OBJECT = COLUMN NAME = MET COLUMN_NUMBER = 1 BYTES = 4 DATA_TYPE = MSB_UNSIGNED_INTEGER START_BYTE = 1 UNIT = Seconds DESCRIPTION = "Mission elapsed time, in seconds, corresponding to the start of the accumulation period for the spectra." END_OBJECT = COLUMN OBJECT = COLUMN NAME = ACCUM_TIME COLUMN_NUMBER = 2 BYTES = 4 DATA_TYPE = MSB_UNSIGNED_INTEGER START_BYTE = 5 UNIT = Seconds DESCRIPTION = "Accumulation time, in seconds, of the Shield detector." END_OBJECT = COLUMN OBJECT = COLUMN NAME = MIDPOINT_MET COLUMN_NUMBER = 3 BYTES = 4 DATA_TYPE = MSB_UNSIGNED_INTEGER START_BYTE = 9 UNIT = Seconds DESCRIPTION = "The mission elapsed time at the midpoint of the shield Raw observation. Defined as: MET at the start of the observation + (ACCUM_TIME / 2)." END_OBJECT = COLUMN OBJECT = COLUMN NAME = ORBIT_NUMBER COLUMN_NUMBER = 4 BYTES = 2 DATA_TYPE = MSB_UNSIGNED_INTEGER START_BYTE = 13 DESCRIPTION = "Orbit number is a unique identifier for a given orbit of the MESSENGER spacecraft around Mercury. Orbit number is defined as starting at apoherm and is calculated using the MET value and the appropriate SPICE kernels. Orbit numbering does not start until MESSENGER performs the Mercury orbit insertion. Until that time the value for orbit Number is 0." END_OBJECT = COLUMN OBJECT = COLUMN NAME = INITIAL_ENERGY COLUMN_NUMBER = 5 BYTES = 4 DATA_TYPE = IEEE_REAL START_BYTE = 15 DESCRIPTION = "The energy of the middle of the first bin of the FAST and THERMAL NEURTON HPGE spectra." END_OBJECT = COLUMN OBJECT = COLUMN NAME = GRS_PRIORITY_LEVEL COLUMN_NUMBER = 6 BYTES = 2 DATA_TYPE = MSB_UNSIGNED_INTEGER START_BYTE = 19 DESCRIPTION = "Indicates the type of priority assigned to the science packet. The priority level is tied to the ApID of the packet. Priority level varies from 0-3, 0 being highest and 3 being lowest priority." END_OBJECT = COLUMN OBJECT = COLUMN NAME = BAD_DATA_FLAG COLUMN_NUMBER = 7 BYTES = 2 DATA_TYPE = MSB_UNSIGNED_INTEGER START_BYTE = 21 DESCRIPTION = "Intended for use as a bit-string bad data flag to indicate specific problems associated with the data. Values are expected to be assigned to specific bits as problems are identified during the course of the mission. Bit 1 - The high voltage is not on, is being ramped or has not been stable long enough. Bit 2 - Indicates a change in the analog pulse processing system gain setting. Bit 3 - Indicates a spectrum where the temperatures used for correction have fluctuated by greater than 5 percent from previous readings. Bit 4 - Indicates gamma spectra collected during a solar particle event. These spectra should not be combined with spectra collected under normal solar conditions. Bit 5 - Pulser data is not combined with the spectrum. Bit 6 - Indicates gamma spectra collected during a solar flare event. These spectra should not be combined with spectra collected under normal solar conditions. Bit 7 - Indicates gamma spectra collected during periods of decreased GS detector spectral resolution. These spectra should not be combined with spectra collected under 'normal' detector conditions. Bit 8 - Not all data channels were received on the ground. Bit 9 - Indicates a unique problem with single spectrum. Bit 10 - The high voltage has not been stable long enough. Bit 11 - This data was taken during a time when the spectra were particularly noisy. Many channels have far too many counts, especially the lower channels." END_OBJECT = COLUMN OBJECT = COLUMN NAME = NUM_BUFFERED_EVENTS COLUMN_NUMBER = 8 BYTES = 2 DATA_TYPE = MSB_UNSIGNED_INTEGER START_BYTE = 23 DESCRIPTION = "The number of bytes in the raw event