Q.

How do I convert angles from degrees, minutes and seconds to decimal degrees?

A.

Many sources of geographical coordinates give them in degrees, minutes and seconds. At the moment, you must manually convert them to decimal degrees. There are 60 minutes in a degree, and 60 seconds in a minute, so divide the number of minutes by 60 and add the result to the number of degrees, then divide the number of seconds by 3600 (60 times 60) and add this also. As an example, to convert the latitude 48° 15' 23" to decimal degrees, perform the calculation; Decimal degrees = 48 + 15/60 + 23/3600 = 48.25639 (rounded to 5 decimal places) Don't forget you need a minus sign also for latitudes south of the equator and longitudes west of Greenwich.

Developed and maintained by Chris Peat, Heavens-Above GmbH Please read the updated FAQ before sending e-mail.