How many seconds are there in a year?

myjoey

One year is equal to 31,558,152.96 seconds May 20 06, 9:17 AM

zbeckabee

31558152.96 http://experts.about.com/q/Astronomy-1360/Moon-orbit.htm May 20 06, 10:01 AM

acegregory

It depends on which definition of a year you want to use, there are at least 2 types of years: -Solar year (calendar) -Sidereal year (astronomical) A solar year is 365 days, 5 hr, 48 min, 46 sec of mean solar time (see solar time), which is the basis fot the Gregorian calendar. This comes to 31,556,926 seconds which is based on the earth relative to the sun and not the stars. This is the answer shown by Google calculator. Add about 1223 seconds to that for a sidereal year, which is closer to what the other replies show (Wikipedia shows several seconds less than the other replies at 31,558,149.54s and I'd go with that number since neither of the other answers here provides a valid source). The Sidereal year is based on the position of the earth relative to the stars other than our sun and is the measurement of a year preferred by astronomers for certain applications. See: http://en.wikipedia.org/wiki/Solar_year http://en.wikipedia.org/wiki/Sidereal_year http://www.bartleby.com/65/tr/tropyear.html http://www.astro.ufl.edu/~oliver/ast3722/lectures/CoordsNtime/time.htm Feb 26 09, 1:33 AM