C/2012 K5 – An Evening Comet Worth Chasing

Comet C/2012 K5 photographed this morning Dec. 16, 2012 from Austria. Two tails are visible – the obvious one and a faint dust fan to the upper left of the comet’s head. Credit: Michael Jaeger

Sure I love the moon. Last night’s walk with the dog wouldn’t have been nearly as romantic without it. But tonight the moon won’t rise for an hour after twilight ends. That means the return of dark skies and the Milky Way. It’s also a perfect time to follow what has now become 2012’s brightest comet – C/2012 K5 LINEAR. Just in time it would seem!

This picture of Comet C/2012 K5 on Christmas Eve morning was made with an 8″ telescope and nicely shows the comet’s two tails. Credit: Gerald Rhemann

On Christmas morning I saw it in plain old 8×40 binoculars as a fuzzy glow near Big Dipper’s Bowl. Through a 15-inch telescope the comet was sheer beauty with a compact bright head and tail nearly as long as the full moon is wide (1/2 degree).

Currently shining around magnitude 8.5 and moving swiftly as it makes its closest approach to Earth tomorrow, C/2012 K5 is now out during convenient evening viewing hours.

The comet moves swiftly through Auriga and n. Taurus in the coming nights. Watch especially on Jan. 3 when it passes next to the bright star cluster M36. Stars shown to mag. 7.3 and map dates are for 7 p.m. CST.  Right-click, save and print a copy for use at the telescope. Created with Chris Marriott’s SkyMap software

You’ll find it still around 8-8.5 magnitude during the coming week as it skims through the bright constellation Auriga not far from Jupiter.  I have to be honest – while visible in binoculars from a reasonably dark sky, it’s no great shakes, just a patchy glow. Through a small telescope however, you’ll see the little head and at least a hint of the tail stretching off to the west.

Consider the comet a warm-up for the brighter fare coming this March when C/2011 L4 PANSTARRS makes its appearance in the evening sky. You can read more about that one  and another bright comet in my best sky events of 2013 blog.

C/2012 K5 orbit is steeply inclined to the plane of the solar system, which is why it’s been visible in the far northern sky of late. Now the comet’s rapidly moving southward as it plunges through the plane. Credit: NASA/JPL

C/2012 K5 LINEAR was discovered earlier this year by the automated Lincoln Near-Earth Asteroid Research (LINEAR) project. The joint effort by the Air Force, NASA and MIT’s Lincoln Laboratory uses a 1-meter (39-inch) telescope to discover and track Earth-approaching asteroids. In addition to thousands of new asteroid finds, the survey has picked up a few comets along the way. K5 was discovered on images taken May 25, 2012.

Facing east around 7 p.m. local time Dec. 30. Use this wide view map to locate Auriga and then the more detailed view above to find the comet. Created with Stellarium

The comet comes closest to Earth on Dec. 31 at a distance of 27.3 million miles. Now at its brightest, the comet will soon fade after about the middle of January. Stop by for a look the next clear night.

21 Responses

  1. Bob Crozier

    I have been trying to sneak a peak at this comet for weeks, but (as is normal for the north Okanagan at this time of year) we have not had a clear night. I had about a ten minute window to try and locate it early one morning (3:30 before I went to work) a couple of weeks ago. But either I couldn’t find it or I saw it and didn’t make it out to be a comet in my 4 inch telescope. If I am really lucky, I just might get to have a peak tonight as there are a few patches of blue out there right now! The really sad part of this whole story is that this will likely be what happens at this time next year, too, when c/2012 S1 ISON is going over head! Maybe I can move to Saskatchewan before then? Christmas holiday??

    1. astrobob

      Hi Bob,
      Don’t give up. I bet you’ll find it this time. It’ll have a nice run now in the evening sky early or late with lots of time before the moon comes back. Let us know if you spot it.

      1. Bob Crozier

        Well, I got out for about 40 minutes tonight before it clouded over again. I think I found it. It looked to me, in my 4 inch telescope with a 24mm eyepiece, like a very faint and rather diffuse nebula. I could not make out a coma or even an elongated shape. But according to your star chart (thank you very much for that, btw!), I don’t think there should be any nebulae right there. I do need to get better eyepieces for it. That might have helped.

