Convert Weeks to Sidereal Years
Convert Weeks (wk) to Sidereal Years (a_sid) instantly and accurately.
Conversion Formula
a_sid = wk × 0.01916462164
About Weeks
A week (wk) = exactly 7 days = 604,800 s. The 7-day week derives from Babylonian astronomy assigning one of the seven classical celestial bodies to each day - preserved in English (Sun-day, Mon-day, Satur-day) and Romance language day names. It spread globally via Jewish, Christian, and Islamic calendars. ISO 8601 numbers weeks 1-52(53) with Monday as day 1. 365-day years contain 52 weeks + 1 day. 1 wk = 7 d = 604,800 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.
Quick Reference Table
| Weeks (wk) | Sidereal Years (a_sid) |
|---|---|
| 1 wk | 0.0191646 a_sid |
| 2 wk | 0.0383292 a_sid |
| 5 wk | 0.0958231 a_sid |
| 10 wk | 0.191646 a_sid |
| 25 wk | 0.479116 a_sid |
| 50 wk | 0.958231 a_sid |
| 100 wk | 1.91646 a_sid |