The units of time are defined as follows. Unless otherwise stated, conversions refer to SI units.
A wink is defined as 1/3 nanosecond.
A shake is defined as 1e-8 second.
A svedberg is defined as 1e-13 second.
A blink is defined as 1e-5 day.

An SI minute is defined as 60 seconds.
An SI hour is defined as 60 minutes.
An SI day is defined as 24 hours.
A sidereal day, which varies daily, is approximately 23 hours, 56 minutes, and 4.1 seconds.
The sidereal hour, minute and second are defined as fractions of the sidereal day with factors of 1/24, 1/1440, and 1/8.64e4, respectively.

A standard pentad is defined as 5 days.
A standard week is defined as 7 days.
A standard fortnight is defined as 14 days.

The Month
A lunar month, which has also been called the lunation and synodic month, is approximately 29 days, 12 hours, 44 minutes, and 2.8 seconds.
A lune is defined as 1/30 lunar month.
A lunour is defined as 1/24 lunar day.
A nodical month, which has also been called the dracontic month, is approximately 27 days, 5 hours, 5 minutes, and 35.8 seconds.
An anomalistic month is approximately 27 days, 13 hours, 18 minutes, and 33.1 seconds.
A sidereal month is approximately 27 days, 7 hours, 43 minutes, and 11.6 seconds.
The Year
A standard year is defined as 365 days.
A leap year is defined as 366 days.
A sidereal year is approximately 365 days, 6 hours, 9 minutes, and 9.7632 seconds.
An ellipse year is approximately 365 days, 14 hours, 52 minutes, and 54.48 seconds.
A tropical year is approximately 365 days, 5 hours, 48 minutes, and 45.216 seconds.
An anomalistic year is approximately 365 days, 6 hours, 13 minutes, and 52.464 seconds.
The Julian calendar includes a leap year every fourth year. Therefore, a Julian year is defined as 365.25 days.
The Gregorian calendar includes a leap year every fourth year unless the year is a multiple of 100 and not a multiple of 400. Therefore, a Gregorian year is defined as 365.2425 days.
The proposed Orthodox calendar includes a leap year every fourth year, leaving out 7 leap years every 900 years. Therefore, a Orthodox year is defined as 366.2424222... days.
A galactic year is approximately 2.25e8 years.


hell if anybody cares... I was scouring maple help this morning and came across this thought it was interesting that they actually put a measurement with these

[Edited on November 14, 2007 at 9:08 AM. Reason : go ahead and put the rest of the stuff in]

11/14/2007 9:07:09 AM

interesting...

11/14/2007 9:10:51 AM

goFigure

11/14/2007 9:13:19 AM

11/14/2007 9:38:22 AM

svedberg is a cool word

11/14/2007 9:39:28 AM