buffer. The number of events in the raw event buffer is (Raw Bytes-16)/8. The number of raw events in the buffer will range from 0 to 126. Note there must be at least one event in the buffer before the Event Buffer Header will be generated." END_OBJECT = COLUMN OBJECT = COLUMN NAME = NUM_RAW_EVENTS COLUMN_NUMBER = 9 BYTES = 2 DATA_TYPE = MSB_UNSIGNED_INTEGER START_BYTE = 25 DESCRIPTION = "This value contains a count of the total number of raw events detected and is not limited by the length of the buffer. This counter will rollover if the count exceeds 65535." END_OBJECT = COLUMN OBJECT = COLUMN NAME = ZCT_THERMAL_MIN COLUMN_NUMBER = 10 BYTES = 2 DATA_TYPE = MSB_UNSIGNED_INTEGER START_BYTE = 27 DESCRIPTION = "Window parameter that sets the minimum acceptable time difference between shield and HpGe triggers for an event to be considered a thermal neutron. Units are 100 ns/tick. Parameter is inclusive, i.e., values equal to this parameter are accepted." END_OBJECT = COLUMN OBJECT = COLUMN NAME = ZCT_THERM_MAX COLUMN_NUMBER = 11 BYTES = 2 DATA_TYPE = MSB_UNSIGNED_INTEGER START_BYTE = 29 DESCRIPTION = "Window parameter that sets the maximum acceptable time difference between shield and HpGe triggers for an event to be considered a thermal neutron. Units are 100 ns/tick. Parameter is exclusive, i.e., values equal to this parameter are rejected" END_OBJECT = COLUMN OBJECT = COLUMN NAME = ZCT_FAST_MIN COLUMN_NUMBER = 12 BYTES = 2 DATA_TYPE = MSB_UNSIGNED_INTEGER START_BYTE = 31 DESCRIPTION = "Window parameter that sets the minimum acceptable time difference between shield and HpGe triggers for an event to be considered a fast neutron. Units are 100 ns/tick. Parameter is inclusive, i.e., values equal to this parameter are accepted." END_OBJECT = COLUMN OBJECT = COLUMN NAME = ZCT_FAST_MAX COLUMN_NUMBER = 13 BYTES = 2 DATA_TYPE = MSB_UNSIGNED_INTEGER START_BYTE = 33 DESCRIPTION = "Window parameter that sets the maximum time difference between shield and HpGe triggers for an event to be considered a fast neutron. Units are 100 ns/tick. Parameter is exclusive, i.e., values equal to this parameter are rejected." END_OBJECT = COLUMN OBJECT = COLUMN NAME = SHIELD_SHIFTS_RAW COLUMN_NUMBER = 14 BYTES = 2 DATA_TYPE = MSB_UNSIGNED_INTEGER START_BYTE = 35 DESCRIPTION = "The number of right shifts (divide by 2s) that are applied to raw shield pulse heights prior to binning in the Shield All Events spectrum. Possible values are 2 or 3. A value of two effectively increases the binning resolution but decreases the dynamic range (maximum binned energy)." END_OBJECT = COLUMN OBJECT = COLUMN NAME = SHIELD_SHIFTS_NEUTRON COLUMN_NUMBER = 15 BYTES = 2 DATA_TYPE = MSB_UNSIGNED_INTEGER START_BYTE = 37 DESCRIPTION = "The number of right shifts (divide by 2s) that are applied to raw shield pulse heights prior to binning in either the Shield Thermal Events spectrum or the Shield Fast Events spectrum. Possible values are 2 or 3. A value of two effectively increases the binning resolution but decreases the dynamic range (maximum binned energy)." END_OBJECT = COLUMN OBJECT = COLUMN NAME = HPGE_THERMAL COLUMN_NUMBER = 16 BYTES = 256 DATA_TYPE = IEEE_REAL START_BYTE = 39 ITEMS = 64 ITEM_BYTES = 4 DESCRIPTION = "Thermal Neutron spectrum about the 478-keV line, normalized to 0.60 keV energy bins." END_OBJECT = COLUMN OBJECT = COLUMN NAME = HPGE_FAST COLUMN_NUMBER = 17 BYTES = 256 DATA_TYPE = IEEE_REAL START_BYTE = 295 ITEMS = 64 ITEM_BYTES = 4 DESCRIPTION = "Fast Neutron spectrum about the 478-keV line, normalized to 0.60 keV energy bins." END_OBJECT = COLUMN OBJECT = COLUMN NAME = SHIELD_THERMAL