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Sat, 02 Jan 2016 - Comet CATALINA drifting past Arcturus as year ends...

As 2015 draws to a very wet and windy close, Comet CATALINA US10 (hereafter called simply "Comet CATALINA" to save wear and tear on my fingers) is still hovering just below the magnitude 6 mark, meaning it is a good comet for observers with binoculars and telescopes, but not bright enough to be seen with the naked eye. So, anyone wanting to view CATALINA will have to be looking at it through something, preferably from a dark sky location.

Now, even if you have a pair of binoculars or a small telescope, CATALINA is not exactly going to fill their field of view, because it is visually a very small object. And that means finding it is quite a chalenge for the less experienced or even first time observer -

At least, it has been. That's about to change.

As a late Christmas present to us all, Comet CATALINA is going to end 2015 by drifting right past one of the brightest and easiest to find stars in the whole sky, which will make CATALINA itself extremely easy to find, even if you don't know the sky particularly well. So, if you were bought a telescope or a pair of binoculars for Christmas, this is going to be your chance to christen your optics with the light of their first comet!

So, where do you look?

First, you have to be going out a few hours before sunrise, because CATALINA is a morning object. No need to go out ridiculously early tho - go out too soon and the comet will be so low in the sky it will be dimmed by all the murk lingering above the horizon - four or five am will do! Obviously, as with most things in astronomy, you want to find yourself an observing spot with few lights and a "big sky", because that will be a huge help, but for CATALINA as long as you have a clear view of the eastern sky that will be fine, because that's where the comet is, in the east, to the lower left of where Jupiter is shining brightly like a small diamond. In fact, it is shining to the lower right of THE most famous pattern of stars in the northern sky, perhaps the whole sky: the Big Dipper. The bright naked eye star Arcturus shines to the lower right of the Big Dipper on winter mornings, and as you can see from this chart, CATALINA is currently very close to Arcturus.



Finding Arcturus (and with it, Comet CATALINA) is easy - you just use an old astronomers' trick and, continuing the curve of the Big Dipper's "handle" you follow the arc to Arcturus...



So, that's where Arcturus is, and as 2015 ends, and 2016 begins, Comet CATALINA is going to approach and then pass this beautiful bright star. Here's where to look for it over the next few mornings.



That's where CATALINA will be as 2015 turns into 2016 - and then? It just goes sailing past...

Having followed all those instructions, what can you expect to see if/when you track down CATALINA? Basically, a fuzzy, misty, out-of-focus star, with a hint of a tail... perhaps. At the moment the Moon is quite close to CATALINA in the sky, which dims it somewhat, but it is still very much worth looking for: it's not often a comet passes a really bright star like this, making it easy to find even for absolute beginners, so we should all grab this rare opportunity with both hands.

Hopefully some of the people who were bought binoculars or telescopes for Christmas will take them out and train them on Comet CATALINA over the next few mornings, because we don't know when another comet this bright will appear. If you;re one of them, or already an experienced comet watcher, good luck tracking down Comet CATALINA as we tock off the last few days of 2015 - and cross our fingers for a 2016 blessed with a truly Great Comet. We're long overdue one!


Added by: Stuart Atkinson