Convert Shakes to Tropical Years
Convert Shakes (sh) to Tropical Years (a_trop) instantly and accurately.
Conversion Formula
a_trop = sh × 3.168876540e-16
About Shakes
A shake = exactly 10 ns (10⁻⁸ s) - the informal unit for fission prompt-neutron generation time, coined at Los Alamos during the Manhattan Project (1943-1945). A prompt-neutron generation in a supercritical core takes ~1-10 shakes; a full explosive chain reaction unfolds over ~50-100 shakes. The name alludes to 'two shakes of a lamb's tail'. Still used in reactor physics and weapons-design calculations. 1 shake = 10 ns.
About Tropical Years
The tropical year = time from March equinox to the next = 365.24219 days = 31,556,925.2 s - the year that governs the seasons. The Gregorian 97/400 leap rule approximates it as 365.2425 days, leaving a residual drift of only ~26.8 s/year. The tropical year shortens ~0.53 s per century due to tidal deceleration. Persian Solar Hijri and Mayan Haab' calendars also approximate it. 1 a_trop ≈ 365.24219 d.
Quick Reference Table
| Shakes (sh) | Tropical Years (a_trop) |
|---|---|
| 1 sh | 3.169 × 10-16 a_trop |
| 2 sh | 6.338 × 10-16 a_trop |
| 5 sh | 1.584 × 10-15 a_trop |
| 10 sh | 3.169 × 10-15 a_trop |
| 25 sh | 7.922 × 10-15 a_trop |
| 50 sh | 1.584 × 10-14 a_trop |
| 100 sh | 3.169 × 10-14 a_trop |