That extra time known as a "sidereal" year must be accounted for somehow, the magazine says. Otherwise, seasons could be impacted. "If we didn’t account for this extra time, the seasons would ...

Slightly less than the 24 hours of a solar day (23 hours, 56 minutes, 4.1 seconds). Used in astronomy, sidereal means "when a star crosses the meridian" (the meridian is an imaginary circle around ...