailed a few of my recent images over to Dr. Andy McCrea who is a high-up member of the Irish Astronomical Association (IAA) in Belfast and editor of the society's magazine called 'Stardust'. Andy replied to me in a very positive manner and was impressed that I had not only seen the ZL, but got images also which showed it so clearly. Despite many years of observing he had yet to witness this sublime phenomena for himself and had admitted that he had indeed been watching on recent nights without success due to the light pollution in Bangor where he lives. He informed me with great enthusiasm that he would meet me on the next clear evening in the hope of seeing it, and since March 9th was full of promise we decided to meet that night on the Glenshane Pass sometime after 19.00 UT.
This would be the first time I had observed with someone else in a long time so I was excited about the meeting, however I was also somewhat apprehensive because I didn't want Andy to drive all the way up here to be clouded out, or even worse, the ZL putting on a poor performance which would have left him disappointed and resulted in me sounding like I had exaggerated its appearance through the emails. I hoped the sky over Glenshane would deliver for the third night in a row so I crossed my fingers. I left earlier than usual during bright twilight and began the now familiar drive back up the mountain, I was delighted to be graced by a clear sky however I was somewhat concerned by the mucky appearance of the horizon which is what I had expected because high pressure weather always comes at a price. The cost of successive nights of HP is an increase in haze/murk which reduces the transparency and gives the sky that 'gungy' look, and this evening it was just like that. This murky quality would severely hamper any long exposure photography however it wouldn't affect the visual view with any great handicap so things looked promising.
I turned off the main road to the left as the tires drummed across the Cattle grid then pulled into my usual spot at the roadside. Andy was not there, I considered the possibility that perhaps he had got lost so I gave him a call on the mobile, he soon answered and confirmed that not only was he already there, but that he had also found a great spot further down the same minor road deeper into the darkness on high ground. I made my way in that direction using full beams to pierce the darkness and after several turns and a long narrow climb the lights reflected off another car parked on the road, I parked up opposite and got out, hoping that I had the correct car, it was Andy.
Not only was Andy there, so was his Wife, Shirley. There was no need for prolonged introductions because we already knew one another for years through two astronomical societies and correspondence via email. Twilight was deepening and the stars 'turning on' so we got to work. Andy set up his large refractor with heavy duty EQ mount with his Canon mounted on top so he could drive it on the stars. He was impressed with the location and said it was probably the darkest he said seen, before I arrived they had watched Venus dipping behind the mountains which sounded like a lovely sight. I set up my own camera as before, getting focus on Sirius using live view, then I was ready. There was a lovely pass of the ISS at 19.50 UT so we decided to watch it first.
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19.51 UT, 18mm F/4.5, ISO400, 149 sec's
At 19.45 I had spotted the ZL even though the twilight was still advanced at the horizon, however higher up the sky was darker and it was here that I could see the apex of its ghostly wedge, this was the earliest I had seen it of the three nights. Then the ISS appeared over the mountains low among the faint stars of Pisces and began to pick up in height and brightness at it moved eastward passing directly above Orion's Belt. The above image shows its trail among the stars from R to L during the long exposure. In the foreground is Andy's car, Andy is to the L and I to the R. The stunning open cluster M41 can be seen below Sirius.
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20.04 UT, 18mm F/4.6, ISO1600, 69 sec's
As darkness fell the ZL appeared exactly where it should be. It was then that Andy seen it for the first time. He admitted that he thought it would be difficult to see however was impressed by how obvious the glow was, and as time passed so did his level of awe. He could see it's full shape with averted vision and agreed that it was brighter than the Milky Way. I noted a subtle blue colour within the cone which was the first time I had seen anything other than grey-white during this apparition. You can see the ZL in the above vertical image pointing to M45 with M34 visible in Perseus. The flashing red navigation lights on a high altitude plane can be seen trailed below. Now is a good time to highlight the fact that the ZL is considerably more impressive with the naked eye than it seems on images, this is typical of large diameter low surface brightness diffuse subjects which require a wide contrasting field of view and a source that can handle the wide dynamic range, the human mark 1 eyeball is perfect for this.
