PDS_VERSION_ID = PDS3 RECORD_TYPE = FIXED_LENGTH RECORD_BYTES = 502 FILE_RECORDS = 944 ^OBSERVATION_TABLE = "OBSCMIDX.TAB" DATA_SET_ID = "HST-S-WFPC2-3-RPX-V1.0" PRODUCT_CREATION_TIME = 1998-09-21T00:00:00 SPACECRAFT_NAME = "HUBBLE SPACE TELESCOPE" SPACECRAFT_ID = HST INSTRUMENT_NAME = "WIDE FIELD PLANETARY CAMERA 2" INSTRUMENT_ID = WFPC2 TARGET_NAME = SATURN OBJECT = OBSERVATION_TABLE INTERCHANGE_FORMAT = ASCII ROWS = 944 COLUMNS = 37 ROW_BYTES = 502 INDEX_TYPE = CUMULATIVE DESCRIPTION = "This is a table of descriptive information about the images found on all five CDROM volumes. There is one record per 'ring observation,' i.e. image, spectrum, or occultation profile. This is the level at which data products are cataloged by the PDS Rings Node. Note that each data file in this data set is associated with four different ring observations, corresponding to the PC1, WF2, WF3 and WF4 fields of view of the Wide Field/Planetary Camera 2. Note also that multiple data files are associated with any single ring observation, such as a raw data file, a calibrated data file, a browse image, etc. This table emphasizes the geometric and photometric properties of each image. See the corresponding CUMINDEX.TAB file for some of the instrument and mission-specific parameters of each image. CUMINDEX.TAB also contains a complete list of all the data files on all five CDROMs." OBJECT = COLUMN NAME = RING_OBSERVATION_ID DATA_TYPE = CHARACTER START_BYTE = 2 BYTES = 39 FORMAT = "A39" UNIT = 'N/A' DESCRIPTION = "The RING_OBSERVATION_ID provides a unique identifier for each scientific observation (image, spectrum, occultation profile, etc.) cataloged by the PDS Rings Node. An example from this data set is 'S/IMG/HST/WFPC2/1995-08-09/U2TF0101/PC1'. Here 1995-08-09 specifies the date of the particular observation, and U2TF0101 is the unique image identification provided by Space Telescope Science Institute. Finally, PC1 indicates that this refers the the image acquired by the Planetary Camera of WFPC2 (as opposed to the Wide Field Cameras WF2, WF3 or WF4)." END_OBJECT = COLUMN OBJECT = COLUMN NAME = PLANET DATA_TYPE = CHARACTER START_BYTE = 44 BYTES = 7 FORMAT = "A7" UNIT = 'N/A' DESCRIPTION = "Name of the planet. In this data set, the value is always SATURN." END_OBJECT = COLUMN OBJECT = COLUMN NAME = START_TIME DATA_TYPE = CHARACTER START_BYTE = 54 BYTES = 19 FORMAT = "A19" UNIT = 'N/A' DESCRIPTION = "UTC date and time at which camera shutter opened, in PDS format ('yyyy-mm-ddThh:mm:ss')." END_OBJECT = COLUMN OBJECT = COLUMN NAME = RING_EVENT_START_TIME DATA_TYPE = CHARACTER START_BYTE = 76 BYTES = 19 FORMAT = "A19" UNIT = 'N/A' DESCRIPTION = "UTC date and time at which a photon left Saturn if it arrived at HST the moment the camera shutter opened, in PDS format ('yyyy-mm-ddThh:mm:ss'). The difference between this time and the START_TIME value is the light travel time from Saturn to Earth." END_OBJECT = COLUMN OBJECT = COLUMN NAME = EXPOSURE_DURATION DATA_TYPE = ASCII_REAL START_BYTE = 97 BYTES = 7 FORMAT = "F7.2" UNIT = "s" DESCRIPTION = "Duration of the exposure, in seconds." END_OBJECT = COLUMN OBJECT = COLUMN NAME = NAME DATA_TYPE = CHARACTER START_BYTE = 106 BYTES = 16 FORMAT = "A16" UNIT = 'N/A' DESCRIPTION = "Name of the PDS IMAGE object as given in the PDS label. Possible values are TARGETED_IMAGE and UNTARGETED_IMAGE. TARGETED_IMAGE indicates that this is the primary WFPC2 field targeted by the P.I.; UNTARGETED_IMAGE indicates that it is one of the other three images acquired at the same time. Note however that UNTARGETED_IMAGEs often contain additional components of the ring and satellite system." END_OBJECT = COLUMN OBJECT = COLUMN NAME = IMAGE_LINES DATA_TYPE = ASCII_INTEGER START_BYTE = 124 BYTES = 3 FORMAT = "I3" UNIT = 'N/A' DESCRIPTION = "Number of lines and samples in the image. Note that WFPC2 images are always square." END_OBJECT = COLUMN OBJECT = COLUMN NAME = PIXEL_FIELD_OF_VIEW DATA_TYPE = ASCII_REAL START_BYTE = 128 BYTES = 9 FORMAT = "F9.7" UNIT = "deg" DESCRIPTION = "The approximate horizontal and vertical angular size of field of view of a single pixel. WFPC2 pixels are very nearly square. Note that the pixel grids on WFPC2 are not perfectly rectangular, however; always use the field-of-view distortion models when reconstructing the geometry of a WFPC2 image." END_OBJECT = COLUMN OBJECT = COLUMN NAME = FIELD_OF_VIEW DATA_TYPE = ASCII_REAL START_BYTE = 138 BYTES = 6 FORMAT = "F6.4" UNIT = "deg" DESCRIPTION = "The approximate horizontal and vertical angular size of field of view of the full image. WFPC2 images are very nearly square. Note that the pixel grids on WFPC2 are not perfectly rectangular, however; always use the field-of-view distortion models when reconstructing the geometry of a WFPC2 image." END_OBJECT = COLUMN OBJECT = COLUMN NAME = FILTER_NAME DATA_TYPE = CHARACTER START_BYTE = 146 BYTES = 13 FORMAT = "A13" UNIT = 'N/A' DESCRIPTION = "Name of the filter used for the exposure. Equivalent to FITS keywords FILTNAM1 and FILTNAM2. If two filters were used, their names are concatenated with a '+' separator." END_OBJECT = COLUMN OBJECT = COLUMN NAME = GAIN_MODE_ID DATA_TYPE = CHARACTER START_BYTE = 162 BYTES = 5 FORMAT = "A5" UNIT = 'N/A' DESCRIPTION = "The gain mode used for the particular image. Possible values are A2D7 and A2D15. Found in the value of FITS keyword PHOTMODE." END_OBJECT = COLUMN OBJECT = COLUMN NAME = WAVELENGTH DATA_TYPE = ASCII_REAL START_BYTE = 169 BYTES = 6 FORMAT = "F6.4" NULL_CONSTANT = 0. UNIT = "micrometers" DESCRIPTION = "Median wavelength of the light collected by the image, in micrometers, after convolving the filter and instrument response with the solar spectrum. If the value is unavailable, 0 appears in this column." END_OBJECT = COLUMN OBJECT = COLUMN NAME = MINIMUM_WAVELENGTH DATA_TYPE = ASCII_REAL START_BYTE = 176 BYTES = 6 FORMAT = "F6.4" NULL_CONSTANT = 0. UNIT = "micrometers" DESCRIPTION = "Rough lower limit of the wavelength of the light collected by the image, in micrometers, after convolving the filter and instrument response with the solar spectrum. If the value is unavailable, 0 appears in this column. More precisely, this is the wavelength such that 95% of the light energy recorded has a longer wavelength and 5% has a shorter wavelength." END_OBJECT = COLUMN OBJECT = COLUMN NAME = MAXIMUM_WAVELENGTH DATA_TYPE = ASCII_REAL START_BYTE = 183 BYTES = 6 FORMAT = "F6.4" NULL_CONSTANT = 0. UNIT = "micrometers" DESCRIPTION = "Rough upper limit of the wavelength of the light collected by the image, in micrometers, after convolving the filter and instrument response with the solar spectrum. If the value is unavailable, 0 appears in this column. More precisely, this is the wavelength such that 5% of the light energy recorded has a longer wavelength and 95% has a shorter wavelength." END_OBJECT = COLUMN OBJECT = COLUMN NAME = RADIANCE_SCALING_FACTOR DATA_TYPE = ASCII_REAL START_BYTE = 190 BYTES = 10 FORMAT = "E10.4" NULL_CONSTANT = 0. UNIT = 'erg/s/cm^2/micrometer/sr' DESCRIPTION = "This constant, when multiplied by the data numbers in a calibrated image file, yields the approximate value for radiance, in units of erg/s/cm^2/micrometer/steradian. If the value is unavailable, 0 appears in this column." END_OBJECT = COLUMN OBJECT = COLUMN NAME = REFLECTANCE_SCALING_FACTOR DATA_TYPE = ASCII_REAL START_BYTE = 201 