One of the definitions of crescent moon is βgrowing, increasing, or developing.β Several years ago, a reader wondered if saying βwaxing crescentβ with respect to the moon was redundant. However, the term crescent when applied to the moon usually means a curved sickle shape of either a waxing or waning (growing smaller) moon. A gibbous moon is one that is more than half lit.
Thursday, March 10, at 7 p.m. look to west to enjoy the 2-day-old crescent moon. The unlit portion of the moon will βglowβ from earthshine which is light reflected from the Earth cast onto the dark side of the Moon. By 8 p.m. the sky will be dark. Face south and look nearly overhead to see Gemini the Twins with the bright stars Castor (to the right and slightly farther north) and Pollux (to the left and slightly farther south).
Pollux is the 17th brightest star in the sky, and Castor is the 23rd brightest star in the sky. Castor is actually a six-star system consisting of three sets of double stars traveling through space together orbiting around each other in a complex fashion. Pollux is just as interesting as Castor. It has recently been discovered to have a giant planet orbiting it. Pollux is the brightest star currently known to have a planet. These twins deserve our enjoyment.