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20.07 UT, 18mm F/4.5, ISO1600, 73 sec's
This image shows Andy with telescope and camera pointing towards the ZL as it slants upwards from lower R to upper middle of the frame. Thankfully it was not as cold as on the previous nights so it was a much more joyful experience to take in the snow without shivering. Andy came fully prepared though, he was practically wearing a balaclava. At this point fast moving car headlights raced down the road and stopped beside us, the owner walked over and took a great interest in what we were doing up here. It turned out the guy was interested in the sky and had observed it every clear night from the local area and began asking the kind of questions one would expect in this situation. Andy gave him a quick tour of the sky pointing our Sirius, Orion, Mars, and even mentioned the ZL. This was second nature to Andy since he always delivers talks on the night sky to a large audience at the society meetings so he was in his element and I enjoyed listening. Andy McCrea is a great speaker!.
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20.51 UT, 18mm F/4.6, ISO800, 208 sec's
The guy departed with his questions answered and left us to it. We observed meteors and engaged in astronomical conversation about future events while reflecting on past events like geomagnetic storms and comet Hale-Bopp. Andy told me about the time he met comet hunter David Levy and Stephen James O'Meara who's known as the man with the CCD eyes due to his excellent vision. I savored every word because I have been fans of these two famous US observers for as long as I have been observing. The ZL got our attention again, we got busy with taking exposures then stood still taking in the visual scene. We kept repeating ''there's no question about it, it's there''. It was great to share such a beautiful and delicate subject with someone else, Glenshane delivered after all and Andy was delighted he had made the effort and by how fortunate we were with the sky conditions.
We found that the human eye can get complacent and required 'stimulating' to keep it keen. To do this we simply turned away 90 degrees to the L and caught a distant light (which goes against the rules) then looked back W (R), when we did this the ZL popped into view with great clarity and well defined edges, particularly the S (L) side. If you don't believe me then try it, you might be surprised. Amazingly we were able to watch the ZL until 21.00 for a duration 1 hour 10 min's which was my longest view to date. When it's light began to fade and lower we turned our attention to the Milky Way which looked great arcing upwards from the dark country road on which we where parked. Here's one of several long exposures I took at the time showing Cygnus with M39 and Cepheus, the dark rift and other obscuration nebulae in the Milky Way can be seen with ease. The wriggly blue light is from Andy's camera LCD screen and the distant blue glow is from a distant car. It was time to leave, we said our farewells, shook hands, and parted feeling thrilled by the session, it was a great success. I felt sorry for Andy due to his long journey home because I would only be on the road for 15 min's before back in a warm house with a well deserved brew.
I wasn't even going to do anything this evening, I figured three days in a row was enough so decided I would give it a miss. Then I saw the television forecast which showed a weak frontal system passing down over the country the following evening bringing with it several days of cloud. I looked out the window towards the W and pondered what I should do although I reckoned my mind was already made up. The sky was clear as a bell and Venus looked like it was beckoning me out for a fourth night. I was that used to going out around this time of the evening that when I considered staying in I suddenly felt guilty and bored, my body clock was used to ZL time, and with such a great sky it would have been a shame not to take advantage of such a fine evening so I reluctantly decided to go back up again. I knew I had made a good decision because the sky was excellent, probably the best of the last four nights with not a single cloud visible, when I got into the car seat, switched on the ignition and heard the engine purr into life, I experienced that nice thrill of knowing I was on the hunt again, then I got a good feeling. I left in plenty of time during bright twilight and Venus was my companion, it almost felt like a guide as I just followed it to get W. The drive itself was leisurely and by then I felt like I could have done it with my eyes closed due to the frequency of my visits here throughout the Winter.
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20.25 UT, 18mm F/4.5, ISO1600, 58 sec's
This time I passed my usual spot and drove further into the hills and parked up where Andy and I had been on the previous evening. I half expected Andy to be there again but I was greeted by silence, dark hills, a long narrow dark road, and the ambient light of the stars and twilight glow transforming the mountains with subtle, yet magical colours. The sky was clear, the night cold, crisp, and calm. I had become so familiar with the ZL antics now that I knew exactly when to look, and being early I just relaxed in the car with the radio belching out eighties music which I loved. The twilight deepened so I turned off the radio and became one with the environment as the form of me and the car blended in with the night. I casually got out from the car and set-up the camera and tripod, all I had to do was check focus on Sirius and switch it off again as I stood and waited. This was magical, just the sky and me with no one else around, not even a single car, the view reminded me of those scenes of the Milky Way as seen from desert locations on television documentaries, the only thing missing was the howling of a Wolf.
