CCSDS 508.0-R-1, Conjunction Data Message (Red Book, Issue 1 ...

DRAFT CCSDS RECOMMENDED STANDARD FOR CONJUNCTION DATA MESSAGESC5ADDITIONAL PARAMETERSAREA: The area of the object (m**2). The area could be defined by using a Radar CrossSection (RCS).CD_AREA_OVER_MASS: The perturbation of the object due to atmospheric drag(m**2/kg) used to propagate the state vector and covariance to TCA. Defined as C D •A/m,where C D is the drag coefficient, A is the area of the object, and m is the mass of the object.CR_AREA_OVER_MASS: The perturbation of the object due to solar radiation pressure(m**2/kg) used to propagate the state vector and covariance to TCA. Defined as C R •A/m,where C R is the solar radiation pressure coefficient, A is the area of the object and m is the massof the object.THRUST_ACCELERATION: The object’s acceleration due to in-track thrust (m/s**2)used to propagate the state vector and covariance of the object to TCA.SEDR (Specific Energy Dissipation Rate): The amount of energy (W/kg) being removedfrom a satellite’s orbit by atmospheric drag. It is a very useful metric for characterizingsatellites since it takes into account both the drag environment (atmospheric density) and the‘area to mass ratio’ of the specific object. It does this by including drag acceleration in thecomputation. Drag acceleration is proportional to atmospheric density and to satellite area tomass.SEDR is computed as follows:Instantaneous SEDR at time t is given by SEDR(t) A D Vwhere, = drag acceleration vector (inertial)ADV = velocity vector (inertial)Average SEDR over the orbit determination interval is given byt1SEDR(t)dtT 0where,CCSDS 508.0-R-1 Page C-5 March 2012