Convert Olympiads to Sidereal Years

Convert Olympiads (Ol) to Sidereal Years (a_sid) instantly and accurately.

Conversion Formula

a_sid = Ol × 3.999848183

About Olympiads

An Olympiad = exactly 4 Gregorian years = 1,461 days = 126,227,808 s. In ancient Greece it was the standard historical dating system counting from the first Olympic Games at Olympia in 776 BCE; adopted by Hellenistic historians (Polybius, Timaeus). Modern Olympiads are numbered from Athens 1896. The 4-year cycle is mirrored in US presidential elections and EU Parliamentary terms. 1 Ol = 4 yr = 126,227,808 s.

About Sidereal Years

The sidereal year = Earth's orbital period relative to the stars = 365.25636 days = 31,558,149.8 s - about 20 min 24 s longer than the tropical year. The gap arises from precession of the equinoxes (~50 arcsec/year westward drift), which causes the tropical year to end slightly before the sidereal orbit completes. JPL DE440 ephemerides and J2000.0 epoch are anchored to the sidereal frame. 1 a_sid = 365.25636 d.

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