PDS_VERSION_ID = PDS3 RECORD_TYPE = FIXED_LENGTH RECORD_BYTES = 324 FILE_RECORDS = 223 ^TABLE = "003003AA.OCS" INSTRUMENT_HOST_NAME = "MARS GLOBAL SURVEYOR" TARGET_NAME = "MARS" INSTRUMENT_NAME = "RADIO SCIENCE SUBSYSTEM" DATA_SET_ID = "MGS-M-RSS-5-SDP-V1.0" PRODUCT_ID = "003003AA.OCS" PRODUCT_RELEASE_DATE = 2003-03-10 DESCRIPTION = "This file contains a summary of MGS radio occultation measurements of the neutral atmosphere of Mars." START_TIME = 2000-03-01T00:33:00Z STOP_TIME = 2000-03-31T23:51:00Z SOFTWARE_NAME = "OCS; V1.4" PRODUCT_CREATION_TIME = 2003-03-10T05:59:38Z PRODUCER_ID = "MGS RST" OBJECT = TABLE ROWS = 223 COLUMNS = 32 ROW_BYTES = 324 INTERCHANGE_FORMAT = ASCII DESCRIPTION = "Table contains one row for each radio science atmospheric temperature-pressure profile. Each row includes 32 data columns (321 total bytes), 1 ASCII blank character to pad out the record, and an ASCII carriage-return line-feed pair at the end." 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 geometrical ray path grazed the limb. This is computed by subtracting the limb-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 tangent to the ray path at the occultation point, measured positive from local north toward local east. The tangent to the ray path indicates the direction of signal propagation. A signal traveling from west toward east as it grazed the surface 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 AT SURFACE" COLUMN_NUMBER = 8 DATA_TYPE = ASCII_REAL START_BYTE = 96 BYTES = 7 FORMAT = "F7.3" UNIT = "DEGREE" DESCRIPTION = "Areocentric (north) latitude of the occultation point." 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 AT SURFACE. Set to -9.999 if not known." END_OBJECT = COLUMN OBJECT = COLUMN NAME = "LONGITUDE AT SURFACE" 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 of the occultation point in body fixed coordinates." 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 AT SURFACE. 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 the time of geometric occultation 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 = "RADIUS AT SURFACE" COLUMN_NUMBER = 15 DATA_TYPE = ASCII_REAL START_BYTE = 149 BYTES = 8 FORMAT = "F8.0" UNIT = "METER" DESCRIPTION = "Radius of Mars at the occultation point as estimated from these data." END_OBJECT = COLUMN OBJECT = COLUMN NAME = "SIGMA RADIUS" COLUMN_NUMBER = 16 DATA_TYPE = ASCII_REAL START_BYTE = 158 BYTES = 6 FORMAT = "F6.0" UNIT = "METER" DESCRIPTION = "One standard deviation uncertainty in RADIUS AT SURFACE. Set to -9999. if not known." END_OBJECT = COLUMN OBJECT = COLUMN NAME = "SURFACE PRESSURE" COLUMN_NUMBER = 17 DATA_TYPE = ASCII_REAL START_BYTE = 165 BYTES = 7 FORMAT = "F7.2" UNIT = "PASCAL" DESCRIPTION = "Atmospheric pressure at the occultation point -- i.e., at the point defined by RADIUS AT SURFACE, LATITUDE AT SURFACE, and LONGITUDE AT SURFACE. Obtained by extrapolating from the lowest sample in the retrieved atmospheric profile to the estimated RADIUS AT SURFACE." END_OBJECT = COLUMN OBJECT = COLUMN NAME = "SIGMA SURFACE PRESSURE" COLUMN_NUMBER = 18 DATA_TYPE = ASCII_REAL START_BYTE = 173 BYTES = 5 FORMAT = "F5.2" UNIT = "PASCAL" DESCRIPTION = "One standard deviation uncertainty in SURFACE PRESSURE. Set to -9.99 if not known." END_OBJECT = COLUMN OBJECT = COLUMN NAME = "TEMPERATURE NEAR SURFACE" COLUMN_NUMBER = 19 DATA_TYPE = ASCII_REAL START_BYTE = 179 BYTES = 6 FORMAT = "F6.2" UNIT = "KELVIN" DESCRIPTION = "Atmospheric temperature at lowest sample in temperature-pressure profile. Note that the height of this sample above the surface varies among profiles. No attempt has been made to extrapolate to surface because thermal structure of boundary layer varies strongly with local time." END_OBJECT = COLUMN OBJECT = COLUMN NAME = "SIGMA TEMPERATURE NEAR SURFACE" COLUMN_NUMBER = 20 DATA_TYPE = ASCII_REAL START_BYTE = 186 BYTES = 5 FORMAT = "F5.2" UNIT = "KELVIN" DESCRIPTION = "One standard deviation uncertainty in TEMPERATURE NEAR SURFACE." END_OBJECT = COLUMN OBJECT = COLUMN NAME = "SPACECRAFT TO LIMB DISTANCE" COLUMN_NUMBER = 21 DATA_TYPE = ASCII_REAL START_BYTE = 192 BYTES = 9 FORMAT = "E9.3" UNIT = "METER" DESCRIPTION = "Distance from spacecraft to occultation point at time when ray path grazed planetary surface." END_OBJECT = COLUMN OBJECT = COLUMN NAME = "SPACECRAFT TO DSN DISTANCE" COLUMN_NUMBER = 22 DATA_TYPE = ASCII_REAL START_BYTE = 202 BYTES = 9 FORMAT = "E9.3" UNIT = "METER" DESCRIPTION = "Distance from spacecraft to DSN receiving antenna at time when ray path grazed planetary surface." END_OBJECT = COLUMN OBJECT = COLUMN NAME = "LOCAL TRUE SOLAR TIME OF OCCULTATION" COLUMN_NUMBER = 23 DATA_TYPE = ASCII_REAL START_BYTE = 212 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_AT_SURFACE - SUB-SOLAR_LONGITUDE)/15." END_OBJECT = COLUMN OBJECT = COLUMN NAME = "SOLAR ZENITH ANGLE" COLUMN_NUMBER = 24 DATA_TYPE = ASCII_REAL START_BYTE = 219 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 = 25 DATA_TYPE = ASCII_REAL START_BYTE = 226 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 = 26 DATA_TYPE = ASCII_REAL START_BYTE = 232 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 = 27 DATA_TYPE = CHARACTER START_BYTE = 239 BYTES = 12 FORMAT = "A12" UNIT = "N/A" DESCRIPTION = "File name of gravity field spherical harmonic model used in profile retrieval and calculation of geopotential." END_OBJECT = COLUMN OBJECT = COLUMN NAME = "GEOPOTENTIAL REFERENCE" COLUMN_NUMBER = 28 DATA_TYPE = ASCII_REAL START_BYTE = 253 BYTES = 9 FORMAT = "F9.0" UNIT = "METER SQUARED PER SECOND SQUARED" DESCRIPTION = "Reference value for geopotential. Reference geoid has mean equatorial radius of 3396 kilometers." END_OBJECT = COLUMN OBJECT = COLUMN NAME = "PCK FILE NAME" COLUMN_NUMBER = 29 DATA_TYPE = CHARACTER START_BYTE = 264 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 = 30 DATA_TYPE = CHARACTER START_BYTE = 279 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 = 31 DATA_TYPE = CHARACTER START_BYTE = 294 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 = "TPS FILE NAME" COLUMN_NUMBER = 32 DATA_TYPE = CHARACTER START_BYTE = 309 BYTES = 12 FORMAT = "A12" UNIT = "N/A" DESCRIPTION = "File name of complete temperature- pressure profile from which these parameters derive." END_OBJECT = COLUMN END_OBJECT = TABLE END