PDS_VERSION_ID = PDS3
RECORD_TYPE = FIXED_LENGTH
RECORD_BYTES = 280
FILE_RECORDS = 5600
^TABLE = "812506AA.OCS"
INSTRUMENT_HOST_NAME = "MARS GLOBAL SURVEYOR"
TARGET_NAME = "MARS"
INSTRUMENT_NAME = "RADIO SCIENCE SUBSYSTEM"
DATA_SET_ID = "MGS-M-RSS-5-EDS-V1.0"
PRODUCT_ID = "812506AA.OCS"
PRODUCT_RELEASE_DATE = 2007-09-30
DESCRIPTION = "The EDS occultation summary (OCS) file
contains the header records from each ionospheric electron density
(EDS) file created by the Radio Science Team (RST) during the Mars
Global Surveyor (MGS) mission. Information in the file includes:
start and stop time of the data collection
UTC and local true solar time of the occultation
latitude, longitude, and solar zenith angle of the occultation
names of files used in the processing
The individual header records are supplemented by the EDS file
name, which has been added at the end of each row.
This file was created by D.P. Hinson of the MGS RST at Stanford
University."
START_TIME = 1998-12-24T03:47:00
STOP_TIME = 2005-06-09T23:52:00
SOFTWARE_NAME = "N/A"
PRODUCT_CREATION_TIME = 2007-09-27T22:30:00
PRODUCER_ID = "MGS RST"
OBJECT = TABLE
ROWS = 5600
COLUMNS = 26
ROW_BYTES = 280
INTERCHANGE_FORMAT = ASCII
DESCRIPTION = "The table has 5600 rows. Each row has 26
columns (a total of 278 data bytes) followed by an ASCII carriage-
return line-feed pair in positions 279 and 280."
OBJECT = COLUMN
NAME = "START TIME"
COLUMN_NUMBER = 1
DATA_TYPE = TIME
START_BYTE = 1
BYTES = 23
UNIT = "N/A"
DESCRIPTION = "The Earth Receive Time at which
the first radio occultation data sample was acquired."
END_OBJECT = COLUMN
OBJECT = COLUMN
NAME = "STOP TIME"
COLUMN_NUMBER = 2
DATA_TYPE = TIME
START_BYTE = 25
BYTES = 23
UNIT = "N/A"
DESCRIPTION = "The Earth Receive Time at which
the last radio occultation data sample was acquired."
END_OBJECT = COLUMN
OBJECT = COLUMN
NAME = "OCCULTATION TIME"
COLUMN_NUMBER = 3
DATA_TYPE = TIME
START_BYTE = 49
BYTES = 23
UNIT = "N/A"
DESCRIPTION = "The time at Mars when the
experiment was sounding the ionosphere at 130 km altitude.
This is computed by subtracting the Mars-to-Earth light time
from the appropriate Earth Receive Time."
END_OBJECT = COLUMN
OBJECT = COLUMN
NAME = "ORBIT NUMBER"
COLUMN_NUMBER = 4
DATA_TYPE = ASCII_INTEGER
START_BYTE = 73
BYTES = 5
FORMAT = "I5"
UNIT = "N/A"
DESCRIPTION = "Orbit number from which the data
were acquired; set to zero if not known."
END_OBJECT = COLUMN
OBJECT = COLUMN
NAME = "DSN ANTENNA NUMBER"
COLUMN_NUMBER = 5
DATA_TYPE = ASCII_INTEGER
START_BYTE = 79
BYTES = 2
FORMAT = "I2"
UNIT = "N/A"
DESCRIPTION = "Number of the DSN antenna used
to collect the data (e.g., 14, 43, 65, ...)."
END_OBJECT = COLUMN
OBJECT = COLUMN
NAME = "RAY PATH DIRECTION"
COLUMN_NUMBER = 6
DATA_TYPE = ASCII_REAL
START_BYTE = 82
BYTES = 6
FORMAT = "F6.1"
UNIT = "DEGREE"
DESCRIPTION = "The angle between local north and
the direction of radio signal propagation at the point of
closest approach to Mars. Angle is measured positive from
local north toward local east. A signal traveling from west
toward east would have a ray-path-direction of 90 degrees."
END_OBJECT = COLUMN
OBJECT = COLUMN
NAME = "ANGLE FROM DIAMETRIC"
COLUMN_NUMBER = 7
DATA_TYPE = ASCII_REAL
START_BYTE = 89
BYTES = 6
FORMAT = "F6.1"
UNIT = "DEGREE"
DESCRIPTION = "Angle at which the spacecraft
rises or sets behind the planet limb, measured clockwise from
the planet radial direction as viewed from Earth. An angle-
from-diametric equal to zero indicates a diametric occultation
with motion of the ray away from the surface (e.g., occultation
egress). A value near 180 degrees is a nearly diametric ingress
occultation."
