Editing Parabolic trajectory (section)

==Energy==
Under standard assumptions, the [[specific orbital energy]] (<math>\epsilon</math>) of a parabolic trajectory is zero, so the [[orbital energy conservation equation]] for this trajectory takes the form:
:<math>\epsilon = {v^2 \over 2} - {\mu \over r} = 0</math>
where:
*<math>v\,</math> is the orbital velocity of the orbiting body,
*<math>r\,</math> is the radial distance of the orbiting body from the [[central body]],
*<math>\mu\,</math> is the [[standard gravitational parameter]].

This is entirely equivalent to the [[characteristic energy]] (square of the speed at infinity) being 0:
:<math>C_3 = 0</math>