Just a year ago he reported in this magazine on the first successful determination of the

relative orbit of [this] famous double star....

Astrodynamics researchers propose a variable step numerical integration across eclipse boundary conditions for HAMR objects, equilibrium points for the perturbed rotating mass dipole, a set of

relative orbit elements for low-thrust control, and a longitudinal approach for station keeping of a GEO satellite.

Li, "

Relative orbit design and control of formation around displaced solar orbits," Aerospace Science and Technology, vol.

The relative position and velocity should be transformed to relative orbit root number during the optimizing process.

Alfriend, J2 Invariant Relative Orbits For Spacecraft Formations, Nasa Conference Publication, NASA, 1999.

For known masses, specifying the elements of the relative orbit and the positions and velocities of the center of mass is completely equivalent to specifying the positions and velocities of both bodies.

The relative orbit is then described mathematically as a hyperbola.

Yao, "

Relative orbit estimation and formation keeping control of satellite formations in low Earth orbits," Acta Astronautica, vol.

Moreover, we decide that the chaser is on a closed and inclined

relative orbit around the target.

In rigorous terms, the navigation problem becomes observable only in the presence of orbit control maneuvers, which change the

relative orbit geometry of the observation [11].

The linear combinations of eigenvectors, ([v.sub.1] + [[bar.v].sub.1]), ([v.sub.1] - [[bar.v].sub.1])([v.sub.2] + [[bar.v].sub.2]), ([v.sub.2] - [[bar.v].sub.2])i, ([v.sub.3] + [[bar.v].sub.3]), and ([v.sub.3] - [[bar.v].sub.3])i, are utilized to generate six different types of near-periodic

relative orbits with their periods of (2[pi]/[[theta].sub.1])[T.sub.d] and [T.sub.d], respectively.

Fighting Gravity and

Relative Orbits (Primo): Animator Joanna Priestley celebrates 20 years of her innovative filmmaking with two astounding collections, 16 shorts, four documentaries and a behind-the-scenes look at the award-winning artist and her work.