MEIDEX Operational Philosophy

1
MEIDEX Operational Philosophy

• IAF
• Space Branch
• Major Meir Moalem

2
Problem

• Dust storms are random events
• So are sprites
• Abundance is different throughout the year
• ROIs are limited
• Airplane location - another constraint

3
Solution

• Define rigid ROIs
• Have a valid forecast
• Maximize observation opportunities
• Record every pass of ROI with sufficient lighting
• Additional degree of freedom (truss)
• Allow for flexibility in operational activation
• Collect a large sample of scientific data
• Define secondary, tertiary missions

4
General

• Aerosols backscattered light measurements
• Xybion multi-spectral camera, 6 W/L NIR to NUV,
  1410 FOV
• SEKAI CCD viewfinder, 60º FOV
• ADVCR digital recorders, 360 min total time
• Canister with 16" quartz window and HMDA
• Operated by PGSC WIN98 software
• Backup recording at the AFD (DSR-20)

5
The MEIDEX Payload
Upper support plates
Upper End Platew/ Quartz Window
Lens and Baffle
Gimbal Motor and Worm Drive
Optical Bench/Support
Bearing and Brake (both sides)
Worm Gear
Xybion Camera
SEKAI Camera
Avionics Mount Platew/ electronics
Lower End Plate
6
Operational Event Cycle

• Dust forecast
• Observation planning
• Where (if exists) is the dust plume?
• Where is the Shuttle?
• Where is the airplane?
• Secondary mission?
• Execute package
• Observation
• Astronaut (operations, backup, feedback)
• Quick analysis and re-plan

Fusion
7
Whos Who and Where

• TAU forecast center
• POCC
• Air Plane Base (Crete)
• Aeronet stations
• Sprites VLF stations

8
POCC Exp. Command Control
TAU forecast center
Med. ROI
Atlantic ROI
SPRITES
Global coordination in Real Time
STK scenario
9
Secondary Missions

• Sprites ionospheric TLEs
• Sea surface (Albedo)
• Slant visibility studies

10
Nominal (aerosols) Operations

• Bay-to-earth attitude, -ZLV directed to pass
  target (as forecasted), nadir view or a small
  bias
• Activate payload, use SEKAI for orientation
• fine tune truss pointing to dust plum (if
  possible)
• Record science data on MEIDEX canister and AFD
  (DSR-20)
• Monitor storm developments
• Supply ground planners with any useful
  information

11
Sprite Operations

• General convective forecasts, large possible
  areas (stk pic)
• Earth limb view attitude
• Tail (or nose) to earth
• Bay away from RAM
• FOV pointing above horizon
• Record lightning activity
• fine tune with truss

12
Execute Package

• Whats in it?
• Time of operations
• Location of targets (dust plumes, sprites)
• Location of airplane
• Forecast maps
• Payload related data \ instructions
• Any other remarks
• When will it be provided?
• 24H in advance
• 1-2 times per mission day / shift

13
Example Day 007

• Data from mission timeline
• 4 observational opportunities
• 2 dust, 2 sprites
• STK scenario
• Where is the shuttle?
• Where is the airplane?
• Define exact timeline for operation
• Ex. Pkg.
• Observation from space, monitor from ground
• Feedback? Changes between orbits

14
Back-up Recording

• Recording within the payload 360 min.
• Backup 1 DSR-20
• First to start recording, last to stop
• Used for playback to ground when no KU
• Backup 2 digital VCR at JSC, records playback
  orbits
• Backup 3 analog at GSFC
• Degraded quality, probably not sufficient for
  scientific analysis

15
Calibration

• Moon calibration
• Shuttle moon pointing maneuver
• Moon entering the Xybion FOV
• Maintain a 2-5 deg. Deadband for 10 min.
• Problem
• Alignment of experiment with the -ZLV
• Perform an alignment check on a pre-determined
  target

16
POCC Operations

• When
• A PS is not available
• Target of opportunities
• What is required
• Open the HMDA (the door)
• AFD recording
• Real-time video downlink

17
Anomalies

• Possible reasons
• Failures (use redundancy, camera definitions)
• Special scientific input (filter change)
• Pre-defined from ground in the Ex. Pkg.