PEDR – Precision Experiment Data Record
MOLA PEDR products can be searched specifically through the MOLA PEDR QUERY.
Instrument: Mars Orbiter Laser Altimeter
PDS Data Set ID: MGS-M-MOLA-3-PEDR-L1A-V1.0
The Mars Orbiter Laser Altimeter (MOLA) Precision Experiment Data Record (PEDR) data products contain instrument science data, spacecraft and sub-spacecraft location, estimates of the planetary radii, and radii of an aeroid equipotential surface. The MOLA topography is the shot planetary radius minus the aeroid radius at a given location.
Contained in a PEDR are the range value computed at the frame mid-point, the planetary radius at the frame mid-point, and the planetary radius for each shot. There are 20 possible shots in a 2 second frame, numbered from 1-20. Additionally, latitude, longitude, and radial distance, obtained from the precious orbit data, is stored in the PEDR. The precision orbit data is gathered at the frame mid-point with respect to the Mars Global Surveyor (MGS) center of mass. The range and planetary radius values are computed with respect to the center of mass of the MGS.
The change in latitude and longitude per frame is also stored, so that the location of individual shots may be obtained by interpolation via the generic formula:
shot_location = mid_pt_location + (shot_# - 10.5)/20 * delta_location
In view of the parallax introduced by off-nadir observations, there is an added first-order correction for deviations in radius from the frame mid-point radius to the location of each individual shot in a frame.
MOLA PEDR products have the following file names:
nnnnn = orbit number; for products from the Mapping Phase, this is the orbit number plus 10000
e = product edition number or letter
In ODE, PEDR products have the following product IDs: