This sheet includes answers to questions like, "How many minutes are in a month?" or "How many nanoseconds are in a dog year?"

It covers 58 different time measures, and the conversions are essentially exact (to 9 decimal places where needed).

Examples of small time units are: Becquerel wavelengths, femtoseconds, picoseconds, winks, and shakes.

Examples of large time units are: lifetimes, centuries, millenniums, Moon phases, Venus orbits, and Mars orbits.  (By the way, a lightyear is a distance, not a time span.)

This sheet does calculations based on nine (!) different years: tropical years, sidereal years, anomalistic years, ecliptic years, Gaussian years, Gregorian years, Julian years, civil years, and 365-day years.  That should stump even your best astronomer friends...

Enjoy!