Astrolabe is an easy to use calculator for manipulating astronomical dates & times, and coordinates, with many more capabilities coming soon.

Supported Date & Time Systems:

• Local civil time (LCT)
• Local Sidereal Time (LST)
• Greenwich Sidereal Time (GST)
• Universal Time (UT)
• Terrestrial Dynamical Time (TDT)
• Geocentric Coordinate Time (TCG)
• including Julian Date (JD), Modified Julian Date (MJD), and Truncated Julian Date (TJD)

Supported Coordinate Systems:

• Equatorial in Right Ascension (EQ(RA))
• Equatorial in Hour Angle (EQ(HA))
• Horizon (HOR)
• Ecliptic (ECL)
• Galactic (GAL)

Date & Time Features:

• Summary of time in all supported systems
• Calculation of time from an offset
• Conversion of time from one system to another with translation of location

Coordinate Features:

• Conversion of coordinates from one system to another

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