Vis-Viva Equation
Calculate orbital speed and specific energy from the vis-viva equation.
Orbital velocity
8.60382 km/s
8,603.82 m/s
Specific energy
-19.93002 km2/s2
elliptic orbit
Vis-viva orbit state
Local orbital speed follows from the current radius and the orbit semi-major axis.
8.604 km/s
Orbital velocity
8.60382 km/s
8,603.82 m/s at the sampled radius
Specific energy
-19.93002 km2/s2
set by the semi-major axis
Geometry
r/a 0.700
7,000 km radius, 10,000 km semi-major axis
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