Convert Sidereal Years to Microcenturies
Convert Sidereal Years (a_sid) to Microcenturies (µcy) instantly and accurately.
Conversion Formula
µcy = a_sid × 10000.17421
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.
About Microcenturies
A microcentury (µcy) = 10⁻⁶ of a Julian century = 3,155.76 s ≈ 52 min 35.76 s. Popularised by Richard Feynman, who told audiences a one-hour lecture was 'approximately one microcentury'. An 87-minute film ≈ 1.65 microcenturies. No formal SI recognition, but a favourite pedagogical example of SI prefixes applied to large bases. 1 µcy = 3,155.76 s = 52.596 min.
Quick Reference Table
| Sidereal Years (a_sid) | Microcenturies (µcy) |
|---|---|
| 1 a_sid | 10000.2 µcy |
| 2 a_sid | 20000.3 µcy |
| 5 a_sid | 50000.9 µcy |
| 10 a_sid | 100002 µcy |
| 25 a_sid | 250004 µcy |
| 50 a_sid | 500009 µcy |
| 100 a_sid | 1000020 µcy |