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I'm trying to compute Mean Anomoly. Mean Anomoly is an angle that describes where in an orbit an object is relative to its periapsis. The formula according to Wikipedia is
[tex]
M = E - e \cdot \sin E
[/tex]
where e is eccentricity (which I know), and E is Eccentric Anomoly.
According to Wikipedia, Eccentric Anomoly is
[tex]
E = \arccos \frac{{1 - \left| r \right|/a}}{e}
[/tex]
where a is Semi-Major Axis (which I know), e is eccentricity (which I know), and r is an orbiting body's position vector. If I solve for r, I'm home free.
According to Wikipedia, The orbital position vector r is a cartesian vector describing the position of the orbiting body. Wouldn't that mean that r would be express as something like 1.0i + 2.0j+3.0k? But I can't plug something like that into the formula for Eccentric Anomoly. I could use Pothagorean Theorum to solve for distance and use this number. But that turns the vector into a scalar, and I doubt that's the right way to do it. Direction is pretty important here.
I know the object's x, y, and z position wrt the reference frame. How do I turn r into something I can use in these formulas?
[tex]
M = E - e \cdot \sin E
[/tex]
where e is eccentricity (which I know), and E is Eccentric Anomoly.
According to Wikipedia, Eccentric Anomoly is
[tex]
E = \arccos \frac{{1 - \left| r \right|/a}}{e}
[/tex]
where a is Semi-Major Axis (which I know), e is eccentricity (which I know), and r is an orbiting body's position vector. If I solve for r, I'm home free.
According to Wikipedia, The orbital position vector r is a cartesian vector describing the position of the orbiting body. Wouldn't that mean that r would be express as something like 1.0i + 2.0j+3.0k? But I can't plug something like that into the formula for Eccentric Anomoly. I could use Pothagorean Theorum to solve for distance and use this number. But that turns the vector into a scalar, and I doubt that's the right way to do it. Direction is pretty important here.
I know the object's x, y, and z position wrt the reference frame. How do I turn r into something I can use in these formulas?