The ZL suddenly was there, one min earlier and there was nothing, however now I could see it. At first it was the apex of the pyramid then within min's the remainder of its form seemed to 'fill in' as the sky darkened. The twilight was finally extinguished for good however a new glow had suddenly took its place towering up through the western sky dome at a crazy angle like a diffuse stationary search beam pointing to the Seven Sisters. It looked remarkable, it was the best view I had in the last four nights, it glowed with purpose and text book definition in a perfect elongated wedge, I could even see its perfect triangular base at the horizon within Pisces and there was even an unmistakable blue-green glow from within which contrasted with the dark background on either side. This truly was amazing, it almost felt like nature had decided to put on a spectacular show just for me. I went to work taking images, however this time there was no rush, I knew what to do so I just got on with it in a joyous peaceful state.
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20.27 UT, 18mm F/4.5, ISO400, 420 sec's
This image is a 7 min long exposure, taken less than 2 min's after the above capture from the exact same location. Both images show the ZL very well however the difference in star trail motion is striking. If you used a driven mount you could get away with very long exposures complimented by pin point stars, however this would be at the expense of a slanted horizon which I certainly do not like. I prefer the images to look natural, so another angle of attack could be to take shorter exposures and high ISO, say between 800 and 1600 for 30-60 sec's and stack the results together using online software which would produce a better signal to noise ratio and get a much better end result. However for the moment I was happy standing there taking single still images as the camera lens collected photons from this ancient light source. You might think to yourself, why would I go up so many times to see the same thing?, it's a good question and the answer is simple. The ZL will always look different every night for two reasons.
1) Atmospheric conditions in the form of variations in the transparency and seeing along with moisture content in the air, clouds, natural sky glow etc, or man made LP can make a big difference to what you see. Even the state of your health, hydration etc, can affect your eye sight and your level of dark adaption and sensitivity.
2) The Zodiacal Light itself does vary in brightness due to the fact that the disk of dust is not uniform in density, it stands to reason that a very dense section of the disk could be scattering sunlight the next evening and produce the display of a life time. So you never know what will happen and it always pays off to make that extra effort and take advantage of every opportunity.
The scene in front of me was spectacular, so impressive that I felt like ringing someone to tell them. I just stood there oblivious to the cold and watched that shaft of light glowing brighter than anything else with the Milky Way a sorry sight in comparison. Behind me, miles away, was the distant glow of lights in Maghera, of distant homes, some of the occupants of which were probably watching soap programmes on television, it seemed like a distant world down there, however up here I felt like I was standing within the transition world between Universe and Humans, and everything felt connected. I drove home that evening with a smile on my face.
Mother's Day. It had been four nights since I had last observed the ZL, we had been under the influence of persistent anti-cyclonic gloom which meant night after night of cloud. On the 14th I spent a productive overcast Sunday driving around the W and NW section of the Lough Neagh basin hunting out new storm chasing locations in preparation for Spring, I found an excellent location near Ardboe and spent some time studying the bearings and taking images showing the compass points. After this I drove half way up Slieve Gallion mountain and walked the remaining distance to the top which is a difficult walk for anyone, I went off the road and made my own trek around the flank of the mountain admiring the stunning view across the Lough, I added this to my storm spotting list although it would be a last resort, the kind of place that would be useful for catching night storms in the far E of the country. I wondered what the ZL would look like from up there at this high altitude?, I made a promise that I would try it at some stage, no doubt it would also be a good shooting location for NLCs and auroras. I watched as the grey stratocumulus scudded across the sky with crepuscular rays piercing earthward. The clouds yawned open and blue sky appeared around the relatively high March Sun, 22 degrees to the W was a beautiful sundog with rich colours sporting a splendid white tail. Closer to the Sun was a magnificent display of iridescent clouds with green, purple, and pink colours, it was the best example I had seen in two years. I noted that the sky was clearing so I began planning another nocturnal adventure once again.
Back in Maghera the Sun set in an immaculate clear blue sky with Venus standing to attention above as a silver ball higher in the sky than it had been in recent days. The clouds and weak frontal system had cleared the atmosphere from any atmospheric haze/moisture and the sky looked immaculate, I would not let an opportunity go to waste because this had the potential for my best experience yet. At 19.15 I hit the road, I was too excited to wait and just wanted to be in the zone so it wasn't long before I was back at my favourite spot on Glenshane. I warmed up in the car and listened to the radio for a while, during this time I was wondering why the car was shaking and what that strange noise was, I turned the volume down, my goodness it was the wind!, it was blowing hard with a roar and actually rocked the car on it's springs, that was a big shock because at ground level it was dead calm. I stepped outside, getting the door blown back into me, and instantly smarted with the bitter cold, this was going to be a nasty session!. On the plus side the sky was swept clean and looked perfect, the kind of conditions any observer would be proud to have.
