2017 January 15

Three decent comets on the way

Nick James

Three comets are likely to be a good prospects for observers in the UK over the next few months. They probably won’t be naked eye but they should be visible in binoculars from reasonably dark sites and they should be good for imagers.

45P/Honda-Mrkos-Pajdusakova

This comet has been a nice object but has been very difficult from the UK due to its southern declination and proximity to the Sun. Here is a selection of the some of the images in the Section archive:

http://www.britastro.org/cometobs/45p/45p_20170103_grhemann.html
http://www.britastro.org/cometobs/45p/45p_20170106_dpivato.html

I managed to capture this comet from the UK just after Christmas (image) but it was a very difficult object low in the evening twilight. It will become available from the UK in the morning sky early in February rising out of the dawn over the first couple of weeks of the month as it approaches the Earth. It is expected to be around 7th magnitude with an ion tail a few degrees in length and so should be a good target for imagers. On the 3rd it will be around 10 deg above the horizon at 6am as the sky is starting to brighten. The full Moon comes comes along on the 11th which is the day that 45P is at its closest to us. On that day the comet comes with 0.1 au of the Earth and it will be racing through Hercules at 22 arcsec/min. The penumbral lunar eclipse reaches a maximum at 01:10 UT on the 11th. This will dim the Moon somewhat and so may help with imaging the comet as it rises that morning.

A chart (courtesy Megastar/Don Miles) showing the comet’s path from now until February 11 is here.

C/2015 V2 (Johnson)

This is quite a nice looking comet which is very well placed for observation from the UK at the moment.

http://www.britastro.org/cometobs/2015v2/2015v2_20170102_0451_pcarson.html

The comet is currently around 12th mag but it should continue to brighten through the spring getting to 8th mag in April, still well placed. By the summer it might 6th mag although it will be much more difficult to see then.

41P/Tuttle-Giacobini-Kresak

This comet is currently around 16th mag but it should brighten quickly possibly becoming naked eye in April. It will be very well placed in northern Hercules in mid April, not that far from C/2015 V2. In fact these two reasonably bright comets would be good targets at the BAA Winchester Meeting (although that is a bit close to full moon).

http://www.britastro.org/cometobs/41p/41p_20170110_0015_pcarson.html