Convert Synodic Months to Shakes
Convert Synodic Months (syn.mo) to Shakes (sh) instantly and accurately.
Conversion Formula
sh = syn.mo × 255144287700000
About Synodic Months
A synodic (lunar) month = new moon to new moon = 29.5306 days = 2,551,442.9 s. Longer than the sidereal month (27.32 d) because Earth advances ~27° in its orbit during that time; the Moon must travel further to realign with the Sun. Islamic Hijri, Hebrew lunisolar, and Chinese calendars are built on synodic months. Eclipses repeat via the Saros cycle (18 yr 11 d = 223 synodic months). 1 syn.mo ≈ 29.5306 d.
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
| Synodic Months (syn.mo) | Shakes (sh) |
|---|---|
| 1 syn.mo | 2.551 × 1014 sh |
| 2 syn.mo | 5.103 × 1014 sh |
| 5 syn.mo | 1.276 × 1015 sh |
| 10 syn.mo | 2.551 × 1015 sh |
| 25 syn.mo | 6.379 × 1015 sh |
| 50 syn.mo | 1.276 × 1016 sh |
| 100 syn.mo | 2.551 × 1016 sh |