        1. astrobob

          Glad you found it Bob. I just got in from looking at the comet myself. It’s just as bright as on the 25th but it’s changed dramatically in appearance. Larger now with a wide, fainter tail. I’ll be updating tomorrow with new pix.

  2. Tim Hutton

    Thank you for posting this. I have also tried to find it while it was near Ursa Major, as per your suggestion, after I failed to spot the one in early Dec. in the area of Mars. Yeah, I’m the guy who’s still never seen a comet. I had just tried with binoculars because it had been too cold to set up my telescope. It probably wasn’t bright enough. Passing through Auriga now, I can look right after sunset before it gets too cold out. Now I just need a clear sky.

    1. astrobob

      I’ve found that thin cloud will make it tough in binoculars, but with a clear, dark sky, you should be able to see a little fuzzy patch. How big is your telescope?

      1. Tim Hutton

        I have an Orion SkyQuest XT10g that I’m still learning how to use. It gets better with each time. I need more patience I think. I’m completely amazed at what I’ve seen thus far. Although it’s not ideal for astrophotography, I’ve been playing around with connecting my Canon T3i to it as well. I’ve taken some great shots of the Moon and some so so shots of Jupiter. I’m still trying to improve on that though. I wonder if I can get a picture of the comet. Haha- I better just concentrate on seeing it first.

        1. astrobob

          A 10-inch should do nicely on the comet. As you’re aware, once you get past the bright planets, astrophotography get more demanding and sometimes more expensive!

          1. Tim Hutton

            I think I found it tonight. Like Mr. Crozier’ post above, all I saw was a fuzzy patch, so I’m not sure. I had to quit faster than I wanted to due to the cold. What a crazy hobby.

          2. astrobob

            Congrats! The cold can hurt. And remember, it’s only crazy until you’ve done it enough to make it seem like normal 🙂

  3. I tried to photograph K5 on the 29th before moonrise and guess I aimed my camera a bit too far north. I’ll try tonight if skies allow. With 127mm lens, the comet is quite visible in 2 minuted guided exposures (iso = 1600). Anyway, the link above was taken on 17 Dec from Santa Fe, NM at ~6767′ elevation.

  4. Robert

    Thanks for the star map Bob! After many successive cloudy nights here in southern England I finally got to observe it last night. I found it almost straight away thanks to your map, and could see the comet head and gas tail through my 8″ reflector. I hope the skies will be clear when it cruises past M36. Should be a beautiful sight!

  5. David Chaloux

    I observed this last night Jan 8th, 2:55 UT in a 102mm refractor. It has now faded and is not as bright as the Crab Nebula, although similar in size. A hint of a tail was still visible but just barely in this telescope. It was a pretty difficult object. Limiting magnitude was roughly 5.8 with the naked eye.

    1. astrobob

      Thanks David for writing. Yes, it is fading now. I could still see it in my 8×50 finderscope as a mushy haze but overall it’s noticeably dimmer now than a week ago.

      1. David Chaloux

        I took another look on Jan 9th, 3:49 UT. This time I was using an 8″ SCT under skies with a limiting magnitude of around 5.2. The view was not really substantially better than that in the 102mm refractor the night before. As with the refractor, a star like nucleus was visible (something I forgot to mention for the previous night). It was very similar in brightness to nearby star TYC 00695-0155 1 (Mag 9.76) when the star was defocused. While by no means a hard object in this scope, it wasn’t very impressive.

        1. astrobob

          Hi David,
          Thanks again for the report. I would agree – under your circumstances with an 8-inch it would not appear impressive though I’m surprised you didn’t see at least the start of a tail in the form of a fan extending from the coma. I’m watching the comet under skies with a limit of 6.5 using a 15-inch. It’s fading for sure but the view of the misty tail was still very nice. Again, different conditions. We all appreciate the reality check!

          1. David Chaloux

            I actually did see a hint of a tail again last night, but I couldn’t be absolutely positive it was there. The night before I was more sure of it, which is why I mentioned it there. Although I was using a bigger telescope last night, the skies were enough worse that for something as low surface brightness as the tail, it was getting washed out in the haze (which is why the skies were roughly 5.2 instead of 5.8). To be fair magnification was also somewhat different. Last night I only used 85x whereas the night before I was at as much as 143x.

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