Full moon exact time, usually in Coordinated Universal Time (UTC). Typical monthly calendars that include lunar phases may be offset by one day when used in a different time zone. Full moon is generally a suboptimal time for astronomical observation of the Moon because shadows vanish. It is a poor time for other observations because the bright sunlight reflected by the Moon, amplified by the opposition surge, then outshines many stars. On 12 December 2008, the full moon occurred closer to the Earth than it had been at any time for the previous 15 years, called a supermoon. On 19 March 2011,
Equinox equinoxes shift through the constellations as follows (expressed in astronomical year numbering when the year 0 = 1 BC, −1 = 2 BC, etc.): The equinoxes are sometimes regarded as the start of spring and autumn. A number of traditional harvest festivals are celebrated on the date of the equinoxes. Observations of the equinox are frequently used in online debates between flat-earth conspiracy proponents and those who support the generally accepted heliocentric globe model. Wolfie6020, a well-known flat-earth debunker on YouTube, has a semi-annual Equinox Challenge with prizes available to any flat-earther who can show a functioning flat-earth model that