Archive for October 13, 2017

10/13/2017 – Ephemeris – The bright star Regulus dips behind the Moon Sunday morning

October 13, 2017 1 comment

Note:  The original program recorded for this day was erroneous in the timing and appearance of this event.  Occurring about an hour later than reported here.  The Interlochen personnel may or may not replace the original program with the one below.  Also those who downloaded the audio from before late Thursday night may have downloaded the incorrect mp3.

Ephemeris for Friday, October 13th. The Sun will rise at 7:55 a.m.. It’ll be up for 11 hours and 5 minutes, setting at 7:00 p.m. The Moon, 1 day past last quarter, will rise at 2:08 tomorrow morning.

On Sunday morning the Moon will pass in front of, or occult the bright star Regulus, the brightest star in Leo the lion. This will happen as morning twilight starts. Regulus will disappear at the left edge of the crescent Moon at around 5:47 a.m. A telescope or binoculars may be needed to spot Regulus. Go out at least 5 or 10 minutes early to make sure you can spot the star. Regulus will reemerge at 6:25 at the 11 o’clock position on the dark part of the Moon. Earth shine on the night side of the Moon may be bright enough to see its dark edge. Observers west of us in the United States except the northern most states west of Minnesota will also get a view. Those in specific locations in the northern tier of states will get to see Regulus just graze the north edge of the Moon.

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


Occultation start

Occultation of Regulus by the Moon disappearance at around 5:47 a.m. for northern Michigan. Created using Stellarium.

Occultation end

Occultation of Regulus by the Moon reappearance at around 6:25 a.m. for northern Michigan. Created using Stellarium.

Occultation Map

Map showing the locations where the occultation of Regulus will be visible. For the area bounded by heavy lines the occultation will occur at night. Click on image to enlarge. Credit: Occult4 by IOTA.