What is the orientation of planetary orbits? I'm working on a planetary motion simulator. I've been working through the equations anomaly, eccentricity, etc. The one thing I'm curious about is if all the ellipses are oriented the exact same way (the direction of the periapsis of all planets are pointing the same way), or is it different for each planet?

What would this be called? I've only seen eccentricity and inclination.
No, the planet orbits do not have their major axis aligned.

http://en.wikipedia.org/wiki/Orbital_elements

You have Inclination and Longitude of the ascending node defining the plane, and Argument of periapsis defining the ellipse orientation in that plane.