DESIGN OF A TAGGING MISSION TO NEAR EARTH ASTEROID 99942 APOPHIS

摘要

As the number of Near Earth Objects (NEOs) increases, so will the known risk from these objects of an Earth impact. Given current tracking capabilities, more precise trajectory information will be required to accurately determine any future potential impact. Such information could be obtained by sending a spacecraft to the object body along with a position relay technique such as a beacon, transponder or reflector. This examination presents a conceptual life cycle design for such an information relay mission. The target object for this study is Near Earth Asteroid (NEA) 99942 Apophis. Apophis is an approximately 260 meter diameter asteroid that is of current concern given its potential to impact the Earth in the year 2036 if it passes through a several hundred meter wide "keyhole" in the year 2029 (when it makes a close approach to the Earth). Apophis is taken as a test case for this mission design. The overall goal of the mission is provide sufficient information in order to decrease the size of the 2029 error ellipse so that if required, a deflection mission can be accomplished before the 2029 Apophis close encounter. It is assumed that enough data is returned to enable a deflection mission decision by 2017. A complete mission design (trajectory, mass, power, CAD, etc.) is presented for a small satellite mission to Apophis. Limited technology development is assumed for the spacecraft. Life cycle cost (technology/hardware development, acquisition, and operations) ad reliability assessments are also presented.