Saturday, March 2, 2013
Comets C/2011 L4 PanSTARRS and C/2012 F6 Lemmon 2-11 March
Comet PanSTARRS starts off around a hand-span and a half above the horizon about 3/4's of an hour after local sunset (that's roughly 8:30 in Adelaide, 6:50 in Brisbane etc.). Although comet PanSTARRS comes closer to the horizon each day, twilight also occurs earlier, so you should look somewhere between 3/4's of an hour to an an hour after local sunset each night, or possibly earlier. PanSTARRS is now visible to the unaided eye, with a magnitude of 2.8 being reported. You may try looking earlier.
The comet is quite small, with a star like nucleus and a short tail, you may find it easier to find the comet first in binoculars, then finding it with the unaided eye when you have located it in binoculars (update, based on tonight's reports it should be reasonably obvious, and well get better each night).
PanSTARRS will continue to get brighter over the next few days, being closest to the Earth on the 5th of March and closest to the Sun on the 10th. There are good prospects for it to get as bright as magnitude 1, which will make it quite visible in the twilight.
You will need a flat, unobstructed horizon like the ocean, or a high lookout or flat plains, to see the comet.
In contrast, comet Lemmon is around magnitude 5, and you will need to wait until astronomical twilight (an hour and a half after sunset), to see it, and then it is really only visible to the unaided eye in the countryside. It looks very nice in binoculars though. Those with decent cameras may wish to photograph the two comets together.
Printable PDF black and white maps suitable for field use are here (broad scale) and here (binoculars).
Here's a YouTube version of the animated GIF.