Archive for August 5, 2014

08/05/2014 – Ephemeris – The gibbous Moon and the Perseid meteors

August 5, 2014 Comments off

Ephemeris for Tuesday, August 5th.  The sun rises at 6:33.  It’ll be up for 14 hours and 29 minutes, setting at 9:02.   The moon, 2 days past first quarter, will set at 2:07 tomorrow morning.

As the moon moves around the Earth, its illuminated fraction gets greater since it’s now moving around to be opposite the sun in the sky which it will reach in 5 days, the full moon.  Tonight the face of the moon we see is 71 percent illuminated by the sun.  Anytime the moon is between 50 and 100 percent illuminated by the Sun we call a gibbous moon.  The word gibbous means hump-backed, and lets face it, the Moon looks cooler when it’s a crescent.  If you’re interested in the growing Perseid meteor shower and want to see it in dark skies, the hours of darkness will be restricted tonight to between moon set at 2:07 a.m. and the beginning of astronomical twilight at 4:32 a.m., though you can push it to 5 a.m. before the twilight becomes objectionable.

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


Gibbous Moon

The gibbous Moon tonight (August 5, 2014). Created using Virtual Moon Atlas.