Question 1

Why does the full moon rise at sunset?

Accepted Answer

A full moon sits opposite the sun in the sky, so it comes up in the east as the sun goes down in the west and stays up all night. Each night after, it rises about fifty minutes later — except near the Harvest Moon, when the shallow angle of its path makes the delay only twenty or thirty minutes for several evenings.

Question 2

Is the moon phase the same everywhere on Earth?

Accepted Answer

Yes — the phase is a fact about the moon and the sun, not about you. What changes with your place is the clock time of the instant, when the moon rises and sets, where it stands in your sky, and how its lit side is tilted.

Question 3

What is a supermoon?

Accepted Answer

A full moon that falls near perigee, the closest point of the moon's slightly oval orbit — closer than about 363,000 km by the rule the almanacs use. It looks about seven percent wider than an average full moon and up to fourteen percent wider than one at apogee; the difference is real, and hard to see without a comparison.

Waxing crescent tonight in Beijing, 17% lit. It rises at 10:12 AM in the east-south-east and sets at 8:05 PM.

Why the full moon rises at sunset

The phase is everyone's; the hour is yours

A supermoon, and a blue one