BYTES = 10 FORMAT = "E10.4" NULL_CONSTANT = 0. UNIT = 'N/A' DESCRIPTION = "This constant, when multiplied by the data numbers in a calibrated image file, yields the approximate value for reflectance (I/F) at Saturn. If the value is unavailable, 0 appears in this column." END_OBJECT = COLUMN OBJECT = COLUMN NAME = PHASE_ANGLE DATA_TYPE = ASCII_REAL START_BYTE = 212 BYTES = 7 FORMAT = "F7.4" UNIT = "deg" DESCRIPTION = "The phase angle (Sun-target-Earth angle) at the center of the targeted image at Saturn, in degrees." END_OBJECT = COLUMN OBJECT = COLUMN NAME = INCIDENCE_ANGLE DATA_TYPE = ASCII_REAL START_BYTE = 220 BYTES = 7 FORMAT = "F7.4" UNIT = "deg" DESCRIPTION = "The Saturn ring plane incidence angle, in degrees. I.e., the angle between the direction of the incoming photons and the ring plane normal vector. Values always fall between 0 and 90." END_OBJECT = COLUMN OBJECT = COLUMN NAME = EMISSION_ANGLE DATA_TYPE = ASCII_REAL START_BYTE = 228 BYTES = 7 FORMAT = "F7.4" UNIT = "deg" DESCRIPTION = "The Saturn ring plane emission angle, in degrees. I.e., the angle between the direction of the photons toward Earth and the ring plane normal vector. Values fall between 0 and 90 if the lit side of the rings is visible from Earth; values >90 when the unlit side is visible." END_OBJECT = COLUMN OBJECT = COLUMN NAME = NOTE DATA_TYPE = CHARACTER START_BYTE = 237 BYTES = 70 FORMAT = "A70" UNIT = 'N/A' DESCRIPTION = "First note field provided by the Principal Investigator and by Space Telescope Science Institute." END_OBJECT = COLUMN OBJECT = COLUMN NAME = SC_TARGET_POSITION_VECTOR_X DATA_TYPE = ASCII_REAL START_BYTE = 309 BYTES = 15 FORMAT = "F15.3" UNIT = "km" DESCRIPTION = "X-component of the position vector from the spacecraft to Saturn, in J2000 coordinates." END_OBJECT = COLUMN OBJECT = COLUMN NAME = SC_TARGET_POSITION_VECTOR_Y DATA_TYPE = ASCII_REAL START_BYTE = 325 BYTES = 15 FORMAT = "F15.3" UNIT = "km" DESCRIPTION = "Y-component of the position vector from the spacecraft to Saturn, in J2000 coordinates." END_OBJECT = COLUMN OBJECT = COLUMN NAME = SC_TARGET_POSITION_VECTOR_Z DATA_TYPE = ASCII_REAL START_BYTE = 341 BYTES = 15 FORMAT = "F15.3" UNIT = "km" DESCRIPTION = "Z-component of the position vector from the spacecraft to Saturn, in J2000 coordinates." END_OBJECT = COLUMN OBJECT = COLUMN NAME = SC_TARGET_VELOCITY_VECTOR_X DATA_TYPE = ASCII_REAL START_BYTE = 357 BYTES = 7 FORMAT = "F7.3" UNIT = "km/s" DESCRIPTION = "X-component of the velocity vector of Saturn relative to the spacecraft, in J2000 coordinates." END_OBJECT = COLUMN OBJECT = COLUMN NAME = SC_TARGET_VELOCITY_VECTOR_Y DATA_TYPE = ASCII_REAL START_BYTE = 365 BYTES = 7 FORMAT = "F7.3" UNIT = "km/s" DESCRIPTION = "Y-component of the velocity vector of Saturn relative to the spacecraft, in J2000 coordinates." END_OBJECT = COLUMN OBJECT = COLUMN NAME = SC_TARGET_VELOCITY_VECTOR_Z DATA_TYPE = ASCII_REAL START_BYTE = 373 BYTES = 7 FORMAT = "F7.3" UNIT = "km/s" DESCRIPTION = "Z-component of the velocity vector of Saturn relative to the spacecraft, in J2000 coordinates." END_OBJECT = COLUMN OBJECT = COLUMN NAME = SC_SUN_POSITION_VECTOR_X DATA_TYPE = ASCII_REAL START_BYTE = 381 BYTES = 15 FORMAT = "F15.3" UNIT = "km" DESCRIPTION = "X-component of the position vector from the spacecraft to the Sun, in J2000 coordinates." END_OBJECT = COLUMN OBJECT = COLUMN NAME = SC_SUN_POSITION_VECTOR_Y DATA_TYPE = ASCII_REAL START_BYTE = 397 BYTES = 15 FORMAT = "F15.3" UNIT = "km" DESCRIPTION = "Y-component of the position vector from the spacecraft to the Sun, in J2000 coordinates." END_OBJECT = COLUMN OBJECT = COLUMN NAME = SC_SUN_POSITION_VECTOR_Z DATA_TYPE = ASCII_REAL START_BYTE = 413 BYTES = 15 FORMAT = "F15.3" UNIT = "km" DESCRIPTION = "Z-component of the position vector from the spacecraft to the Sun, in J2000 coordinates." END_OBJECT = COLUMN OBJECT = COLUMN NAME = SC_SUN_VELOCITY_VECTOR_X DATA_TYPE = ASCII_REAL START_BYTE = 429 BYTES = 7 FORMAT = "F7.3" UNIT = "km/s" DESCRIPTION = "X-component of the velocity vector of the Sun relative to the spacecraft, in J2000 coordinates." END_OBJECT = COLUMN OBJECT = COLUMN NAME = SC_SUN_VELOCITY_VECTOR_Y DATA_TYPE = ASCII_REAL START_BYTE = 437 BYTES = 7 FORMAT = "F7.3" UNIT = "km/s" DESCRIPTION = "Y-component of the velocity vector of the Sun relative to the spacecraft, in J2000 coordinates." END_OBJECT = COLUMN OBJECT = COLUMN NAME = SC_SUN_VELOCITY_VECTOR_Z DATA_TYPE = ASCII_REAL START_BYTE = 445 BYTES = 7 FORMAT = "F7.3" UNIT = "km/s" DESCRIPTION = "Z-component of the velocity vector of the Sun relative to the spacecraft, in J2000 coordinates." END_OBJECT = COLUMN OBJECT = COLUMN NAME = RIGHT_ASCENSION DATA_TYPE = ASCII_REAL START_BYTE = 453 BYTES = 10 FORMAT = "F10.6" UNIT = "deg" DESCRIPTION = "J2000 right ascension at the center of the image's field of view, in degrees. Together, the right ascension, declination and twist angle values define the orientation of the image." END_OBJECT = COLUMN OBJECT = COLUMN NAME = DECLINATION DATA_TYPE = ASCII_REAL START_BYTE = 464 BYTES = 10 FORMAT = "F10.6" UNIT = "deg" DESCRIPTION = "J2000 declination at the center of the image's field of view, in degrees. Together, the right ascension, declination and twist angle values define the orientation of the image." END_OBJECT = COLUMN OBJECT = COLUMN NAME = TWIST_ANGLE DATA_TYPE = ASCII_REAL START_BYTE = 475 BYTES = 8 FORMAT = "F8.4" UNIT = "deg" DESCRIPTION = "The angle of rotation about the optical axis relative to celestial coordinates. Together, the right ascension, declination and twist angle values define the orientation of the image. The twist angle is given according to PDS default definition. The C-matrix transforms a 3-vector in celestial coordinates into a frame fixed to the image plane. Celestial coordinates refer to a frame in which the x-axis points toward the J2000 First Point of Aries and the z-axis points to the J2000 celestial pole. Image plane coordinates are defined such that the x-axis points right (the direction of increasing samples), the y-axis points down (opposite the direction of increasing lines), and the z-axis points along the camera's optic axis. The C-matrix is defined by: C = |-s1 c3 - c1 s2 s3 c1 c3 - s1 s2 s3 c2 s3| | s1 s3 - c1 s2 c3 -c1 s3 - s1 s2 c3 c2 c3| | c1 c2 s1 c2 s2 | where: s1 = sin(RIGHT_ASCENSION); c1 = cos(RIGHT_ASCENSION); s2 = sin(DECLINATION); c2 = cos(DECLINATION); s3 = sin(TWIST_ANGLE); c3 = cos(TWIST_ANGLE) " END_OBJECT = COLUMN OBJECT = COLUMN NAME = CELESTIAL_NORTH_CLOCK_ANGLE DATA_TYPE = ASCII_REAL START_BYTE = 484 BYTES = 8 FORMAT = "F8.4" UNIT = "deg" DESCRIPTION = "The direction angle of celestial north at the center of the image. It is measured from the 'upward' direction, clockwise to the direction toward J2000 celestial north, assuming the image is displayed with samples increasing toward the right and lines increasing upward." END_OBJECT = COLUMN OBJECT = COLUMN NAME = BODY_POLE_CLOCK_ANGLE DATA_TYPE = ASCII_REAL START_BYTE = 493 BYTES = 8 FORMAT = "F8.4" UNIT = "deg" DESCRIPTION = "The direction angle of Saturn's rotation axis in the image. It is measured from the 'upward' direction, clockwise to the direction of the north pole as projected into the image plane, assuming the image is displayed with samples increasing toward the right and lines increasing upward." END_OBJECT = COLUMN END_OBJECT = OBSERVATION_TABLE END