Abstract: In this paper we present three technical improvements that will better prepare satellites for their later removal prior to launch, in accordance with international agreements such as the IADC Space Debris Mitigation Guidelines, which ensure that satellites are designed to re-enter within 25 years. Space debris are non- functional satellites orbiting the Earth, such as abandoned second stage rockets, nanosatellites (most of which have no onboard propulsion) and collision fragments including those from deliberate destruction. Just-in-time Collision Avoidance (JCA) can prevent anticipated collisions. It requires far more precise orbit parameters for debris than we have now. The main tool we will use is ultra-precise laser ranging from an orbiting ranging station, which can operate up to 500 km range from a debris, provided it has good optical cross-sections. To enhance cross-sections, we would install 1-cm optical corner reflectors on each satellite, four around its equator and two at its poles so that one or more will always be visible. We compare pulsed and frequency-chirped CW lasers in this regard. To better optimize energetic efficiency of laser propulsion to nudge satellites away from a predicted collision, we suggest the Thomson scattering technique, which permits simultaneously measuring the change of target velocity and the plume exhaust velocity, which can be combined to calculate this efficiency in real time.
Keywords: Laser ranging, Just in time collision avoidance, Picosecond laser, Thomson scattering, Chirped-frequency CW laser.
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