[BAA-ebulletin 00769] Morning comets

[Rick]

[BAA-ebulletin 00769] Morning comets
(c) 2013 British Astronomical Association    http://www.britastro.org/

For those that don't mind getting up in the early hours there are four comets that can be seen in binoculars, although you will need large binoculars for three of them.

Best is 2013 R1 (Lovejoy) which has brightened rapidly and is now on the borders of naked eye visibility.  It is visible from about midnight onwards and is highest as dawn breaks.  At the moment the Beehive Cluster in Cancer makes a good starting point for sweeping towards the comet, which looks a bit like a globular cluster, but see the Computing Section webpages for good finder charts.  Those that don't like an early morning could wait until later in the month when it is at its brightest, but low in the sky below the Plough.

As previously explained 2012 S1 (ISON) never looked very likely to be the spectacular sight brighter than the full moon and visible in broad daylight that some pundits predicted.  In the event it has brightened even more slowly than my cautious predictions.  The nucleus appears to be smaller than the normal limit for surviving perihelion, so if you want to see the comet, now is probably the time.  From a darkish site it is visible in 20x80B, but is just a faint fuzzy patch.  A telescope may show the prominent tail that is visible in some of the excellent images that you can see in the Section image gallery.  Predicting its future brightness is a bit of a lottery, so keep an eye on the Section web page for the latest news, magnitude predictions for the bright comets are usually updated on Thursdays.

2P/Encke has a long history of observation, and this is one of the better returns for Northern Hemisphere observers.  It is beginning to drop into the dawn twilight, but can still be seen as a large fuzzy patch.  Images show a narrow gas tail.

Finally 2012 X1 (LINEAR) provided a surprise when it suddenly brightened by five magnitudes, in an outburst similar to those seen in 17P/Holmes and 29P/Schwassmann-Wachmann.  It was clearly a classical explosive outburst and images show the steadily expanding coma.  Although just visible in large binoculars, it will probably fade from view as the coma becomes more diffuse.

Observations of the above comets are welcome, particularly visual estimates of the total magnitude.  Details of the technique and format for reporting the observations is in the Section guide to observing comets, of which a new issue is in preparation.  As always, the Section web page is updated several times a week and will usually have the latest information on observable comets.

Jonathan Shanklin
Director, Comet Section