Anomalistic Year
The perihelion is the point of closest approach between a planet and the Sun. The time at which a planet reaches perihelion provides a convenient measurement of the duration of the orbit. The anomalistic year is defined as the time between successive perihelion passages.
The time period between two perihelion passages is the anomalistic year.
Using the Earth as an example:
| Year | Duration (days) |
|---|---|
| Tropical year | 365.24219 |
| Sidereal period | 365.25636 |
| Anomalistic year | 365.25964 |
Study Astronomy Online at Swinburne University
All material is © Swinburne University of Technology except where indicated.