PDS_VERSION_ID = PDS3 RECORD_TYPE = "STREAM" RECORD_BYTES = 126 /* for SPREADSHEET */ ^ASCII_DOCUMENT = "nh_spin_state_v04.asc" ^HEADER = ( "nh_spin_state_v04.csv", 1 ) ^SPREADSHEET = ( "nh_spin_state_v04.csv", 81 ) DATA_SET_ID = "NH-J/P/SS-SPICE-6-V1.0" PRODUCT_CREATION_TIME = 2021-01-20T00:00:00 PRODUCT_ID = "NH SPIN STATE HISTORY VERSION 04" DESCRIPTION = " These documents record the start and end times of the periods of attitude control states history of the New Horizons spacecraft. It is based on angular speed around the spacecraft Y axis, as determined from the C-Kernels in this data set. The New Horizons spacecraft operated in either two primary attitude control states: spinning; 3-axis stabilized. Generally speaking, spin state is for hibernation operations and 3-axis state is for everything else e.g. taking observations. In hibernation, the spacecraft rolls at about five revolutions per minute (5RPM) around its Y axis, which is nominally parallel to the boresight of the High-Gain Antenna (HG), and it maintains the HGA pointed toward earth. The tables here were generated by querying the attitude and angular velocities stored in the C-Kernels of this data set at 1024s intervals, determining the rotation rate about the Y axis. An arbitrary rotation rate of 2.5RPM about the Y axis was chosen as a knife-edge trigger to define when the spacecraft was in Spinning state (> 2.5RPM) or in 3-axis state (< 2.5RPM). When a change in attitude is detected, binary search is used the find the time of the change to the nearest second. Gaps in the data are ignored in that they are never assumed to change the state in themselves, only when the following state is different than the previous. " OBJECT = ASCII_DOCUMENT DOCUMENT_NAME = "NH SPIN STATE HISTORY DATA - 1 TRANSITIION PER LINE" DOCUMENT_TOPIC_TYPE = "DATA SET DESCRIPTION" INTERCHANGE_FORMAT = "ASCII" DOCUMENT_FORMAT = "TEXT" PUBLICATION_DATE = 2021-01-20 DESCRIPTION = "This is an ASCII text file composing a table of New Horizons spacecraft attitude control state history. Each line in the table records either a start or end time of a period when the spacecraft was in one of its two primary attitude control states i.e. spinning or 3-axis stabilized. " END_OBJECT = ASCII_DOCUMENT OBJECT = HEADER BYTES = 80 HEADER_TYPE = "TEXT" INTERCHANGE_FORMAT = "ASCII" DESCRIPTION = "SPREADSHEET column headers; see SPREADSHEET OBJECT" END_OBJECT = HEADER OBJECT = SPREADSHEET DOCUMENT_NAME = "NH SPIN STATE HISTORY DATA - 1 STATE PER LINE" FIELD_DELIMITER = "COMMA" FIELDS = 8 ROW_BYTES = 126 ROWS = 56 DESCRIPTION = "This is a SPREADSHEET object composing a table of New Horizons spacecraft attitude control state history. Each line in the table records start and end times of a period when the spacecraft was in one of its two primary attitude control states i.e. spinning or 3-axis stabilized. The time resolution is to the nearest second. " OBJECT = FIELD NAME = "START UTC" FIELD_NUMBER = 1 BYTES = 19 DATA_TYPE = TIME DESCRIPTION = "The start UTC of the time period on this row." END_OBJECT = FIELD OBJECT = FIELD NAME = "END UTC" FIELD_NUMBER = 2 BYTES = 19 DATA_TYPE = TIME DESCRIPTION = "The end UTC of the time period on this row." END_OBJECT = FIELD OBJECT = FIELD NAME = "ATTITUDE CONTROL STATE" FIELD_NUMBER = 3 BYTES = 4 FORMAT = "A4" DATA_TYPE = CHARACTER DESCRIPTION = "A code representing the attitude control state" END_OBJECT = FIELD OBJECT = FIELD NAME = "RPM AT ENTRY" FIELD_NUMBER = 4 BYTES = 5 FORMAT = "F5.3" DATA_TYPE = ASCII_REAL UNIT = "RPM" DESCRIPTION = "The spin rate of the spacecraft at the entry to this mode at time START UTC in FIELD 1, in RPM. The value will be greater or less than 2.5RPM for spinning or 3-axis state, respectively. " END_OBJECT = FIELD OBJECT = FIELD NAME = "RPM AT EXIT" FIELD_NUMBER = 5 BYTES = 5 FORMAT = "F5.3" DATA_TYPE = ASCII_REAL UNIT = "RPM" DESCRIPTION = "The spin rate of the spacecraft at the exit from this mode at time END UTC in FIELD 1, in RPM. The value will be greater or less than 2.5RPM for spinning or 3-axis state, respectively. " END_OBJECT = FIELD OBJECT = FIELD NAME = "FIRST COMMENT" FIELD_NUMBER = 6 BYTES = 33 FORMAT = "A33" DATA_TYPE = CHARACTER DESCRIPTION = "First comment from the algorithm that wrote this SPREADSHEET; will indicate where gaps in coverage might exist in or around the time period of this row. " END_OBJECT = FIELD OBJECT = FIELD NAME = "SECOND COMMENT" FIELD_NUMBER = 7 BYTES = 32 FORMAT = "A33" DATA_TYPE = CHARACTER DESCRIPTION = "Second comment from the algorithm that wrote this SPREADSHEET; will indicate where gaps in coverage might exist in or around the time period of this row. " END_OBJECT = FIELD OBJECT = FIELD NAME = "THIRD COMMENT" FIELD_NUMBER = 8 BYTES = 1 FORMAT = "A33" DATA_TYPE = CHARACTER DESCRIPTION = "Third comment from the algorithm that wrote this SPREADSHEET; will indicate where gaps in coverage might exist in or around the time period of this row. As of release two, this field is always empty. " END_OBJECT = FIELD END_OBJECT = SPREADSHEET END