Always keep the faith. AstroCamp comes with a clear sky guarantee*. However, despite a week of almost unbridled sunshine in the lead up to camp, rewarding those that arrived early, the forecast for Saturday through Monday was not promising. Certainly, mother nature antagonised those of us that arrived on Saturday afternoon with cloudless blue skies, but sadly by early evening a bank of cloud had rolled in, and looked likely to stay with us for the rest of the camp.
However, on Sunday evening I was reviewing every forecast I could find, praying one might provide some hope, and I found two that offered that glimmer. Accuweather in particular, and also the Met Office, suggested that we should experience clear skies between 1am and 4am. That was enough for me. Heading to bed at 9pm, I set my alarm for 12:15am. Looking out the window there was a distinct lack of stars, but nothing ventured, nothing gained, I got dressed and headed up to the campsite. That faith started to be rewarded around 1:15am when large gaps in the clouds started to materialise. By this time, I had intercepted John Wildridge on the common, owner of Bob the Dob, and informed him of the promise of starry skies. Initially, looking like this could be a session of chasing sucker holes, around 1:45am the sky suddenly cleared and were faced with thousands of tiny points of light, just waiting to be explored. Despite a 37% illuminated moon clearing the hills in the east, the Milky Way through Cassiopeia and into Cygnus was still visible.
We both quickly set up our scopes, aligning my finder on Capella. What did I write about keeping the faith? Reviewing the forecasts before camp, I decided to downgrade the kit I would bring to something smaller, taking my APM LZOS 115 f/7 triplet refractor mounted on the Tele Optic Ercole Alt-Az mount. Rounding out my equipment were four eyepieces, the Tele Vue 21mm Ethos (38x, 2.6o), the Tele Vue 14mm Delos (58x, 1.2o), the Tele Vue 7mm Nagler Type 6 (115x, 1.0o), and 4.5mm Delos (179x, 0.6o).
The Call of the Seven Sisters
There is no other DSO in the heavens that can be enjoyed with the naked eye in the way that M45 can. The closest Messier is quite beautiful appearing like a tiny saucepan in the sky. The power of a name leads many to believe that only 7 stars can be seen unaided, but I have managed 14 without too much effort, though this was under a Bortle Class 1 sky in Namibia. The view is even more fulfilling in a scope, and with The Pleiades already 44o above the horizon as the sky cleared, the lure of the seven daughters of Atlas was too much to resist. I popped in the 21mm Ethos and was rewarded with dozens of stars twisting and wrapping around the main “pan” stars. The proximity of the moon robbed us of any chance of glimpsing the reflection nebula that cradles the young cluster.
After enjoying the nearest DSO on Messier’s list, I panned over to Auriga to hunt down some its open clusters. Using Menkalinan (Beta Aurigae) as a starting point, I placed the star just outside the field stop of the 21mm Ethos, before panning about 14 degrees east and running straight into M38. An elongated cross asterism near the centre of the cluster drew my eye, and few stars exhibited a delicate orange hue in stark contrast to the blue-white of most of the cluster members. Using such a wide field, also encompassed small open cluster NGC 1907, though it was unresolved, appearing as a hazy cloud with some hints of granulation, the tell-tale signs of the approximate 30 members that make up this OC.
Switching to the 14mm Delos, I headed directly south about 6o and ran straight into the brightest OC in Auriga, M37. A very rich open cluster, my eye was immediately drawn to the topaz coloured star at the centre of the cluster, which was enveloped by an oval arrangement of stars. A dark lane just offset from the centre bisected across the cluster was another obvious feature.
Before arriving at Camp, I had intended to undertake a bit of an open cluster marathon, given how well placed the Milky Way is at this time of year. However, at 2:15am, Cassiopeia, which is home to more than 10% of the roughly 1,100 known open clusters in the Milky Way, was riding near the zenith, and with a straight through finder, would not be too kind of my neck. This did not stop me exploring the mythological queen for next 30 minutes or so.
I started with one of the most famous open clusters in the sky, NGC 457 (Caldwell 13), the Owl Cluster, or as I like to think of it, the E.T Cluster, such is the resemblance to Spielberg’s famous alien. While the two blazingly bright 5th and 7th magnitude stars which are the “eyes” of the cluster may not actually be cluster members, the head, body and out stretched arms, makes you feel like Elliot in the movie when the young alien looks for a final embrace before flying home.
William Herschel is perhaps the most famous astronomer of his generation, but his sister was certainly no slouch either. Not only the discoverer of several comets and DSOs, she was the first woman to have a salaried position as a scientist, and the first to hold a government position in England. In my opinion one of her finest discoveries is NGC 7789, which now bears the colloquial name, Caroline’s Rose in her honour. This spectacular OC is definitely a case of how did Messier miss it? Subtending a size on the sky equal to the full moon, this cluster contains almost 600 stars. In the 14mm, far more than 100 stars were contained in the central 50% of the field, with hundreds more unresolved stars taking on a nebulous appearance. There was a slight anticlockwise spiral structure seen in the cluster, given the impression of a delicate celestial flower.
My next two targets are quite large so I switched back down to the 2.6o field of the 21mm Ethos. Starting at Segin, which delineates one end of the “W” of Cassiopeia, I panned less than 6-degrees south-west to the star Psi Cassiopeiae, a beautiful orange giant. From there is was less than a 3o move south to the star 42 Cas, which is one of four stars (the others being 48 Cas, 50 Cas and 40 Cas) that form a trapezium around Collinder 463. The cluster itself extended to about 60’ in diameter and was a loose circular shape, of a few dozen randomly scattered stars. Towards the centre, a few of the more prominent cluster members formed an irregular pentagon, with two of the stars showing a subtle garnet hue.
