Waning Crescent.
Waning crescent.
waning crescent
the waning gibbious
the waning gibbious
'Third Quarter' occurs 7.38 days after a Full Moon.After the Third Quarter, you'd have to wait 22.1 daysfor the next Full Moon.
The phase of the moon that occurs between the third quarter and the new moon is the waning crescent. During this phase, the illuminated part of the moon visible from Earth decreases until it eventually becomes a new moon with no visible illumination.
Third Quarter.
The Moon's third quarter phase, also known as the last quarter, occurs when half of the Moon's visible surface is illuminated and is located between the full moon and the new moon. The first quarter phase, conversely, also features half of the Moon illuminated but occurs between the new moon and the full moon. Both phases showcase the same amount of illumination (50% of the lunar surface), but they are opposite each other in the lunar cycle, with the first quarter appearing in the evening sky and the third quarter in the morning sky.
Third quarter moon is when the moon is halfway between full and new, while on the way to new. If you stand with your back to the sun, actually where the sun would be because its probably below the horizon, a third quarter moon will be about 90 degrees to your left, and the left face will be illuminated.
One-third .
In the year 2013 . . . -- The moon is not at Third Quarter on April 21. At 0000Z on 21 Apr, it's a waxing gibbous, about 74% illuminated. Its Right Ascension is then 09h 57m . -- The last Third Quarter before April 21 occurs on April 3 at 0500Z. RA is then 18h 57m . -- The next Third Quarter after April 21 occurs on May 2 at 1300Z. RA is then 20h 53m . (Times and RAs are rounded, which, I'm guessing, will be close enough for your purposes.)
The phase that occurs between the first quarter moon and the full moon is the waxing gibbous phase. During this phase, the illuminated portion of the moon continues to grow larger each night until it reaches full illumination.