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20.07 UT, 18mm F/4, ISO1600, 52 sec's
It took the sky much longer to get dark due to the growing length of day and there was still twilight visible in the W, when before it would have been dark. It's amazing what a difference a few days can make. Then I saw the ZL, and even though the twilight arch was still present, that wedge of light shone with incredible brilliance, like a lance of light shinning with pride as it stood to attention in the firmament with all it's glory. I honesty couldn't believe how amazing it was without repeating myself over and over. I could see its perfect shape and sharp slant from the very top to the bottom, the entire cone was a very obvious blue colour and it's size towered 45 degrees (90 full Moons) into the sky competing with the ecliptic stars on duty.
I watched with utter amazement as it's blue cone passed directly over the Pleiades star cluster, at this point words fail me because to appreciate it you had to have been there, this was the best sighting I've ever had in my life to date, and I soon forgot about the strong bitter wind. I set up the camera while the Zl-twilight combo stole the show and began taking images, this time I had to hold onto the neck strap incase an extra strong gust of wind blew the camera over, I even used my body as a wind breaker to reduce shaking from the elements. The above image is probably the best I've taken yet showing the ZL, twilight, strips of decaying cloud, and two distant planes approaching from the W, either from Derry City airport, or perhaps from a long flight over the Atlantic Ocean from the US. I was sure the pilots would have had a splendid view if they knew what to look for.
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20.08 UT, 18mm F/4, ISO1600, 63 sec's
Same scene one min later, only with 11 more sec's of shutter and the ZL looks brighter still. This is not far away from the visual sight except that I could see it beyond M45 with better shape, and that it was blue, however the camera picked it up as green which is fair enough because at times it did have a green hue visible. M31 and M33 are visible to the R. That glowing lance of light reminded me of a bright gas tail belonging to some huge comet with it's head below the horizon near the Sun.
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20.18 UT, 18mm F/4, ISO800, 195 sec's
I kept checking the time on my mobile because I knew there was an excellent pass of the ISS at 20.19 UT, and according to the website I checked before I left home it would pass directly over M42 (Great Orion Nebula) so I planned to catch it. I took on last ZL exposure, panned the camera to the L and composed my shot and waited. A new star suddenly appeared above the dark hills, it was the ISS, I pressed the shutter release then watched it move through the sky as a bright orange star directly below the ZL, then through Cetus, Eridanus, and into Orion itself where it went below M42. In the above image you can see its entire trail, however that's not all, look carefully to the upper R and you can see the top section of the ZL glowing as it touches the Pleaides. There's also a fainter satellite crossing through the northern portion of Orion which meets the ISS trail to the L of frame. I got a text from John McConnell, he had just captured it going directly through M42 from Maghaberry, just goes to show what a slight difference in latitude and longitude can do. It's a good example of Parallax which is very obvious with close range objects in space.
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20.24 UT, 18mm F/4, ISO1600, 65 sec's
This was one of my last captures of the night taken well into the session. There's no mistakening the ZL at all. I thawed out in the car again then began the drive home while taking a detour to hunt down aurora observing locations then made it back just in time to watch the new BBC television series called 'Wonders of the Solar System' by Professor Brian Cox which is a great programme. I had now seen the ZL on five different nights within a week making this a great personal record for me. On television Brian Cox stood on the edge of a vast rock face in some far away dark corner of the world as the Milky Way glowed and moved across the sky in time lapse fashion, it seemed I had experienced something just as special and remarkable from Glenshane on the very same night, and that's when I realized that all was well and life was great. I plan on going back up again during the next dark period during April and perhaps even get a chance at imaging from Slieve Gallion before the Summer nights return with twilight all night long. This is my first astronomical image account in a very long time so it feels good to get something different added to the website again, and all being well, I plan on catching many geomagnetic storms and NLCs this year to show off what the night sky can do. This is a long account which has taken me five nights to complete, whether you consider it good or bad, I hope you at least enjoyed it and learned something new. More importantly I hope you feel inspired to make your very own first observations of the incredible Zodiacal Light, you won't regret it - I promise you. Thanks for reading.
Martin McKenna