1 Julian Date Calculator
Enter a date and time.
2 Sidereal-Time Calculator
Calculates GMST and local sidereal time.
3 Moon-Phase Calculator
Enter a date and time.
4 Sunrise / Sunset Calculator
Uses NOAA-style solar equations.
5 Solar Elevation / Azimuth
Enter location and local time.
6 Great-Circle Distance
Uses a spherical Earth approximation.
7 Orbital-Period Calculator
Circular orbit period.
8 Escape-Velocity Calculator
Escape velocity at selected altitude.
9 Satellite Orbital Speed
Circular-orbit speed.
10 TLE Epoch / Age Calculator
Reads the YYDDD.DDDDDDDD epoch field from TLE line 1.
11 Solar / Lunar Eclipse Calculator
Next-eclipse predictions will appear here.
Choose the number/type of total eclipses, then click “Find Next X Total Eclipses Visible Here”.
Select a city or enter latitude/longitude, choose a year, then search.
Precision solar-eclipse engine: checking…
General eclipse estimates use the built-in calculator. Total-solar-eclipse searches use Astronomy Engine's higher-precision local eclipse routines.
12 Radio Horizon Calculator
Estimates line-of-sight radio horizon.