If you use the same star hoping method to find the Double Cluster in Perseus as I do, extending a line made by Navi and Ruchbah in Cassiopeia, you have likely passed close by Stock 2, on your way to a 2-point answer in Sunday’s Spiral Arms pub quiz (NGC 884 and 869). One of 24 open clusters compiled by Jurgen Stock in the 1950s, this cluster appeared slightly larger than Cr 463. The cluster was slightly denser than Collinder 463, and benefited from a higher number of bright members. A central hexagonal structure appeared connected to a couple of spindles of stars which arched away from the core of the cluster.
It was at this point John whispered he had M33 in his scope. I walked over and ascended the step ladder to gaze into the cavernous 100-degree apparent field of his 21mm Ethos. Though the moon was robbing the view of some detail, the oblate ellipse-shaped galaxy was immediately obvious. With averted vision, I was just able to make out some hints of spiral structure in this nearby galactic neighbour.
Heading back to my scope, I switched to the 7mm Nagler for 81x and had two more targets in mind. Discovered by Pierre Mechain in 1781, M103 was the final DSO that Messier added to his original catalogue. Placing Ruchbah on one edge of the field stop, brought this small, 5’ diameter cluster into view. The cluster packs about 40 stars of magnitude 8-to-12 into its smaller area which created a very compressed impression thanks to the relatively low power I was using, with a distinct arrowhead shape of the brightest members superimposed on fainter members of the OC.
Last up in my mini-OC marathon was NGC 559 (Caldwell 8). It was an easy hop of about 3-degrees almost directly south from M103. The cluster showed a tight core of uniformly bright stars, which appeared dipped in nebulous material, but is in fact unresolved starlight. Just offset from the centre was a gentle arc of stars which curved back towards the core.
While pondering where to head next, John called out that he had Mirach’s Ghost in view. I was definitely not going to pass up an opportunity to see notoriously tricky galaxy NGC 404. The difficulty comes not from the surface brightness, but that it only lies 7 arcminutes from Mirach (Beta Andromedae), a red giant star, whose glare can hide this lenticular galaxy from view. Often when spotted it can be confused with an internal reflection somewhere in your optical train. Spending a few moments atop the ladder, with averted vision I was able to tease out a slightly brighter core, surrounded by a diffuse halo.
Returning once again to my scope, my journey would return me to the Milky Way, and my favourite class of objects, nebulae. The next few DSOs would see me visit both celestial nurseries and graveyards. Given the often-tenuous nature of these objects, and a magnitude -9.2 moon now more than 25o altitude, I screwed in my UHC filter in the body of the mirror diagonal to improve the contrast.
The first two targets were remnants of one-time galactic element builders. Located midway between Sulafat and Sheliak in the celestial harp, Lyra, Messier 57, floated against the back ground stars like a tiny, delicate smoke ring. The UHC actually brightened slightly the central “hole” of the ring, which is unsurprising as long exposure photos reveal glowing gas across the face of this famous planetary nebula.
Moving on from a celestial puff to a celestial bang, supernova remnant the Veil Nebula in Cygnus required dropping down to 38x of the Ethos 21mm. A simple hop from Glienah (Epsilon Cygni), one wing of the swan that dominates the summer sky. Placing that star on the edge of my finder, brings 52 Cygni to the centre of the field, which sits on top of the western arc of the Veil. The western arc is the fainter part of the Cygnus loop, but the UHC really helped bring the needle like strand into view. Shifting position slightly north centred the brighter eastern arc. A far more irregular shape was seen, as were some hints of twists and knots in the nebulous material.
Switching eyepieces to the 14mm Delos, I panned right across the sky from the west to the east with the hunter Orion, firmly in my sights. Deciding to throw a bit of caution to the wind, considering the proximity of the Moon, I aimed the scope at Alnitak, the lowest of three belt stars hoping I might glimpse the Flame Nebula. Considering this nebula is thought of as a litmus test for any attempt on the horsehead, it is a quite tricky object in its own right, and I did not fancy my chances. Once again, what was that about faith? While I could not make out much structure, and the dark lane that bisects the long axis was also absent from view, there was a definite ghostly presence just where I would have expected. Wanting a confirmation this was not averted imagination, I called John over. He peered into the eyepiece and quickly confirmed my observation before heading back over the Dob to try and see it in his scope.
Ominously thick clouds had appeared in the western sky and were moving quite fast, so there was probably little time left. One object was calling out for an early season viewing and that was M42. My first Messier through a telescope, and I suspect many other amateur astronomers as well, it never fails to impress. The 1.2o field was almost completely filled with glowing robes of gas. The two wings were particularly prominent, curling away and then back towards the main body of the nebula, and the four brightest members of the Trapezium were nestled at the centre of the glowing nebula.
Enjoying the view for a couple of minutes, I failed to notice the clouds had now hidden the western hemisphere completely from view. With only a matter of minutes left, I swung the scope towards Taurus, hoping to catch a glimpse of the remnant of the explosion that caught the attention of Chinese astronomers in 1054. Placing Zeta Tauri in the eyepiece, I moved up just over a degree to bring the ghostly apparition into view. I had less than 30 seconds before clouds hid the Crab Nebula from view. Sweeping quickly back to M42, I enjoyed the view for a few more seconds before it too was blotted out.
John and I considered what to do for a couple of minutes, but a quick check of the updated forecasts suggested we had seen the last of the stars for the night. We quickly packed down our scopes and hid them under their toilet tent shelters happy in the knowledge that we had almost two hours of unexpected stargazing. Walking home, I realised I had forgotten to target comet C/2018 W2 Africano in Andromeda, though those thoughts quickly washed away as it began to rain and my focus turned on getting back to the cottage as soon as possible.