LRO DIVINER Experiment Data Record (EDR)

EDR – Experiment Data Record

Instrument: Diviner Lunar Radar Experiment

PDS Data Set ID: LRO-L-DLRE-2-EDR-V1.0

For more information about Diviner EDR products, see the EDR Product SIS.

For more information about all Diviner products, see the Diviner Archive SIS.

Every 2.048 seconds the Diviner Lunar Radar Experiment collects a data “frame” containing the following:

  • 16 sets of science data, with each set containing 192 sixteen-bit science measurements from the focal plane interface electronics obtained over integration periods of 0.128 seconds

  • A single set of instrument engineering and housekeeping measurements (or “engineering data”)

Diviner software assembles the telemetry files into Experiment Data Record (EDR) data tables, each covering a one-hour time period.

Each Diviner EDR data product consists of two files. The first file is an ASCII formatted detached PDS label. The second file is the ASCII data table file. Each ASCII record contains 2656 bytes, and there is a record every 0.128 seconds (unless there is a data gap; time periods which contain no data do not produce data records).

While there is only a single set of engineering data for the 16 sets of science data, it is known during which of the 16 science data sets a given engineering measurement was taken. In the EDR, the engineering data are propagated across each science data set for a completely uniform and flat file. Each engineering measurement contains a valid value during the appropriate science data set, and the UNKNOWN_CONSTANT (-9999) during the other science data sets where engineering data were not obtained.

In the ASCII data tables, each complete set of science data plus engineering data is considered a “record”, and is contained on a single line. Where a data measurement is not valid or applicable, the UNKNOWN_CONSTANT will be found.

Diviner EDR products have the following file names:

yyyymmddhh_EDR.TAB (with detached PDS label)

where:

yyyymmdd = 8-digit date

hh = 2-digit hour. The hour represents the beginning of the one-hour period in which the data were taken.*

*Please note that some records may contain times that fall slightly outside of the one-hour range. This is due to the desire to keep all records that arrive in the same data frame together in the same file. Thus records may have a time of just before the hour given in the file name, or just after the end of said hour, to a maximum difference of 2.048 seconds.

In ODE, EDR products have the following product IDs:

YYYYMMDDHH_EDR.TAB