Guest Blogger Katrin Raynor-Evans visits Christmas in this festive episode!
Christmas is almost upon us and I am sure a few of us readers know well the names of Old Saint Nick’s eight reindeer. Comet perhaps being the most popular and memorable amongst us astronomers for obvious reasons. There are many stories behind their names but I think my favourite is that Comet is probably named so because comets ‘fly in the sky’ like the reindeers do.
One of my best-loved astronomical topics to research is comets and asteroids. I find them fascinating and having witnessed Halle-Bopp hanging in the sky like a beautiful otherworldly visitor from 1997-1998, the excitement and wonder of them has never left me. I was too young to know or remember Comet Halley and I am a bit annoyed with my Father for not remembering if he saw it or not!
On a Christmas-comet related topic, I couldn’t resist purchasing a comet-like Christmas decoration this year, which I think you will agree, represents Halley’s Comet well on a set of First Day Covers I have.
I was so excited to hear that we would be lucky enough to enjoy a Christmas comet this year, Comet 46P/ Wirtanen. Unfortunately I am yet to see Wirtanen because as luck would have it, the British weather has decided to just be grey and over cast for what feels like forever.
Comet Wirtanen may be new to some of us. So where did it come from and why can we see it so easily upon its return to our sky? The comet was first discovered in 1948 by Carl Wirtanen and is classed as a hyper active comet. This means that despite its small size, it emits a larger amount of water vapour than expected for its small size and spins every 8.9 hours (www.spaceweatherarchive.com). It is also classed within the Jupiter-family comets group. This means that is has an orbital period of less than 20 years and its orbit is determined by the gravitational influence of Jupiter.
It makes its closest approach to Earth, perihelion, a mere 7,220,000 miles away on the 16th December and some say that it will be visible to the naked eye. I suspect this will be the case if you are somewhere dark and away from light pollution for example the Brecon Beacons. Failing that, standing in the garden with a good pair of binoculars will do or if you have a telescope then even better. I will endeavour to try and see it from my back garden.
Comet Wirtanen can be located in the constellation of Taurus and is highest in the sky approximately around 10pm. If you can locate the asterism of the Pleiades then you are close to spotting Wirtanen as according to Astronomy Now (www.astronomynow.com), it is approximately 3¾ southeast of the constellation.
Don’t forget it’s not too late to purchase your Dark Sky Wales Gift vouchers for great Christmas Presents. They’re available here Dark Sky Wales
MERRY CHRISTMAS ALL AND A HAPPY NEW YEAR FROM ALL AT DARK SKY WALES!