As I described in an earlier piece, the Messier catalogue tends to be the starting point for many amateur astronomers. Most Messier objects are fairly easy to find, and encompass a wide range of objects (galaxies, star clusters, nebulae, etc). But once you’ve ticked them all off, what then? For many, the next structured list of astronomical objects to hunt for are in the Caldwell catalogue, compiled by Sir Patrick Alfred Caldwell-Moore. Of course, the more adventurous can go straight to the Herschel 400, or even the New General Catalogue (NGC).
Conceived of as a list of beautiful and interesting objects to observe (unlike Messier’s list of things to avoid in your hunt for comets – that always makes me smile!), the Caldwell catalogue contains a diverse range of astronomical objects, including some that Messier should, perhaps, have included (such as the Double Cluster in Perseus, and the Helix nebula). Many ‘C’ objects are actually located in the southern skies, so of the 109 listed, only approximately 70 are visible from southern England.
Sir Patrick’s aim was that all the objects in the list should be visible using a four-inch or larger telescope (on a dark, clear night), and they range in difficulty from the naked-eye obvious to the much, much more challenging. I’m currently on 25, and I have to say, I’m relishing the challenge. In the main, and with the exception of the bigger/more obvious targets, C objects are trickier to find than Messiers. They do, however, help you hone your star hopping skills, and require you make the most of your equipment and experience. The end result of searching for a particular galaxy, for example, may well be a small fuzzy patch, but the achievement of finding it, and the realisation of what and where it is, makes the experience well worth while.
The night of February the tenth was a fantastic opportunity to add to my tally. I’d put the scope outside in the car to cool for about 7.30PM, and by the time I was set up at my observing spot just over an hour later, it was pretty much fully acclimatised and I was ready to go. My first target was actually a Messier object: M46 in Puppis. I’d seen this wonderful open star cluster before, but I’d recently learned that there’s a planetary nebula (NGC 2438) in the same view, and I’d never noticed it before. It has to be said, the sight was incredible. The background stars of M46 were like diamonds, and the planetary nebula in the foreground stood out very clearly, and responded well to higher magnifications.
I spent the majority of the rest of the evening concentrating on the constellations of Canes Venatici, Coma Berenices and Hydra. Caldwell 26 is a slender, edge-on spiral galaxy around 10 million light years away in Canes Venatici. In the eyepiece it’s a very faint wisp. Next up was Caldwell 32: the Whale galaxy. Although further away than C26 (at around 22 million light years), the Whale appeared larger, brighter, had a very obvious ‘whale’ shape, and even had a hint of detail (with some darker patches and clumps visible). There’s a bright star in the foreground, superimposed on the galaxy, and this adds a wonderful depth to the view. NGC 4656, a barred spiral galaxy, also known as the Crowbar, is part of the cluster of galaxies which includes the Whale. It’s ‘crowbar’ or ‘hockey-stick’ shape is very obvious.
C53, known as the Spindle galaxy, lies 32 million light years away, and can be found in the constellation of Sextans. It’s obvious how it got its name, appearing as a thin wisp with a brighter bulge in the middle. Next up was C48; a spiral galaxy lying in Cancer, and an incredible 55 million light years away! It appears as a small, circular patch in the eyepiece, with no discernible detail.
My last stop on the galaxy tour for the evening was NGC 3640 – a small and rather unimpressive, round, fuzzy galaxy in the constellation of Leo. However, at around 80 million light years away (!) I’m pretty sure this is the most distant object I’ve ever seen. To see something that is so far away, with the naked eye, is staggering (bear in mind that 1 light year in miles is 6 followed by 12 zeros!).
Jupiter had been been visible above Giant Hill all evening, and by about 11PM was well clear of the atmospheric murk. At 240 times magnification the planet was stunning, displaying clear swirls and whorls in the cloud bands. This was easily the best view of the planet I’ve ever had (it was almost photographic), and I can’t wait to get out and view it again.
Work in the morning meant that I had to finish off by about 11.30, so I spent the remaining time on some familiar targets: the Orion nebula (the structure and stars all incredibly clear), the Double Cluster in Perseus (often described as a scattering of diamonds on black velvet), and my first globular cluster of the year: Messier 3. The latter, at 240 times magnification, was spectacular. Half a million stars packed together in an eight billion year old star cluster, 34 thousand light years away …
All in all, a pretty mind boggling evening!
What’s up?
You should really check out Jupiter at the moment. Although not at opposition until the 8th of March, it’s big and bright enough right now as to be spectacular. Messier 3 is clearing the eastern horizon by about 8PM, and by 10PM should be very clear and sparkly. You can find it by looking straight up from the very bright orangey/red star Arcturus in the east. 10×50 binoculars will show it as a small fuzzy ball, but a moderate telescope (4-5 inches and up) will resolve individual stars.
Clear skies!
Kevin Quinn is an amateur astronomer based in Cerne Abbas. He is the proud owner of a ten-inch reflector, a small refractor, a case of eyepieces, and a couple of pairs of binoculars. He tweets via @CerneAstro, and blogs via theastroguy.wordpress.com.
©Kevin Quinn
