Convert Megayears to Shakes
Convert Megayears (Ma) to Shakes (sh) instantly and accurately.
Conversion Formula
sh = Ma × 3.155695200e+21
About Megayears
A megayear (1 Ma) = 10⁶ yr ≈ 3.156 × 10¹³ s - the timescale of geology and tectonic evolution. The K-Pg mass extinction at 66.0 Ma; Cambrian explosion ~538.8 Ma; Great Oxygenation Event ~2,400 Ma. Plate motion at 2-10 cm/yr = 200-1,000 km per Ma (Atlantic ~3,000 km wider since Pangaea rifting ~200 Ma ago). Background extinction rate measured in extinctions per million species-years. 1 Ma = 10⁶ 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
| Megayears (Ma) | Shakes (sh) |
|---|---|
| 1 Ma | 3.156 × 1021 sh |
| 2 Ma | 6.311 × 1021 sh |
| 5 Ma | 1.578 × 1022 sh |
| 10 Ma | 3.156 × 1022 sh |
| 25 Ma | 7.889 × 1022 sh |
| 50 Ma | 1.578 × 1023 sh |
| 100 Ma | 3.156 × 1023 sh |