Choose an Orbit Around a Schwarzschild Black Hole

You can see for yourself how a photon moves around a black hole. You will have to choose where the photon starts, and also on which initial direction it moves.
Everything is measured in gravitational radii. The 'viewport' is currently set to [-10,10]x[-5.2,10].

Please enter the values describing the starting point of the photon using the fields below, in polar coordinates.

• starting radius . This is the distance to the black hole, measured in gravitational radii, at which the photon starts its movement.
• polar angle of the starting point, measured anti-clockwise in degrees. A value of 0 means that the photon starts on the Ox axis.
• starting angle of the photon. Measured with respect to the Ox axis, in degrees. A value of 90 means straight up.

Starting radius (r)
Polar angle of the starting point (phi, in deg)
Starting angle of photon (theta, deg)