END_OBJECT = COLUMN
OBJECT = COLUMN
NAME = "LATITUDE OF PROFILE"
COLUMN_NUMBER = 8
DATA_TYPE = ASCII_REAL
START_BYTE = 96
BYTES = 7
FORMAT = "F7.3"
UNIT = "DEGREE"
DESCRIPTION = "Areocentric (north) latitude
where the experiment sounded the ionosphere at 130 km altitude."
END_OBJECT = COLUMN
OBJECT = COLUMN
NAME = "SIGMA LATITUDE"
COLUMN_NUMBER = 9
DATA_TYPE = ASCII_REAL
START_BYTE = 104
BYTES = 6
FORMAT = "F6.3"
UNIT = "DEGREE"
DESCRIPTION = "One standard deviation uncertainty
in LATITUDE OF PROFILE. This value also serves as an estimate
of the uncertainty in LATITUDE in RSED_TABLE. Set to -9.999 if
not known."
END_OBJECT = COLUMN
OBJECT = COLUMN
NAME = "LONGITUDE OF PROFILE"
COLUMN_NUMBER = 10
DATA_TYPE = ASCII_REAL
START_BYTE = 111
BYTES = 8
FORMAT = "F8.3"
UNIT = "DEGREE"
POSITIVE_LONGITUDE_DIRECTION = "EAST"
DESCRIPTION = "Areocentric east longitude where
the experiment sounded the ionosphere at 130 km altitude."
END_OBJECT = COLUMN
OBJECT = COLUMN
NAME = "SIGMA LONGITUDE"
COLUMN_NUMBER = 11
DATA_TYPE = ASCII_REAL
START_BYTE = 120
BYTES = 6
FORMAT = "F6.3"
UNIT = "DEGREE"
DESCRIPTION = "One standard deviation uncertainty
in LONGITUDE OF PROFILE. This value also serves as an estimate
of the uncertainty in LONGITUDE in RSED_TABLE. Set to -9.999 if
not known."
END_OBJECT = COLUMN
OBJECT = COLUMN
NAME = "SUB-SOLAR LATITUDE"
COLUMN_NUMBER = 12
DATA_TYPE = ASCII_REAL
START_BYTE = 127
BYTES = 6
FORMAT = "F6.2"
UNIT = "DEGREE"
DESCRIPTION = "Areocentric (north) latitude of
the sun at OCCULTATION TIME."
END_OBJECT = COLUMN
OBJECT = COLUMN
NAME = "SUB-SOLAR LONGITUDE"
COLUMN_NUMBER = 13
DATA_TYPE = ASCII_REAL
START_BYTE = 134
BYTES = 7
FORMAT = "F7.2"
UNIT = "DEGREE"
POSITIVE_LONGITUDE_DIRECTION = "EAST"
DESCRIPTION = "Areocentric east longitude of the
sun in body fixed coordinates at OCCULTATION TIME."
END_OBJECT = COLUMN
OBJECT = COLUMN
NAME = "SOLAR LONGITUDE"
COLUMN_NUMBER = 14
DATA_TYPE = ASCII_REAL
START_BYTE = 142
BYTES = 6
FORMAT = "F6.2"
UNIT = "DEGREE"
DESCRIPTION = "Value of the angle between the
Mars-Sun line at OCCULTATION TIME and the Mars-Sun line at the
Mars vernal equinox. Measured positive with increasing time
following the vernal equinox. Sometimes denoted L-sub-s."
END_OBJECT = COLUMN
OBJECT = COLUMN
NAME = "SPACECRAFT TO LIMB DISTANCE"
COLUMN_NUMBER = 15
DATA_TYPE = ASCII_REAL
START_BYTE = 149
BYTES = 9
FORMAT = "E9.3"
UNIT = "METER"
DESCRIPTION = "Distance along ray path from
spacecraft to point of closest approach to Mars. Measured
at time when experiment was sounding the ionosphere at 130 km
altitude."
END_OBJECT = COLUMN
OBJECT = COLUMN
NAME = "SPACECRAFT TO DSN DISTANCE"
COLUMN_NUMBER = 16
DATA_TYPE = ASCII_REAL
START_BYTE = 159
BYTES = 9
FORMAT = "E9.3"
UNIT = "METER"
DESCRIPTION = "Distance from spacecraft to DSN
receiving antenna at time when experiment was sounding the
ionosphere at 130 km altitude."
