Convert Shakes to Gregorian Years
Convert Shakes (sh) to Gregorian Years (yr) instantly and accurately.
Conversion Formula
yr = sh × 3.168873851e-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 Gregorian Years
The Gregorian year = exactly 365.2425 days = 31,556,952 s (mean over the 400-year cycle with 97 leap years). The Julian calendar (45 BCE) used 365.25 days; Gregorian reform (1582) dropped 10 days and amended the centennial rule. Britain adopted it in 1752; Greece in 1923. Carbon-14 dates are reported in 'years BP' (before 1950 CE). 1 yr = 365.2425 d = 8,765.82 h = 31,556,952 s.
Quick Reference Table
| Shakes (sh) | Gregorian Years (yr) |
|---|---|
| 1 sh | 3.169 × 10-16 yr |
| 2 sh | 6.338 × 10-16 yr |
| 5 sh | 1.584 × 10-15 yr |
| 10 sh | 3.169 × 10-15 yr |
| 25 sh | 7.922 × 10-15 yr |
| 50 sh | 1.584 × 10-14 yr |
| 100 sh | 3.169 × 10-14 yr |