Convert Julian Years to Seconds
Convert Julian Years (a_J) to Seconds (s) instantly and accurately.
Conversion Formula
s = a_J × 31557600
About Julian Years
The Julian year (a_J) = exactly 365.25 days = 31,557,600 s - the IAU standard year for astronomical distances. The light-year is formally 1 ly = c × 1 a_J = 9.461 × 10¹⁵ m (IAU 2012 B2). Julian years differ from Gregorian years by only 648 s (~10.8 min/year); important for high-precision astrometry or calculations spanning centuries. 1 a_J = 365.25 d = 31,557,600 s.
About Seconds
The second (s) is the SI base unit of time, defined since 1967 as exactly 9,192,631,770 periods of the caesium-133 ground-state hyperfine transition at 0 K. Caesium fountain clocks realise this to ~10⁻¹⁶ (1 s lost per ~300 million years); optical lattice clocks (Sr, Yb) reach ~10⁻¹⁸. The second links to the metre via the defined speed of light c = 299,792,458 m/s exactly. 1 s = 1,000 ms = 1/60 min.
Quick Reference Table
| Julian Years (a_J) | Seconds (s) |
|---|---|
| 1 a_J | 31557600 s |
| 2 a_J | 63115200 s |
| 5 a_J | 157788000 s |
| 10 a_J | 315576000 s |
| 25 a_J | 788940000 s |
| 50 a_J | 1.578 × 109 s |
| 100 a_J | 3.156 × 109 s |