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Tue, 26 May 2015 - Comet Lovejoy 2014 Q2 Passes Polaris

Comet Lovejoy as it appeared on May 22nd, photographed from the Langdale Valley. Polaris is the bright star, top right. Lovejoy is the little green smudge near the centre. Image: Stuart Atkinson

Comet Lovejoy 2014 Q2 has been delighting, frustrating and fascinating UK sky watchers for five months now, but its show, and its grand tour of the northern sky, are coming to an end. It is fading now, and will soon be too faint to see with binoculars. Then only telescope-owners will be able to follow its retreat from the Sun, until they eventually lose it too. We will all be sorry to see it go, but it will leave us with many happy memories and even more glorious photographs when it is gone.

Comet Lovejoy seems to have been in the sky forever. Having crept up from beneath Orion and into the northern sky at Christmas last year, when it was just a tiny smudge in binoculars and telescopes, it then steadily climbed and brightened. At its peak, as it arced up towards and then past the glittering stars of the Hyades and the Pleiades, Lovejoy was a naked eye comet for northern hemisphere observers - a green-tinged star with a stubby, misty tail behind it. Now, after sailing through Cassiopeia in April, Lovejoy is fading but is still, remarkably, bright enough to be seen with a pair of binoculars.

It is now drifting serenely up towards Polaris, the Pole Star, and that means it is very easy for even the most inexperienced comet hunter to find: if you know where to find Polaris, you can find Comet Lovejoy as it heads away from Earth and returns to the cold, lonely depths of the outer solar system. It won't grace our skies again until the year 15382!

So, if you haven't seen Comet Lovejoy yet, this is the perfect time - and maybe your last chance - to try and find it. But before I show you where to look, a quick word about what you're looking for.

At its best, back in late January/early February, Comet Lovejoy was clearly visible to the naked eye as a misty smudge in a dark, light pollution-free sky, and was a beautiful sight in binoculars and small telescopes, when it looked like a big, out of focus green star with a faint, delicate tail teased out behind it. Lots of beautiful pictures were taken of it around that time; long exposure photographs taken through telescopes revealed beautiful detail in its tail, twists, kinks and feathers of violet and blue invisible to the naked eye. Now Lovejoy is a shadow of its former self. It still looks like an out of focus green star in binoculars, but a small, faint one, and the tail has gone, the final traces of it only visible on long exposure photographs. But it is definitely still worth looking for.

So, to find Lovejoy you first need to find Polaris. Most people reading this page will already know how to do that, and they can just scroll down to the finder charts which will show them where to and start hunting on the next clear night. But if you don't know how to find Polaris (and if you don't, don't worry. Everyone has to start somewhere. Just remember that every single person you have ever seen on the pages of one of the monthly astronomy magazines, peering into or taking pictures through a cannon-sized monster telescope, was once an absolute beginner who didn't have a clue where ANYTHING was!) here's how...

We're going to start off by looking at the sky around an hour or so after sunset. At that time the sky will still be too bright to see any actual stars, but you will notice two bright "stars" low in the west. These are actually two planets, Jupiter, on the left, and Venus, on the right.

They are slowly coming together in the sky at the moment, and will meet at the end of June when they will be so close together they will both fit in the field of view of a pair of binoculars. But that's in the future! Right now we can use them to help us find Polaris, and Comet Lovejoy. Once you've found Jupiter and Venus, look over to the right of Venus and you will see, a short distance away, just above the horizon, a gold-coloured star. This is Capella, brightest star in the constellation of AURIGA The Charioteer. Look to the right of this star and you will see a small "W" of stars. This is the constellation of CASSIOPEIA, The Queen, and once you've found it you're just a short hop away from Polaris.

Mentally draw a line between Cassiopeia (it doesn't matter which star of the W you use) and Capella, and then picture that line as the base of a triangle. Now look up at where the to of that triangle would be - and you'll see a star. Not an especially bright star, just a star on its own.This is the famous Pole Star - Polaris. This is the star Comet Lovejoy is about to drift past.

( Of course, there's another better-known way of finding Polaris, by using what is probably the most famous pattern of stars in the whole sky, north or south of the celestial equator: the Plough, or The Big Dipper as it's also known. You just use a pair of its stars - appropriately known as "The Pointers" - to hop to it. But at this time of year the Plough is very high in the sky for northern hemisphere observers and not as obvious or easy to spot as it is at other times of the year, so that's Plan B if the Venus-Capella-Cassiopeia star hop doesn't work for you. The chart below shows you how to find the Plough and, from there, Polaris. Basically, face Cassiopeia, then tilt your head back so you're looking at the zenith right overhead, and you'll see The Big Dipper just off to the left, looking rather like the hook of a coathanger. It's just a quick star hop from there to Polaris...)

But back to the comet! Having found Polaris, all you have to do to spot Comet Lovejoy is scan the sky around Polaris with your binoculars or small telescope and look for something that looks like a small, smudgy star. The comet is moving towards Polaris as I write this on May 26th, a little closer to it each night, and will eventually cruise past it. Below you'll find charts showing where the comet will be at approx 11pm on each night for the rest of the month, and you can use them to track down the comet.

Unfortunately, with the Moon brightening in the sky, and the Sun setting late in the evening, the comet will look dimmer than its actual magnitude of 8 suggests, and you might struggle to find it at first, especially if you live in a light polluted place. But give it a go. As I always tell the members of my astronomical society, "If you don't look you'll definitely see nothing!" And if you don't find it right away, keep trying!

Comet Lovejoy has been, as its name suggests, a joy to follow on its epic grand tour across the sky. But soon it will only be visible through large telescopes and to cameras, so if you are gifted with a clear sky after dark on any night before month's end, get out there and try to see it. And wish it thank you, and farewell...

Stuart Atkinson


Added by: Stuart Atkinson