Bundle Up For Tonight’s Quadrantid Meteor Shower; K5 Comet Update

The Quadrantid radiant, or point in the sky from the meteor shower originates is found below the handle of the Big Dipper. I’ve shown the sky looking northeast around 2 a.m. Later that morning, the radiant will be high in the northern sky. Created with Stellarium

Yes Bobby, there is life after the Geminids. Last month’s meteor shower was arguably the best of 2012, but more are on the way. We start the year with a shower that originates from one of astronomy’s extinct constellation, Quadrans Muralis.

Although defunct, the group of dim stars was around long enough in the late 1700s to lend its name to the Quadrantid meteor shower.

The Quadrantids are reliable but forever a tease. Unlike most showers, which typically toss meteors our way up to several days before and after maximum, the Quads’ activity is limited to a span of 6 hours centered on the peak. That peak can bring a blast of up to 100 meteors per hour, but after that, the show’s pretty much over.

Quadrantid meteor on Jan. 4, 2011. Details: ISO 400, 30-second exposure and 8mm fisheye lens. Credit: John Chumack

This year’s maximum occurs at 13:00 Greenwich time or 7 a.m. CST tomorrow morning Jan. 3 for the Midwest. That’s well into morning twilight for the eastern half of the U.S. but still close enough to peak to make the shower worth watching.

Observers living in the western U.S. and across Hawaii and east Asia are favored because their skies will be dark for a longer time centered around the expected time of maximum.

No matter where you are, light from the waning gibbous moon will compromise meteor counts.

To watch the Quadrantids, set your alarm for tomorrow morning between 2 and 6 a.m. and face east or north away from the bright moon. Your eyes will adapt better to the darkness in those directions, letting you see more (and fainter) meteors. For mainland U.S. observers, the closer to dawn you’re out the better. I plan on rising about 5 should the sky clear.

Peter Jenniskens, senior research scientist at NASA’s SETI Institute, traces the Quads origin to the asteroid 2003EH1, a likely extinct comet. So yes, tomorrow morning we’ll be watching the remains of an extinct comet radiate from an extinct constellation. What could be more apropos?

Comet C/2012 K5 Monday evening Dec. 31, 2012 from Austria. Compare its appearance to the photo taken below in mid-December. The comet’s tail points northeast. Credit: Michael Jaeger

Did someone say comets? Rarely have I seen a comet’s appearance change so rapidly. C/2012 K5, the comet we visited in a blog three days ago, went from compact and bright to big and foggy in just a week. On Christmas morning, C/2012 K5 sported a small, bright head and a striking tail pointing northwest. Two nights ago I was in for a shock when I observed it again. The head had swelled into a big, hazy bulb with a bright, star-like center followed by a wide, much fainter, tube-like tail angled northeast.

There are at least two reasons for these radical changes – the comet was closer by a few million miles – 27 million on Monday night vs. 30 million on the 25th – and our viewing perspective is changing rapidly as C/2012 K5 dives through the plane of the solar system on about Jan. 6.

C/2012 K5 on Dec. 16, 2012 shows a small head and well-defined bright tail pointing northwest. Credit: Michael Jaeger

The comet follows a steeply inclined orbit, looping high above and plunging deep below the plane of the planets and sun. During the first half of December  skywatchers looked up above the Earth and solar system plane to see it. As C/2012 K5 plunges southward, we’re now seeing the comet more from the side.

Since a comet’s tail always points away from the sun, these changing perspectives – a combination of both the comet’s and Earth’s orbital motions – will continue to alter the tail’s direction and appearance in the coming weeks.

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

Despite the changes, C/2012 K5 remains bright enough to see easily in 8×40 binoculars from a dark sky. It’s a speedy beast too, leaping along at the rate of about 4 degrees per day or 1/3 the moon’s diameter per hour. When the bright core or nucleus happened to pass near a star Monday night, I could see it move in just 15 seconds at 64x in my scope.

Comets and meteor showers keep an amateur astronomer’s life interesting.

4 Responses

  1. Bob Crozier

    Your more recent photo of 2012 K5 is, I’m pretty sure, what I saw except, in my 4 inch telescope with a 24mm eyepiece, all I could see was the brighter central coma, and even that was fairly faint. From the orbit diagram, it seems to me that the tail should be pointed almost exactly away from us right now (that is, *behind* the coma from our perspective). Is that right? If so, that would be why it’s appearance has changed so rapidly. (btw: I think you skipped the word “change” in your sentence “Rarely have I seen a comet’s appearance so rapidly.” I wish I had a dollar for every time I have left out words when I’m typing!)

    1. astrobob

      Hi Bob,
      Hah! Yes, I left out ‘changed’. Thanks for pointing that out. I had originally planned the comet update for yesterday and had to do a bunch of editing to to fit it for today. Evidently I chopped a word in the process. I agree with you that the tail might be partially hidden by the coma. I did see a 1/2-degree-long tail pointing n.east on Dec. 31, though it was much fainter than on the 25th. As Earth and comet depart, it will be fun to see further changes.

  2. larsa

    I saw a bright blue meteor when i went outside just now! I immedietly checked on this site to see if there was a meteor shower, little did i know i did and its kinda rare! Thanks for having this site Bob!

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