Mars Society 2004 RAC Presentation

1
Dust Devil Observations from the2005 MASST Field
ExperimentSeptember 19, 2005  
Brent J. Bosa, Bruce Gentrya, William M.
Farrella, Telana L. Jacksona, Stephen Metzgerb,
Joseph P. Comera, Jeremy Doblerc, Gerald S.
McIntirea, Catherine Neishd, Peter H. Smithd and
Robert Atlasa
aNASA Goddard Space Flight Center, Greenbelt,
MarylandbPlanetary Science Institute, Tucson,
ArizonacUniversity of Arizona Optical Sciences
Center, Tucson, ArizonadUniversity of Arizona
Lunar and Planetary Laboratory, Tucson, Arizona
2
Overview

• Mars Aerosol Sampler, Scanner and Tracker (MASST)
  instrument suite in development at GSFC
• Proof-of-concept (TRL 3) MASST instruments field
  deployed to make terrestrial dust devil
  measurements
• Eloy, Arizona
• June 6-11, 2005
• Evolution of 2001 and 2002 MATADOR work
• In-situ and remote sensing instrumentation
• Doppler lidar
• Visible cameras
• VLF Radio
• Electrometers
• Dust particle monitors
• Anemometors
• Thermometers
• Etc.
• Primary Goal Simultaneous dust devil
  measurement with full suite of instruments
• Requires coordination between instrument teams
• Imagers boresighted with Doppler lidar
• Multiple instruments on the same chase vehicle
• Two-way UHF radio and real-time GPS RF link
  between remote instrument base station and chase
  vehicles

3
Doppler Lidar Results
Dust Devil
Wind shear
Range (km)
Dust Devil
Range (km)
Dust Devil
4
In-Situ Instrument Results
Dust Devil Wind and Pressure Measurements at 5 m
Electrometer response Voltage vs. Time at 1.8 m
5
Notable Observations

• Phantom Vortex Event Observation of vortex
  essentially free of dust for a substantial
  portion of its lifetime.
• Doppler lidar, microphone and imager measurements
• Dust free for at least 5 minutes
• High translational velocity (12-15 m/s)
• Followed by sustained wind gusts
• A large, long-lived (gt30 minutes) dust devil was
  intercepted 4 times by chase vehicle and observed
  with Doppler lidar and imagers.
• gt150 mg/m3 dust density at 1.5 m
• Translational velocity of 4.7 m/s
• Review of data indicates there were likely 2
  other dust devils measured by both the in-situ
  and remote instruments.

Phantom Vortex

• FY06 Goals
• Field test large depth-of field particle image
  velocimeter
• Increase Doppler lidar dynamic range and rep
  rate
• Improve coordination between teams