Comet ISON (IV)

Comet ISON (C/2012 S1) is back, but not with a bang. It looks like the comet could not keep up the brightening rate and now the predictions for the maximum luminosity have dropped quite a lot (check out Seiichi Yoshida's awesome graphs and information about comet ISON). It can still surprise us, especially as it will pass so close to the Sun, but for the moment the hopes are not that high any more. 

The comet was still in twilight when I photographed it for the first time after passing through the conjunction with the Sun. Images taken on the 3rd and 5th of September. 

Image taken with the 50 cm telescope on top of the Argelander Institute for Astronomy. 

Comet PAN-STARRS (C/2012 L4)

  Finally, after 8 failed attempts to detect this comet, the ninth one brought luck with it!  I've tried during daylight, during sunset, during twilight and always that pesky cloud sat over it. But no more :)

    Initially I thought I lost it, but I was pushing my fingers just a little bit more (it was around -3C and windy), maybe I get lucky. Almost one hour of hunting through clouds later, I saw it! What a great moment! It was definitely much brighter than I expected it to be.

    Here are some pictures and a time lapse video, which is too short because not only my fingers were affected by the cold, unfortunately.... But I promise to have something of higher quality as soon as the weather gets better (which might be never, after all this winter was the cloudiest in 60 German years...)

    

     .... and the short time lapse can be seen below... 

Comet C/2012 S1 (ISON) (III)

My first color image of the awesome comet ISON. It's not very pleasing aesthetically, but it will get better with time. Check out the other two posts about it, I and II for more info, pictures and animations!

   The images were taken last night, on the 17/18th of February 2013, with the 0.5m Argelander Institute for Astronomy roof telescope, from one of the most inhabited regions of Europe, with the corresponding light pollution. 

Comet C/2012 S1 (ISON) (II)

Comet ISON is due to become one of the greatest comets to grace our skies during the last few hundreds of years. Possibly. Hopefully. Comets are unpredictable. 

In a previous post I took a few pictures of the comet while it was very, very faint and far away. Only a couple of months later it is much brighter, at magnitude 16.7 V and is getting brighter by the moment. I'd like to follow this comet in its journey through the solar system. 

It we add the images after we aligned them by the stars, the comet looks like a fuzzy streak: it is moving and it is not pointlike any more. 

If we add the images by centering all of them on the comet, we'll have star trails and a nice, little comet that already has a tail and coma. 

And finally, if we just center ll the images on the comet and then make a short movie out of them, we get this: 

    More to come as the German skies will get clearer in the spring :)

Comet C/2012 S1 (ISON) & Co

The comet season is here!

After the great comet of 2007, comet McNaught and the great comet of 2011, comet Lovejoy, we might be due to another Great One. Comet C/2012 S1 (ISON) was discovered on the 21st of September 2012 by Vitali Nevski and Artyom Novichonok, working with the International Scientific Optical Network (ISON). The preliminary orbit predicts that the comet will pass 1.8 million kilometers away from the Suns center and 1.1 million kilometers above it's surface on the 28th of November 2013.

This very close approach will melt and vaporize parts of the comet and it might develop a spectacular tail, with the potential of being much brighter that the Full Moon (some predictions reach magnitude -16). It is also well placed for observations from the Nothern Hemisphere, unlike the previous two great comets of this century. But let's not forget comet Kohoutek, which was another bright hope that ended in darkness: comets are notoriously unpredictable. 

Just one more interesting "coincidence". The orbit of comet C/2012 S1 looks quite similar to that of the Great Comet of 1680. It might be that they had the same parent body, which fragmented a long time ago. Hopefully we'll have the fun Newton had while he observed it. 

Right now it is beyond the orbit of Jupiter and looks like a very faint smudge at magnitude 17.5 V, but mark your calendars for late 2013 as you might be in for the show of a lifetime!

I observed this comet last night, with the 0.5m Argelander Institute telescope (as usually).

But there are other icy snowballs visiting the inner solar system :) 

One of them is comet C/2010 S1 (LINEAR), now shining at magnitude 13.3. It brighten to magnitude 13 or so in mid-2013 an then it will slowly fade away. A much more discreet visitor than comet ISON!

The second one is Comet C/2012 K5 (LINEAR), which will brighten to magnitude 8 in late December 2012 - early January 2013.  Right now it is at magnitude 11.1. Northern observers will have the best view, as it will silently slide from Ursa Major to Taurus in this time. As the comet was moving rather fast, I had to stack the images by centering all of them on the comet: that is the reason for which the stars look like trails while the comet looks just fine :) There was a gap in the observations and that's why the star trails come in pairs.

These last two comets were observed on the 24th of June 2012.

UPDATE: 13 January 2013
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The comet C/2012 K5 (LINEAR) has indeed brightened up to magnitude 8 during the last few months. An animation of the comet sliding among the stars can be seen below. The magnitude of the nucleus only as reported by Astrometrica is 14.8 V.