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A Low Cost Rendezvous Mission to 99942 Apophis

In recent years the public has become more aware of the potentially catastrophic consequences of an asteroid collision with Earth. Congress has taken note of this and instructed NASA to develop a program to determine the resources required to detect, track, characterize, and, if necessary, mitigate potentially hazardous objects. Characterization of an asteroid deemed sufficiently dangerous requires a space mission to determine its key attributes with sufficient accuracy to implement a mitigation scheme. Characterization mission designs to date have been based on the NASA Discovery mission model. This paper presents an approach for reducing the cost of NEO characterization missions by adapting low cost spacecraft and launch vehicle designs now in production by Orbital Sciences. Specifically, we show how the configuration of one of Orbital's small spacecraft designs coupled with a liquid propulsion system from an Orbital GEO communications spacecraft design is adapted to support delivery of a small science payload to the potentially hazardous near Earth asteroid 99942 Apophis. Using a C3 of less than 10 km2/s2, the Minotaur V low cost launch vehicle will place the spacecraft at Apophis in 321 days from a 2 May 2012 launch.