Ground magnetometer data have been providing important knowledge of magnetic pulsations (or ULF waves) for more than a hundred years. With the advance of modern technologies, the accuracy of measurements is constantly improving. In addition, more arrays of magnetometer stations have been established. However, the usage of magnetometer arrays for studying magnetic pulsations has not been fully e...

Power beaming from ground-based systems to space-based platforms has been proposed by a number of researchers as a means of delivering energy to orbiting satellites and stations. This paper considers the use of a seeded high-gain highefficiency Free-Electron Laser (FEL) amplifier based on a conventional linac as the source for power beaming. While the wall-plug efficiency of a single pass FEL i...

Scheduling of contacts between several satellites and ground stations has been historically sub-optimally approached. This fact raises the question: can this problem be solved in polynomial time? Although existing literature provided optimal solutions for some simplified versions of this problem and studied some connections with general scheduling, fewhas been said on the complexity ofmore gene...

There is an increasing desire in many organizations, including NASA and the DoD, to use constellations or fleets of autonomous spacecraft working together to accomplish complex mission objectives. At the Air Force Research Laboratory’s (AFRL) Space Vehicles Directorate we are investigating and developing architectures for commanding and controlling a cluster of cooperating satellites. For many ...

suspended aerosols in the atmosphere have strong impact on the global climate. they influence the earth’s radiation budget by scattering or absorbing both incoming and outgoing radiation. aerosols in troposphere are caused by natural sources, such as dust, sea-spray and volcanoes and also by anthropogenic sources, such as combustion of fossil fuels and biomass burning activities and from gas-to...