The mathematics and orbit dynamics section in the control systems branch, spacecraft engineering department of the Naval Research Laboratory in Washington DC is seeking a recent PhD in aerospace engineering, physics, scientific computing or related area for an NRC Research Associateship. We are developing a method for propagation of distributions of orbits. The outcome will aid in orbit determination from highly uncertain observations or maneuvers, propagation of orbital debris, and the design and analysis of future space missions using large numbers of very small objects.

We have recently developed a technique to propagate the density of pieces from a simulated fragmentation, using what we call the "Lambert - Transformation of Variables" method. This method allows us to compute the spatial density exactly at any point from the velocity density at a single point (the fragmentation point). This research forms the basis for future work which will expand the computation to include perturbations and full six-dimensional phase space. Animations of the flow of density in the source orbital plane from a fragmentation in low-earth orbit are available on YouTube at https://goo.gl/fgvJ0Y, and a recent paper on the subject with more details is available at https://conference.sdo.esoc.esa.int/proceedings/sdc7/paper/346.

It is expected that the fruits of the research described will transition to operational application. The mathematics and orbit dynamics section has a long history and ongoing support for the US Space Surveillance Network. Other research currently conducted in the branch includes relative motion dynamics, spacecraft attitude control systems, space robotics, cognitive sensor processing, and rocket propulsion. We are seeking an Associate with excellent skills in mathematics, dynamics, and statistics, with applications to orbit dynamics and especially the expression of concepts from these fields as numerical algorithms, including programming.