Abstract: The current disclosure provides systems and methods of directly measuring angular velocity and angular acceleration of space objects and using the measured angular velocity and angular acceleration as inputs into new and unique algorithms for initial orbit determination. Sensors measuring locations and times of light events may be used to generate a virtual rate track image for identification of space objects. Right ascension and declination of the space object events versus time may be fit to polynomials or splines to determine associated angle, angular rate, and angular acceleration of the space objects. New and unique initial orbit algorithms may then be applied to estimate orbital elements of the space objects.

Abstract: The current disclosure provides systems and methods of directly measuring angular velocity and angular acceleration of space objects and using the measured angular velocity and angular acceleration as inputs into new and unique algorithms for initial orbit determination. Sensors measuring locations and times of light events may be used to generate a virtual rate track image for identification of space objects. Right ascension and declination of the space object events versus time may be fit to polynomials or splines to determine associated angle, angular rate, and angular acceleration of the space objects. New and unique initial orbit algorithms may then be applied to estimate orbital elements of the space objects.

Abstract: The current disclosure provides systems and methods of directly measuring angular velocity and angular acceleration of space objects and using the measured angular velocity and angular acceleration as inputs into new and unique algorithms for initial orbit determination. Sensors measuring locations and times of light events may be used to generate a virtual rate track image for identification of space objects. Right ascension and declination of the space object events versus time may be fit to polynomials or splines to determine associated angle, angular rate, and angular acceleration of the space objects. New and unique initial orbit algorithms may then be applied to estimate orbital elements of the space objects.

Abstract: Background-reducing x-ray multilayer mirror. A multiple-layer "wavetrap" deposited over the surface of a layered, synthetic-microstructure soft x-ray mirror optimized for reflectivity at chosen wavelengths is disclosed for reducing the reflectivity of undesired, longer wavelength incident radiation incident thereon. In three separate mirror designs employing an alternating molybdenum and silicon layered, mirrored structure overlaid by two layers of a molybdenum/silicon pair anti-reflection coating, reflectivities of near normal incidence 133, 171, and 186 .ANG. wavelengths have been optimized, while that at 304 .ANG. has been minimized. The optimization process involves the choice of materials, the composition of the layer/pairs as well as the number thereof, and the distance therebetween for the mirror, and the simultaneous choice of materials, the composition of the layer/pairs, and their number and distance for the "wavetrap.