Convert Sidereal Days to Weeks
Convert Sidereal Days (sid.d) to Weeks (wk) instantly and accurately.
Conversion Formula
wk = sid.d × 0.1424670809
About Sidereal Days
A sidereal day = Earth's rotation period relative to the stars = 23 h 56 min 4.0905 s = 86,164.0905 s - ~3 min 56 s shorter than the 24 h solar day because Earth advances ~1° in its orbit each day. Equatorial telescope mounts rotate at one turn per sidereal day to track stars. VLBI, GPS orbit determination, and polar-motion monitoring use sidereal rotation as their reference. 1 sid. day = 86,164.0905 s.
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.
Quick Reference Table
| Sidereal Days (sid.d) | Weeks (wk) |
|---|---|
| 1 sid.d | 0.142467 wk |
| 2 sid.d | 0.284934 wk |
| 5 sid.d | 0.712335 wk |
| 10 sid.d | 1.42467 wk |
| 25 sid.d | 3.56168 wk |
| 50 sid.d | 7.12335 wk |
| 100 sid.d | 14.2467 wk |