Convert Millennia to Shakes
Convert Millennia (ka) to Shakes (sh) instantly and accurately.
Conversion Formula
sh = ka × 3.155695200e+18
About Millennia
A millennium (1 ka) = 1,000 Gregorian years ≈ 3.156 × 10¹⁰ s. Standard unit in archaeology and Quaternary geology: Neolithic transition ~10-12 ka BP; Last Glacial Maximum ~21 ka BP; Homo sapiens leaving Africa ~60-70 ka BP. Milankovitch cycles include the 41 ka obliquity and ~100 ka eccentricity cycle. EPICA Antarctic ice core spans ~800 ka. Precession completes ~26 ka. 1 ka = 1,000 yr.
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.
Quick Reference Table
| Millennia (ka) | Shakes (sh) |
|---|---|
| 1 ka | 3.156 × 1018 sh |
| 2 ka | 6.311 × 1018 sh |
| 5 ka | 1.578 × 1019 sh |
| 10 ka | 3.156 × 1019 sh |
| 25 ka | 7.889 × 1019 sh |
| 50 ka | 1.578 × 1020 sh |
| 100 ka | 3.156 × 1020 sh |