4
$\begingroup$

This question here calculated the time a satellite was in the shadow of the earth for a circular orbit. I was wondering if there was a way to do the same thing for an elliptical orbit.

$\endgroup$

1 Answer 1

4
$\begingroup$

Only numerically

Yes, it is possible, but only with the use of numerical methods. Instead of using

$$ t = \tau \frac{\theta}{2\pi} $$

(As the answer you referenced does) You must use a more general expression derived from Kepler’s second law:

$$ dt = \tau \frac{r^2}{2\pi ab} d\theta $$

Where $\tau$ is the orbital period, $a$ and $b$ are the semi-major and semi-minor axis of the orbit, and $r$ is a function of $\theta$ the true anomaly. To solve for $t(\theta)$ requires numerical methods; there is no closed form solution except in the case of circular orbits.

$\endgroup$

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.