GRAIL LGRS Experiment Data Record (EDR)
EDR – Experiment Data Record
Instrument: Lunar Gravity Ranging System
PDS Data Set ID: GRAIL-L-LGRS-2-EDR-V1DOI: 10.17189/1519558
For more information about LGRS products, see the Data Product SIS.
The Lunar Gravity Ranging System (LGRS) Experiment Data Record (EDR) data products are raw science data, originating from spacecraft telemetry, in time order with duplicates and transmission errors removed.
There are twelve product types in the LGRS EDR dataset.
|
Product |
Type |
Description |
|
DTC |
ASCII |
Time Correlation Data Record File (DRF) – clock correlation among real-time clock (RTC), base-time clock (BTC), and the 1-per-second pulse associated with LGRS time |
|
EHK |
ASCII |
Spacecraft Engineering Housekeeping data, including temperature sensor data for locations near the LGRS instrumentation |
|
LTB |
ASCII |
LGRS Time Bias of the LGRS in BTC time, accumulated list of biases over the complete mission, biases apply to the LGRS time tag of both spacecraft |
|
MAS |
ASCII |
Satellite Mass Data, accumulated list of center of mass and spacecraft mass over the complete mission |
|
S72 |
Binary |
Engineering Standard Format Data Units (SFDU) ID #72 |
|
S73 |
Binary |
Science SFDU ID #73 |
|
SAE |
ASCII |
Solar Array Eclipse data, including solar array short circuit currents and open circuit voltages, to identify eclipse events for spacecraft ephemeris models |
|
SCA |
ASCII |
Star Tracker Data, including attitudes from an on-board Kalman filter that processes Star Tracker attitude data and Inertial Measurement Unit (IMU) angular rotation data |
|
STC |
Binary |
Time Correlation SFDU |
|
TDE |
ASCII |
Measured time correlation between LGRS time and UTC, using Time Transfer System (TTS) S-band ranging collection DSS-24 |
|
THR |
ASCII |
Thruster Activation Data, including time tags, counts of cumulative work cycles for each thruster, recent thruster ‘on’ time, and cumulative thruster ‘on’ time |
|
WRS |
ASCII |
Wheel Rotation Speed data, including time tags, measures rotational wheel speed of each of four reaction wheels as determined by a digital tachometer |
LGRS EDR products have the following file names:
product00_yyyy_mm_dd_s_vv.xxx (with detached PDS labels for each file)
where:
product = product name from above
yyyy = year
mm = month
dd = day of month
s = GRAIL satellite identifier
A = GRAIL-A
B = GRAIL-B
X = combined product of GRAIL-A and GRAIL-B
vv = data product version number (starting from 00)
xxx = file extension
DAT = binary data table
ASC = ASCII data table
In ODE, EDR products have the following product IDs:
PRODUCT00_YYYY_MM_DD_S_VV.XXX