Our calendar has leap years because
A)there is one more sidereal day in a year than solar days.
B)a tropical year is slightly more than 365 days.
C)there is a difference between a sidereal year and a tropical year.
D)the perihelion of Earth's orbit is slowly advancing.

Question

Quizplus · Accepted Answer

A tropical year, which is based on the Earth's orbit around the sun, is slightly longer than 365 days. To keep the calendar year in sync with the tropical year, an extra day (leap day) is added to the calendar every four years.

Our Calendar Has Leap Years Because