Year
In astronomy, the Julian year is a unit of time; it is defined as 365.25 days of exactly 86,400 seconds (SI base unit), totalling exactly 31,557,600 seconds in the Julian astronomical year.
Bubnoff unit
The Bubnoff unit (abbreviated B) is a unit of speed equal to 1 m / 10 a. In other words, 1 B is equal to 1 meter in 1,000,000 years, 1 millimeter in 1,000 years, or one micrometer per year. It was defined in 1969.