Comet Hunting – 46P/Wirtanen

This month brings the excitement of a comet hunt, as Wirtanen 46P reaches closest approach on December 16th.  This is a relatively small comet (1.5km across) with a period of just over 5 years.  However Wirtanen is known to produce a relatively large tail for its stature, so it’s definitely one to look out for.  In mid December it’ll be positioned between the Pleiades star cluster and red giant star Aldebaran in Taurus, so will be relatively easy to locate in the night sky.

Reports of naked eye sightings and some photographs are already emerging online despite the current low altitude of the comet at high norther latitudes.  However its vantage will steadily improve as we head into mid December, although Moon conditions will become less favourable then, so time your hunt well.

Wirtanen should be observable in a wide-field telescope or binocular view, and possibly naked eye under very dark conditions.  You could also try locating it by taking a 10-30 second exposure in your DSLR camera.

I’ve put together a short video to help you locate it over December.   Clear skies!

The Leonids

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The radiant of the Leonids is in the constellation Leo, but you don’t need to look in that directions to see shooting stars.

The annual Leonids meteor shower is due to peak over the weekend between 17 and 18th November 2018.  Although the waxing gibbous Moon will diminish conditions somewhat it will still be more than worthwhile heading out somewhere dark to observe them.  Over the peak as many as 10-15 meteors per hour may be visible.  Occasionally meteor showers will erupt into storms, as was the case with the Leonids in November 1833, when 100,000 meteors per hour rained down over an entire evening!

The shower is caused by the Earth colliding with the debris left behind by comet Temple-Tuttle, a short period comet with a period of 33 years.  Temple-Tuttle is due to swing past the Sun again in May 2031, when it will once again deposit fine dust trails behind it, seeding future generations of meteor showers.

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The tail of a Comet always points away from the Sun.  Debris from the Comet’s tail produce most meteor showers, as the Earth intersects the fine dust trails in its annual orbit around the Sun.

Observing the Leonids

You don’t need any special equipment to view a meteor shower, in fact binoculars or telescopes will just narrow your field of view. Grab a deck chair or a warm blanket, prepare a hot drink, wrap up warm and lay out under the darkest conditions you can find. It’s an excellent activity to do alone or if you have children they’ll love an excuse to get outside for some after dark play.

Put away any lights or bright mobile phones and simply look up and wait. Remember it takes up to 30 minutes for your eyes to fully dark adapt and any exposure to bright lights will start the process all over again. If you need a light red touches are best for preserving you night vision.

For optimal viewing, head out after the Moon sets, or in the darkness of the pre dawn sky.

Approximate Moon set times at Highland latitudes this weekend:

Friday night 12.30am
Saturday night 1.30am

You can still see meteors with the moon up but generally only the brightest ones. Early morning viewing will be optimal as Leo (the radiant) is high in the sky then.

Good luck and clear skies!

Meteor_falling_courtesy_NASA

New Comet Alert!

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Look out for a new bright comet visible in night skies now and for the next couple of weeks.

Comet C/2017 O1 ASAS-SN is presently sweeping its way between the constellations Auriga (The Charioteer) and Perseus (The Hero). Later in Ocober it will move into the boundaries of the faint constellation Camelopardalis.

At magnitude 7 or 8 a good dark site and binoculars will be essential for viewing.

Right now at Highland latitudes, Perseus and Auriga start the evening about 20 degrees above the hoizon in the NE before rotating higher and higher in the sky towards the East beyond midnight. Viewing opportunities will therefore get better as the night progresses.

With a calculated orbital period of 17.000 years this will be a rare viewing opportunity.  Happy hunting.

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