Convert Sidereal Years to Attoseconds
Convert Sidereal Years (a_sid) to Attoseconds (as) instantly and accurately.
Conversion Formula
as = a_sid × 3.155814976e+25
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 Attoseconds
An attosecond (as) = 10⁻¹⁸ s - the timescale of electron dynamics in atoms. The Bohr-model orbital period in hydrogen is ~152 as. Electron tunnelling through atomic potential barriers takes a few hundred as. The 2023 Nobel Prize in Physics (Agostini, Krausz, L'Huillier) honoured methods for generating sub-100 as pulses via high-harmonic generation in Ti:sapphire lasers. 1 as = 10⁻¹⁸ s = 1,000 zs.
Quick Reference Table
| Sidereal Years (a_sid) | Attoseconds (as) |
|---|---|
| 1 a_sid | 3.156 × 1025 as |
| 2 a_sid | 6.312 × 1025 as |
| 5 a_sid | 1.578 × 1026 as |
| 10 a_sid | 3.156 × 1026 as |
| 25 a_sid | 7.89 × 1026 as |
| 50 a_sid | 1.578 × 1027 as |
| 100 a_sid | 3.156 × 1027 as |