COLUMN_NUMBER = 18 BYTES = 256 DATA_TYPE = MSB_UNSIGNED_INTEGER START_BYTE = 551 ITEMS = 128 ITEM_BYTES = 2 DESCRIPTION = "Raw Thermal Neutron spectrum about the 478-keV line." END_OBJECT = COLUMN OBJECT = COLUMN NAME = SHIELD_FAST COLUMN_NUMBER = 19 BYTES = 256 DATA_TYPE = MSB_UNSIGNED_INTEGER START_BYTE = 807 ITEMS = 128 ITEM_BYTES = 2 DESCRIPTION = "Raw Fast Neutron spectrum about the 478-keV line." END_OBJECT = COLUMN OBJECT = COLUMN NAME = UTC_MIDPOINT_MET COLUMN_NUMBER = 20 BYTES = 23 DATA_TYPE = CHARACTER START_BYTE = 1063 DESCRIPTION = "midpoint_met converted to UTC, stored as yyyy-mm-ddThh:mm:ss.sss." END_OBJECT = COLUMN OBJECT = COLUMN NAME = MERCURY_CENTRIC_LATITUDE COLUMN_NUMBER = 21 BYTES = 8 DATA_TYPE = IEEE_REAL START_BYTE = 1086 UNIT = DEGREE DESCRIPTION = "Sub spacecraft latitude in Mercury fixed coordinates at the middle of the collection interval." END_OBJECT = COLUMN OBJECT = COLUMN NAME = MERCURY_CENTRIC_LONGITUDE COLUMN_NUMBER = 22 BYTES = 8 DATA_TYPE = IEEE_REAL START_BYTE = 1094 UNIT = DEGREE DESCRIPTION = "Sub spacecraft longitude in Mercury fixed coordinates at the middle of the collection interval. Longitude increases towards the East." END_OBJECT = COLUMN OBJECT = COLUMN NAME = INSTR_BORESIGHT_MERCURY_X COLUMN_NUMBER = 23 BYTES = 8 DATA_TYPE = IEEE_REAL START_BYTE = 1102 UNIT = Kilometers DESCRIPTION = "Sub instrument boresight (x component) in Mercury fixed coordinates at the middle of the collection interval." END_OBJECT = COLUMN OBJECT = COLUMN NAME = INSTR_BORESIGHT_MERCURY_Y COLUMN_NUMBER = 24 BYTES = 8 DATA_TYPE = IEEE_REAL START_BYTE = 1110 UNIT = Kilometers DESCRIPTION = "Sub instrument boresight (y component) in Mercury fixed coordinates at the middle of the collection interval." END_OBJECT = COLUMN OBJECT = COLUMN NAME = INSTR_BORESIGHT_MERCURY_Z COLUMN_NUMBER = 25 BYTES = 8 DATA_TYPE = IEEE_REAL START_BYTE = 1118 UNIT = Kilometers DESCRIPTION = "Sub instrument boresight (z component) in Mercury fixed coordinates at the middle of the collection interval." END_OBJECT = COLUMN OBJECT = COLUMN NAME = SCALT COLUMN_NUMBER = 26 BYTES = 8 DATA_TYPE = IEEE_REAL START_BYTE = 1126 UNIT = Kilometers DESCRIPTION = "Mercury centric altitude of the sub-spacecraft point in Mercury-fixed rotating frame at the middle of the collection interval." END_OBJECT = COLUMN OBJECT = COLUMN NAME = DELTA_ANGLE COLUMN_NUMBER = 27 BYTES = 8 DATA_TYPE = IEEE_REAL START_BYTE = 1134 UNIT = DEGREE DESCRIPTION = "Difference between instrument +y direction and true north at the middle of the collection interval." END_OBJECT = COLUMN OBJECT = COLUMN NAME = MERCURY_SOL COLUMN_NUMBER = 28 BYTES = 8 DATA_TYPE = IEEE_REAL START_BYTE = 1142 UNIT = DEGREE DESCRIPTION = "Longitude of the Sun at 0 hours UT on the date of the record. Taken from the Association of Lunar and Planetary Observers 'Ephemeris for Physical Observation of Mercury'." END_OBJECT = COLUMN OBJECT = COLUMN NAME = LOCAL_HOUR COLUMN_NUMBER = 29 BYTES = 1 DATA_TYPE = MSB_UNSIGNED_INTEGER START_BYTE = 1150 UNIT = Hours DESCRIPTION = "Local Sun hour at the sub-spacecraft point." END_OBJECT = COLUMN OBJECT = COLUMN NAME = LOCAL_MINUTE COLUMN_NUMBER = 30 BYTES = 1 DATA_TYPE = MSB_UNSIGNED_INTEGER START_BYTE = 1151 UNIT = Minutes DESCRIPTION = "Local Sun minute at the sub-spacecraft point." END_OBJECT = COLUMN OBJECT = COLUMN NAME = POINTING COLUMN_NUMBER = 31 BYTES = 1 DATA_TYPE = BOOLEAN START_BYTE = 1152 DESCRIPTION = "True if pointing data was available." END_OBJECT = COLUMN OBJECT = COLUMN NAME = INTERSECTING COLUMN_NUMBER = 32 BYTES = 1 DATA_TYPE = BOOLEAN START_BYTE = 1153 DESCRIPTION = "True if the pointing vector intersects Mercury." END_OBJECT = COLUMN OBJECT = COLUMN NAME = NADIR_ANGLE COLUMN_NUMBER = 33 BYTES = 8 DATA_TYPE = IEEE_REAL START_BYTE = 1154 UNIT = DEGREE DESCRIPTION = "Spacecraft attitude during orbits and flybys is defined by two additional coordinate systems, the GRS LVLH (Local Vertical Local Horizontal) frame and the spacecraft fixed frame, and by the rotation of the spacecraft frame with respect to the GRS LVLH frame. In the GRS LVLH frame, the Z axis is aligned with the vector from the spacecraft to the planet center (the nadir direction), the Y axis is the negative of the cross product of the position and velocity vectors, and the X axis points in the instantaneous direction of motion, completing a right-handed coordinate system. The Z axis is along the viewing direction of the instrument deck inside the adapter ring and of the GRS just outside the adapter ring, the Y axis is directed from the spacecraft along the magnetometer boom, and the X-axis is parallel to the solar panel booms, forming a right-handed coordinate system. The spacecraft attitude is specified by the rotation of the spacecraft fixed frame Z axis in the GRS LVLH frame and a twist angle about the Z axis. The Z axis rotation is given by a nadir angle and an azimuth angle, where the nadir angle is 0 degrees when the spacecraft Z axis points along the + Z LVLH axis and 180 degrees when it points along -Z in the LVLH frame, and the LVLH azimuth angle is measured counterclockwise about the Z LVLH axis from the X LVLH axis. The twist angle is measured positive about the +Z spacecraft axis. See section 5.4.2 in the GRS_CDR_SIS for further details." END_OBJECT = COLUMN OBJECT = COLUMN NAME = AZIMUTH COLUMN_NUMBER = 34 BYTES = 8 DATA_TYPE = IEEE_REAL START_BYTE = 1162 UNIT = DEGREE DESCRIPTION = "Spacecraft attitude during orbits and flybys is defined by two additional coordinate systems, the GRS LVLH (Local Vertical Local Horizontal) frame and the spacecraft fixed frame, and by the rotation of the spacecraft frame with respect to the GRS LVLH frame. In the GRS LVLH frame, the Z axis is aligned with the vector from the spacecraft to the planet center (the nadir direction), the Y axis is the negative of the cross product of the position and velocity vectors, and the X axis points in the instantaneous direction of motion, completing a right-handed coordinate system. The Z axis is along the viewing direction of the instrument deck inside the adapter ring and of the GRS just outside the adapter ring, the Y axis is directed from the spacecraft along the magnetometer boom, and the X-axis is parallel to the solar panel booms, forming a right-handed coordinate system. The spacecraft attitude is specified by the rotation of the spacecraft fixed frame Z axis in the GRS LVLH frame and a twist angle about the Z axis. The Z axis rotation is given by a nadir angle and an azimuth angle, where the nadir angle is 0 degrees when the spacecraft Z axis points along the + Z LVLH axis and 180 degrees when it points along -Z in the LVLH frame, and the LVLH azimuth angle is measured counterclockwise about the Z LVLH axis from the X LVLH axis. The twist angle is measured positive about the +Z spacecraft axis. See section 5.4.2 in the GRS_CDR_SIS for further details." END_OBJECT = COLUMN OBJECT = COLUMN NAME = TWIST_ANGLE COLUMN_NUMBER = 35 BYTES = 8 DATA_TYPE = IEEE_REAL START_BYTE = 1170 UNIT = DEGREE DESCRIPTION = "Spacecraft attitude during orbits and flybys is defined by two additional coordinate systems, the GRS LVLH (Local Vertical Local Horizontal) frame and the