The FUSE Mission Planning Schedule (MPS) timeline plots are generated for use by the Science and Operations team at JHU, but they can also be used by observers to place their observations on a timeline and in the context of orbital events and surrounding observations.

The plots are PDF files, usually with a day per page, and Day/Universal Time as the X-axis. Initially MPSs were approximately a day in length, but varied by at least a factor of two, depending on the events being planned. Later MPSs were usually multi-day schedules (up to 4 weeks in length) unless a re-delivery or re-plan had taken place. A variety of parameters are shown in sub-panels along the Y-axis of these plots. The parameters plotted on these plots have changed during the course of the mission, reflecting changing operational constraints and the evolution of MP tools. The following is a complete list of all possible parameters (and explanations) which appear in various MPS timeline plots. Following this list is a section detailing the time ranges for different combinations of plotted parameters.

Each timeline is labeled with the MPS filename, and also the MPS number (i.e. "MPS 223").

Each calendar day is broken into two panels each covering up to 12 hours.

A one day example of an MPS timeline plot.

Each panel contains rows that specify some combination of the following:

• RAM: The instantaneous angle of the telescope boresight to the direction of spacecraft motion.
  
  
• LIMB: The angle of the boresight from the earth limb (lower dashed line indicates 10 degree limb angle; upper dashed line indicates 30 degree limb angle).
  
  
• OBS: A bar showing the active observation, labeled with ProgramID:targetID:observationID, coordinates in degrees, target name, countrate and the skew wheel bias. The bias values are:
  
  • LN - Low Negative
  • LP - Low Positive
  • HN - High Negative
  • HP - High Positive
  
  
  
• SLEW, SLW, S/A, or ACQ: Spacecraft slews, labeled with the beta angle (B), pole angle (P), roll offset (R), and hemisphere of the attitude at the end of the slew (+ or - roll offset angle: + north, - south), speed of the slew (LO or HI), and the delay in seconds (D) from the beginning of the observation to the start of the slew. A bar is shown for any commanded slew, with the first black section indicating the length of the slew start delay, the white section showing the slew duration, and the next black section indicating the slew settle time. The black bar between the short vertical lines indicates an Acq or a "small slew" for, e.g. an offset Acq.
  
  Small slews and acquisitions. Acquisitions are labeled with the aperture (L - low, M - medium, H - high, R - reference point) and the acq_case. The acq_cases are as defined by the SCC/MP ICD:
  
  • 0 - No Acq (acquisition) performed
  • 1 - FUV (Far UltraViolet) Peak-up
  • 2 - FES (Fine Error Sensor) Target Acq and FUV Peak-up
  • 3 - FES Target Acq
  • 4 - FES Guide Star Acq
  • 11 - Unknown Star Acq
  • 12 - GS (Guide Star) Re-Acq
  • 15 - Offset Acq
  • 16 - Offset Re-acq
  • 18 - FES target correction only
  
  
• EXP: Exposures, labeled with the exposure ID above the block and the exposure type below the block (T - Time Tag, H - Histogram, F - FES (Fine Error Sensor) exposure, G - GNRA (Generic/Null Activity).
  
  
• SAA: Bars on this line show the calculated periods where the spacecraft is passing through the SAA (South Atlantic Anomaly). FUV (Far UltraViolet) observations cease during these periods. An indicator of the SAA model in use is sometimes also shown.
  
  
• OCC: Bars on this line indicate periods when the active target is occulted (behind the earth or below the earth limb threshold used for planning). If nothing is present on this line, the target was in the CVZ (Continuous Viewing Zone).
  
  
• TMX, NGT: This stands for "Terminator Crossing." Bars effectively indicate when the target is being viewed during orbital night. Blank regions are orbital day.
  
  
• GSP: Bars on this line indicate the positions of any ground station passes that occurred during the observation period. The passes are labled with the ground station involved:
  
  • UPRM - University of Puerto Rico at Mayaguez
  • TDRS - Tracking and Data Relay Satellite System
  
  
• TRQ: Torque authority intervals. A solid black line indicates that the target should be in the slit (i.e. no or very few losses of torque authority). A yellow interval denotes theta errors whose magnitude is up to 5 degrees (i.e. the spacecraft is "stable" but the target visibility is pretty unlikely). Larger theta errors correspond to red intervals (up to 10 degrees) and red crossed intervals (more than 10 degrees). Theta errors are angular deviations from the nominal pointing.
  
  
• HV: Bars on this line indicate periods when the detector high voltage is "ON".
  
  
• DV: Data Volume stripchart, showing how much memory is being used on the science data recorders. The nominal limit of 100Mb is indicated by the horizontal dashed line.
  
  
• MOM: Skew wheel Momentum stripchart. The nominal operating range in effect for the particular MPS is shown by the dashed horizontal lines. Discrete numerical momentum values are plotted and referenced by the "open circles" on the stripchart line.
  
  

Also shown on some of the plots are colored regions, and vertical lines. These indicate:

• Light Green: Visibility intervals (unocculted, SAA free times) during which FUV exposures can occur.
  
  
• Dark Green: Acquisition intervals indicate times when the acquisitions and re-acquisitions must occur.
  
  
• Pink: Periods when the "skew wheel axis to magnetic field" angle is suitable for skew wheel momentum unloading. A "filled circle" to the upper left of the pink region and an "unfilled circle" to the lower right of the pink region indicate times when the unloading is switched "ON" and "OFF" respectively.
  
  
• Red dashed line: (Vertical). Indicates orbital noon.
  
  
• Blue line: (Vertical). Boundary between discrete observations.

Parameter Combinations for MPSs

• YYYY-DDD: MPS numbers: Parameters
  
  
• 1999-203 - 2000-309: 001-222: RAM, LIMB, OBS, SLEW, ACQ, EXP, SAA, OCC, TMX, GSP
• 2000-313 - 2001-179: 223-282: OBS, LIMB, SAA, OCC, NGT, SLW, ACQ, EXP, GSP, DV
• 2001-181 - 2002-115: 283-344: OBS, LIMB, SAA, OCC, NGT, S/A, HV, EXP, GSP, DV
• 2002-120 - 2005-250: 345-533: OBS, LIMB, SAA, OCC, NGT, TRQ, S/A, HV, EXP, GSP, DV
• 2005-264 - 2007-262: 534-633: OBS, MOM, SAA, OCC, NGT, TRQ, S/A, HV, EXP, GSP, DV