Data Set Overview : All PROFILE data are packaged by periapsis number for each aerobraking orbit. PROFILE data are provided at one second resolution in a table labeled Pyyy.tab where 'yyy' is the three digit periapsis number.   Parameters : Time from periapsis: Units : seconds Latitude: Units : degrees Longitude: Units : degrees Local Solar Time: Units : hours Solar Zenith Angle: Units : degrees Altitude: Units : km Density: Units : kg/km**3 Sigma density: Units : kg/km**3   Data : For each orbit, PROFILE data consist of an n-by-8 array in the file Pyyy, where n is the number of seconds of data received during the aerobraking pass. Column 1 contains the time from periapsis. Columns 2 through 8 contain Latitude, Longitude, Local Solar Time, Solar Zenith Angle, Altitude, Density, Sigma Density.   Processing : Accelerometer data were processed in the PROFILE stage through several steps and the entire process with examples is given in [TOLSONETAL2005] First, traditional Euler terms were removed body angular rates. During operations, no attempt was made to synchronize data or to remove the effects of thruster firings.   Coordinate System : Latitude and longitude are in the IAU Mars Centered Mars Equatorial System. Altitude is above the IAU reference ellipsoid, with a:3396 km and f:0.005206.

Confidence Level Overview : The standard deviation on density data consist of a noise term based on the rms residual outside the atmosphere and a 1% bias to account for instrument and aerodata base scale factors.   Review : Version 2 products are based on operational data sets which underwent orbit to orbit comparisons with navigation team and spacecraft team results, see TOLSONETAL2005.   Data Coverage and Quality : Data coverage during an aerobraking pass varied throughout the mission. The nominal pass assured that sufficient data were recovered above 250 km to calibrate the accelerometers both inbound and outbound.