Bob Moler's Ephemeris Blog

Ephemeris for Monday, March 11th.  The sun will rise at 8:01.  It’ll be up for 11 hours and 42 minutes, setting at 7:43.  The moon is new today, and won’t be visible.

Comet PanSTARRS  is now officially in our skies.  It may be visible very low on the western horizon about 45 minutes after sunset.  That will make it about 8:30 p.m.  The head of the comet may make it to second magnitude, about as bright as a Big Dipper star.  The tail should point nearly straight up.  As the days go by the tail will lean to the right and the comet moves northward.  Tomorrow night the comet will be just left of the thin crescent moon.  Pictures of the comet can be found at spaceweather.com, from earlier this month.  PanSTARRS or Comet 2011 L4, as its official designation goes will probably not return.  It came in reasonably near the plane of the solar system, but is leaving far to the north.  Binoculars are the tool best used to spot it.

Times are for the Traverse City/Interlochen area of Michigan.  They may be different for your location.

Addendum

Comet PanSTARRS as it might appear above the western horizon at 45 minutes after sunset on March 11, 2013. Created using Stellarium and Cartes du Ciel.

Note that the comet will most likely not appear this bright.  At this time the comet is only 4 degrees above the horizon.  That’s less that half the width of a fist held at arms length above the horizon.  The comet will set in less than a half hour after that.

The reason for using images from Stellarium and Cartes du Ciel is that Stellarium does not show comet tails, and Cartes du Ciel does not try to show a realistic twilight.