03/18/2013 – Ephemeris – Comet PanSTARRS, the view from Stereo B
Ephemeris for Monday, March 18th. The sun will rise at 7:48. It’ll be up for 12 hours and 3 minutes, setting at 7:52. The moon, 1 day before first quarter, will set at 2:54 tomorrow morning.
Comet PanSTARRS is now a prominent part of our twilight after sunset. It should be visible from maybe 8:40 until 9:41 p.m. when it sets, clear skies and a low horizon willing. Photographs are coming in from all over, including a time lapse movie from the satellite Stereo B, which is now nearly behind the sun looking back at the comet and the earth in the background. The dust tail of the comet was being ejected in sheets, possibly due to the rotation of the comet’s nucleus. Comets generally eject gas and dust from one of more hot spots. When rotated toward the sun they become active and begin to spew gas and dust. When rotated away, they become quiet once again. It looks like Comet PanSTARRS is matching its original brightness estimates.
Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
The video from Stereo B can be found here:
and here:
http://stereo.gsfc.nasa.gov/gallery/item.php?id=selects&iid=182
Comet PanSTARRS in the next 5 days at 9:15 p.m. Created using Stellarium and Cartes du Ciel.
Bob Moler's Ephemeris Blog 