spacecraft fixed frame, and by the rotation of the spacecraft frame with respect to the GRS LVLH frame. In the GRS LVLH frame, the Z axis is aligned with the vector from the spacecraft to the planet center (the nadir direction), the Y axis is the negative of the cross product of the position and velocity vectors, and the X axis points in the instantaneous direction of motion, completing a right-handed coordinate system. The Z axis is along the viewing direction of the instrument deck inside the adapter ring and of the GRS just outside the adapter ring, the Y axis is directed from the spacecraft along the magnetometer boom, and the X-axis is parallel to the solar panel booms, forming a right-handed coordinate system. The spacecraft attitude is specified by the rotation of the spacecraft fixed frame Z axis in the GRS LVLH frame and a twist angle about the Z axis. The Z axis rotation is given by a nadir angle and an azimuth angle, where the nadir angle is 0 degrees when the spacecraft Z axis points along the + Z LVLH axis and 180 degrees when it points along -Z in the LVLH frame, and the LVLH azimuth angle is measured counterclockwise about the Z LVLH axis from the X LVLH axis. The twist angle is measured positive about the +Z spacecraft axis. See section 5.4.2 in the GRS_CDR_SIS for further details." END_OBJECT = COLUMN OBJECT = COLUMN NAME = AD_TEMP COLUMN_NUMBER = 36 BYTES = 8 DATA_TYPE = IEEE_REAL START_BYTE = 1178 UNIT = DEGC DESCRIPTION = "Channel 06, AD Temperature, smoothed and interpolated to the center of the collection interval." END_OBJECT = COLUMN OBJECT = COLUMN NAME = HVPS_TEMP COLUMN_NUMBER = 37 BYTES = 8 DATA_TYPE = IEEE_REAL START_BYTE = 1186 UNIT = DEGC DESCRIPTION = "HVPS Temperature, smoothed and interpolated to the center of the collection interval." END_OBJECT = COLUMN OBJECT = COLUMN NAME = HVPS_VOLT COLUMN_NUMBER = 38 BYTES = 8 DATA_TYPE = IEEE_REAL START_BYTE = 1194 UNIT = Volts DESCRIPTION = "HVPS Voltage, smoothed and interpolated to the center of the collection interval." END_OBJECT = COLUMN OBJECT = COLUMN NAME = HVPS_REF_VOLT COLUMN_NUMBER = 39 BYTES = 8 DATA_TYPE = IEEE_REAL START_BYTE = 1202 UNIT = Volts DESCRIPTION = "HVPS Reference Voltage, smoothed and interpolated to the center of the collection interval." END_OBJECT = COLUMN OBJECT = COLUMN NAME = PREAMP_TEMP COLUMN_NUMBER = 40 BYTES = 8 DATA_TYPE = IEEE_REAL START_BYTE = 1210 UNIT = DEGC DESCRIPTION = "Channel 04, Pre Amp Temperature, smoothed and interpolated to the center of the collection interval." END_OBJECT = COLUMN OBJECT = COLUMN NAME = SHAPER_TEMP COLUMN_NUMBER = 41 BYTES = 8 DATA_TYPE = IEEE_REAL START_BYTE = 1218 UNIT = DEGC DESCRIPTION = "Channel 05, Shaper Temperature, smoothed and interpolated to the center of the collection interval." END_OBJECT = COLUMN OBJECT = COLUMN NAME = HV_MONITOR COLUMN_NUMBER = 42 BYTES = 8 DATA_TYPE = IEEE_REAL START_BYTE = 1226 UNIT = Volts DESCRIPTION = "Channel 07, HV Monitor, smoothed and interpolated to the center of the collection interval." END_OBJECT = COLUMN OBJECT = COLUMN NAME = HPGE_RAW_EVENTS COLUMN_NUMBER = 43 BYTES = 4 DATA_TYPE = MSB_UNSIGNED_INTEGER START_BYTE = 1234 DESCRIPTION = "Counter of HPGe Raw events." END_OBJECT = COLUMN OBJECT = COLUMN NAME = SHIELD_RAW_EVENTS COLUMN_NUMBER = 44 BYTES = 4 DATA_TYPE = MSB_UNSIGNED_INTEGER START_BYTE = 1238 DESCRIPTION = "Counter for SHIELD raw events." END_OBJECT = COLUMN OBJECT = COLUMN NAME = ACCUMULATED_DEAD_TIME COLUMN_NUMBER = 45 BYTES = 4 DATA_TYPE = MSB_UNSIGNED_INTEGER START_BYTE = 1242 DESCRIPTION = "Counter for accumulated dead time." END_OBJECT = COLUMN