Sunlit Design > The Sun API > Documentation > Time Values
- Introduction
+ Using the Functions
+ User Guide
+ Function Reference
+ Constants
Time Values
The Sun API's user functions support working with four timescales.All four timescales have the following in common:
- The basic unit of each is a day of 86,400 SI seconds.
- Whole numbers refer to a time at midnight and numbers ending in .5 refer to midday.
The four timescales are:
- Modified Julian Day (MJD) timescale
- Solar Day of Year (SDY) timescale
- Universal Time Day (UTD) timescale
- Clock Time Day (CTD) timescale
Each of the four timescales has a different purpose.