Home > Ephemeris Program, The Moon > 12/18/2015 – Ephemeris – The Moon at first quarter tonight

12/18/2015 – Ephemeris – The Moon at first quarter tonight

December 18, 2015

Ephemeris for Friday, December 18th.  The Sun will rise at 8:15.  It’ll be up for 8 hours and 48 minutes, setting at 5:03.   The Moon, at first quarter today, will set at 1:17 tomorrow morning.

By the time we see the moon tonight it will be at least 8 hours since the Moon passed the first quarter point and it’s terminator or sunrise line will appear slightly bowed.   This time, since I can only point out a few features at a time, I’d like to point out three craters on the upper, north portion of the moon.  They may be too small for binoculars, but fine for small telescopes.  They make a nearly right triangle in Mare Imbrium, the Sea of Showers near the terminator.  The largest is Archimedes, named for the 3rd century BC Greek mathematician, and inventor.  The northern crater is Aristillus, named after a 3rd century BC astronomer, The other crater is Autolycus, named for a 4th century BC Greek astronomer.

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


First quarter Moon.

The first quarter Moon on December 18 at 9 p.m. EST. Highlighted are the trio of craters of which Archimedes is the largest. Created using Virtual Moon Atlas.

Other features visible are the crater Plato, the Alpine Valley, the crater Alphonsus, which I’ve covered in the past.  Search on them for their location and more information.


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