Visibility of Comet Wirtanen

Forums Comets Comet 46P Wirtenan – visibility Visibility of Comet Wirtanen

Peter Anderson

Like many others I have not seen it. I tried several times in early December – I am 27.5deg South and 153 deg East, but did not see it and then the clouds rolled in. However, though in the hills, I live only 10km from the centre of a major city to my east and the sky is not dark. (At zenith mv 5.3 to 5.4 at best.)  I had simply tried in the area using binoculars and 8X50 finder scope and nothing ‘popped out’.  People well in the country- and here I am talking 200km away, saw it as a faint fuzz blob with a brighter core and shorter focus lenses recorded it as such.

Now, I am not a great fan of comets though there have been some spectacular ones. Ikeya Seki in 1965, Bennett in 1970, Halley maybe during the Total Lunar Eclipse on 24th April 1986, Hyakutake in 1996, and so on. Though it hung around for a while I wasn’t impressed by Hale-Bopp, though McNaught in January 2007 was great.  Now there were many others in this period, some I missed due to cloud, but no others ‘seared’ into my mind.

My experience in looking for comets is to deduct around 2 to 3 magnitudes from the stated brightness and then start looking, since much of the brightness is the fuzzy surrounding coma and a combined magnitude is the one given.

This is particularly so with comets approaching close to the Earth because, being closer the coma is so much more extended. IRAS Araki Alcock in 1983 as it travelled north to south in the evening sky, looked like a fuzzy ill defined tennis ball several degrees across – just a large fuzz blob with no discernable nucleus.  Very disappointing!

The diminutive but very active nucleus of Wirtanen only grew a narrow and faint tail but given the geometry (it was effectively at ‘opposition’ when closest), the tail would have been largely obscured by the fuzzy diffuse coma directly in front from our line of sight.

Anyway, for me, clouds again intervened around the time of closest approach. (You see our summer has much more rain and cloud.)
So I didn’t see Wirtanen either, but I don’t think I missed much.