As a young lad, if there was one item in the night sky that drew me to astronomy, it was the moon.
The calculation of the moon's motion is one of the most difficult astronomical issues.
Ernest William Brown (1866–1938), an English mathematician and astronomer, spent his life studying the moon's motion and creating precise lunar tables.
A few of days following the new moon, we often see the moon for the first time as a delicately thin arc of light around a ghostly orb.
"The old moon in the new moon's arms" refers to the moon's night side being illuminated by Earth-reflected sunlight for nearly a week following new moon.
When the moon is low in the sky, season and latitude dictate the angle a line crossing the crescent moon's points or cusps creates with the horizon.
The crescent tilts left at mid-northern latitudes, as it will on February 21-22. Southernly, it's different.
When the moon is close to a bright star or planet, it may take only a few minutes to observe its eastward migration.