END_OBJECT = COLUMN
OBJECT = COLUMN
NAME = "MARS TO SUN DISTANCE"
COLUMN_NUMBER = 17
DATA_TYPE = ASCII_REAL
START_BYTE = 169
BYTES = 9
FORMAT = "E9.3"
UNIT = "METER"
DESCRIPTION = "Distance from Mars to Sun
at OCCULTATION TIME."
END_OBJECT = COLUMN
OBJECT = COLUMN
NAME = "LOCAL TRUE SOLAR TIME"
COLUMN_NUMBER = 18
DATA_TYPE = ASCII_REAL
START_BYTE = 179
BYTES = 6
FORMAT = "F6.3"
UNIT = "HOUR"
DESCRIPTION = "Local true solar time (LTST) at the
time and location of the occultation measurement. LTST at the
sub-solar longitude is defined as 12 solar hours. LTST on other
meridians changes by one solar hour for each 15 degree increment
in longitude. Thus, LTST for the occultation measurement is
given by 12 + (LONGITUDE_OF_PROFILE - SUB-SOLAR_LONGITUDE)/15."
END_OBJECT = COLUMN
OBJECT = COLUMN
NAME = "SOLAR ZENITH ANGLE"
COLUMN_NUMBER = 19
DATA_TYPE = ASCII_REAL
START_BYTE = 186
BYTES = 6
FORMAT = "F6.2"
UNIT = "DEGREE"
DESCRIPTION = "Angle between the direction to Sun
and local vertical direction on Mars at time and location of the
occultation measurement."
END_OBJECT = COLUMN
OBJECT = COLUMN
NAME = "SUN-EARTH-SPACECRAFT ANGLE"
COLUMN_NUMBER = 20
DATA_TYPE = ASCII_REAL
START_BYTE = 193
BYTES = 5
FORMAT = "F5.1"
UNIT = "DEGREE"
DESCRIPTION = "Approximate angle between Sun and
spacecraft as viewed from Earth during experiment."
END_OBJECT = COLUMN
OBJECT = COLUMN
NAME = "DSN ELEVATION ANGLE"
COLUMN_NUMBER = 21
DATA_TYPE = ASCII_REAL
START_BYTE = 199
BYTES = 5
FORMAT = "F5.1"
UNIT = "DEGREE"
DESCRIPTION = "Approximate angle between
direction to spacecraft and local horizon at DSN receiving
antenna during experiment."
END_OBJECT = COLUMN
OBJECT = COLUMN
NAME = "GRAVITY FIELD MODEL"
COLUMN_NUMBER = 22
DATA_TYPE = CHARACTER
START_BYTE = 206
BYTES = 12
FORMAT = "A12"
UNIT = "N/A"
DESCRIPTION = "File name of gravity field spherical
harmonic model used in defining reference areoid."
END_OBJECT = COLUMN
OBJECT = COLUMN
NAME = "PCK FILE NAME"
COLUMN_NUMBER = 23
DATA_TYPE = CHARACTER
START_BYTE = 221
BYTES = 12
FORMAT = "A12"
UNIT = "N/A"
DESCRIPTION = "File name of the NAIF Planetary
Constants File used in this retrieval and calculation (name
of the PCK file as stored in the MGS RST data system)."
END_OBJECT = COLUMN
OBJECT = COLUMN
NAME = "TRAJECTORY FILE NAME"
COLUMN_NUMBER = 24
DATA_TYPE = CHARACTER
START_BYTE = 236
BYTES = 12
FORMAT = "A12"
UNIT = "N/A"
DESCRIPTION = "File name of the spacecraft and
planetary ephemeris file used in this retrieval and calculation
(name of the file as stored in the MGS RST data system)."
END_OBJECT = COLUMN
OBJECT = COLUMN
NAME = "SPACECRAFT ATTITUDE FILE NAME"
COLUMN_NUMBER = 25
DATA_TYPE = CHARACTER
START_BYTE = 251
BYTES = 12
FORMAT = "A12"
UNIT = "N/A"
DESCRIPTION = "File name of the spacecraft
attitude file used in this retrieval and calculation (name
of the file as stored in the MGS RST data system). Left
blank if not known or no attitude file was used."
END_OBJECT = COLUMN
OBJECT = COLUMN
NAME = "ELECTRON DENSITY FILE NAME"
COLUMN_NUMBER = 26
DATA_TYPE = CHARACTER
START_BYTE = 266
BYTES = 12
FORMAT = "A12"
UNIT = "N/A"
DESCRIPTION = "File name of the electron
density profile from which this summary line was taken."
END_OBJECT = COLUMN
END_OBJECT = TABLE
END
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