Below are definitions for the limited selection of keywords from the PDS labels which are shown on each of the browse image pages.

Accumulation Count

Identifies the number of start/stop temperature readings found in the APXS data.

APXS Mechanism Angle

APXS mechanism angle, measured in degrees at STOP_TIME. This value is derived from the raw data value returned in the APXS Results as part of the spectrum data. The value is derived by subtracting 112.64 from the product of the raw value multiplied by 1.28.

derived value = (raw value x 1.28) - 112.64

Command Sequence Number

Provides a numeric identifier for a sequence of commands sent to a spacecraft or instrument.

Contact Sensor State

The state of the APXS contact sensor at STOP_TIME as returned in the APXS Results as part of the spectrum data packet. Contact sensors are located on various portions of the Rover and APXS instrument. Contact sensor bits are as follows:

bit 0: right front solar panel
bit 1: left front solar panel
bit 2: left rear solar panel
bit 3: right rear solar panel
bit 4: right front bumper
bit 6: left front bumper
bit 8: lower APXS contact sensor
bit 9: starboard APXS contact sensor
bit 10: port APXS contact sensor
bit 15: unknown, received an interrupt, no latch set

Bit 0 is the least significant bit, Bit 15 is the most significant bit.

Dark Current Correction Type

The type of dark current correction applied to the image. Valid values are: PRIME = vertical for the front rover cameras, horizontal for the back camera; BOTH = both horizontal and vertical. See RVCMDRDS.CAT for further details.

Dark Level Correction

The dark level correction value subtracted from every pixel in the red plane. See RVCMDRDS.CAT for further details. (This is an array of three values in the data product labels, but three separate values in the index tables.)

Expected Packets

The total number of telemetry packets which constitute a complete data product, i.e., a data product without missing data.

Exposure Duration

The time interval between the opening and closing of an instrument aperture. The IMP camera does not have a shutter in the traditional sense, so for MPF this value is the integration time for manual and auto exposure, measured in milliseconds.

Exposure Type

Indicates the exposure setting on a camera. For the rover cameras, the valid values are: AUTO, INCR (incremental), MANUAL, PRETMD (pretimed), and NONE. AUTO exposure automatically adjusts the exposure time by iterating off of a pre-set exposure time. INCR exposure also automatically adjusts the exposure time, but iterates off of the exposure time from the previous image. MANUAL exposure is a single exposure with a set exposure time. PRETMD exposure uses the last exposure time used, regardless of the type of exposure it was. NONE indicates that the command moves only the camera and doesn't take an exposure.

Image Time

Date and time at which the image was acquired, recorded in UTC system format. Shown as: "YYYY-MM-DDThh:mm:ss.fffZ".

Instrument Name

Provides the full name of an instrument. Note: that the associated instrument_id element provides an abbreviated name or acronym for the instrument. Example values: FLUXGATE MAGNETOMETER, NEAR_INFRARED MAPPING SPECTROMETER.

Instrument Temperature

Provides the temperature, in degrees Celsius, of an instrument or some part of an instrument.

For the APXS data, this is the temperature of the electronics box at the alpha pre-amplifier at the beginning and end of each accumulation cycle. There will be at most 10 pairs. Measured in degrees centigrade.

Degrees = (<raw counts> x 1.5541) - 273.6

Instrument Compression Blocks

Provides the number of blocks used to spatially segment a data product prior to compression.

Instrument Compression Name

Identifies the type of on-board compression used for data storage and transmission. Note: The inst_cmprs_mode element provides an abbreviated identifier for the inst_cmprs_name.

Linear Accelerometer

X and Y readings for linear accelerometers on the Rover at STOP_TIME. X indicates pitch, where positive values indicate Rover front is lower; Y indicates roll, where positive values indicating right side is lower. Values are the raw counts from the telemetry. The conversion factor to have this value in units of 'g' is 0.0009765.

MPF Local Time

Local time at the lander site on the surface of Mars, measured in local hours, minutes, and seconds, from midnight. Local hours are defined as one twenty-fourth of a local solar day. Local minutes are one sixtieth of a local hour, and local seconds are one sixtieth of a local minute. Format is "hh:mm:ss".

Observation Name

The purpose of an observation or sequence of commands.

Packet Creation SCLK

SCLK from the primary telemetry packet header of the 1st packet of the image. Used for requesting image packets from TDS.

Planet Day Number

The Martian day (ie., sidereal day, equal to a rotation of 360 degrees) on which the image was taken. Starts with 1 as the first day of surface operations, the day the spacecraft landed. Negative values refer to pre-surface images.

Product Id

Represents a permanent, unique identifier assigned to a data product by its producer. Note: In the PDS, the value assigned to product_id must be unique within its data set.

Received Packets

Provides the total number of telemetry packets which constitute a reconstructed data product.

Rover Heading

Angular measure clockwise from Lander north in BAMS (Binary Angle Measurement, where 2¹⁶ BAMS equals one revolution).

Rover Position

X and Y offsets in meters north and east, respectively, of the Lander reference. (This is a two element array in data object labels, but two separate values in index tables.)

Sampling Duration

Spectrum accumulation time as returned in the first two bytes of the spectrum data.

Solar Azimuth

One of two angular measurements indicating the position of the Sun as measured from the lander. The azimuth is measured positively in the clockwise direction (as viewed from above) with the meridian passing through the positive spin axis of the planet (ie., the north pole) defining the zero reference.

Solar Elevation

One of two angular measurements indicating the position of the Sun as measured from the lander. The elevation is measured up from the plan which is perpendicular to the line passing between the lander and the center of Mars and which intersects the lander.

Spacecraft Clock Start Count

Provides the value of the spacecraft clock at the beginning of a time period of interest.

Spacecraft Clock Stop Count

Provides the value of the spacecraft clock at the end of a time period of interest. Note: for the Rover Camera MIDRs, this is the SPACECRAFT_CLOCK_START_COUNT from the latest acquired EDR used as input to a mosaic.

Start Time

Provides the date and time of the beginning of an event or observation (whether it be a spacecraft, ground-based, or system event) in UTC system format. Formation rule: YYYY-MM-DDThh:mm:ss[.fff]

Stop Time

Provides the date and time of the end of an observation or event (whether it be a spacecraft, ground-based, or system event) in UTC system format. Formation rule: YYYY-MM-DDThh:mm:ss[.fff]