Template for MTP 3rd Quarterly Review

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Particle Charge SpectrometerMIDP Mars
Instrument Development Program Workshop
Stephen Fuerstenau July 21, 2004
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Particle Charge Spectrometer
Description Goals

• Develop and field-test a rugged, low-power
  instrument for characterizing electrostatic
  charge on individual particles with Terrestrial
  and Martian applications.
• Extend particle measurements to a previously
  unobserved level of charge with a 10,000-fold
  improvement in sensitivity over earlier
  instruments.
• Investigate electrical phenomena caused by
  wind-blown dust in terrestrial Mars analog
  environments to expand the science rationale for
  deployment of the PCS measurement capability on
  Mars.

Funding Profile (K)

• Principal Investigator
• Dr. Stephen Fuerstenau JPL 384
• Phone [phone]
• Stephen.Fuerstenau_at_jpl.nasa.gov
• Co-Investigators
• Dr. Gregory Wilson JPL 322
• Dr. William Farrell - GSFC

FY03-FY04 Critical Milestones FY03 Reduce size
of PCS electronics package FY04 Field studies
with PCS and E-Field meter in terrestrial Mars
analog environment
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FY04 Milestones

• Demonstrate PCS pump operation at Mars
  atmospheric pressure - Q1
• Design and fabricate PCS Inlet Manifold Q2
• Demonstrate PCS operation at reduced pressure
  Q2 - Q3
• Conduct field tests with PCS and E-Field
  instruments Q2 Q3
• Demonstrate PCS operation with Rocky 8 rover Q3
• Organize Science Workshop on Electrostatic
  Environment of Mars - Q4

4
Significant Event

• Low Pressure testing of PCS and Pump
• Demonstrated required pumping rate for miniature
  diaphragm pump at low pressure
• Identifies a candidate low-power pump that can be
  used for PCS operation on Mars
• Preliminary demonstration of PCS operation at
  reduced pressure
• Indicates that PCS can detect charged particles
  under Martian conditions. May require
  modification of inlet geometry to accommodate
  full range of expected particle sizes (1 -100 mm)

5
Significant Event

• Size Reduction of PCS field unit electronics
• Achieved an 8-fold reduction in the volume of the
  PCS electronics unit and a four-fold reduction in
  mass.
• The new unit allows testing in the field and
  deployment on aircraft or balloons. These tests
  will augment the science rationale for the
  instrument

6
Significant Event

• Created improved inlet manifold
• Inlet houses a porous wall cylinder that allows
  for a variable dilution of the sample aerosol
• The inlet manifold allows the PCS increases the
  maximum concentration that the PCS can sample by
  a factor of 20, and improves the resolution of
  particle size measurement.

7
Significant Event

• Tested E-Field sensor with PCS in relevant
  environment
• Observed spikes in the vertical electric field
  that are associated with high count rates
  detected by the PCS during Santa Ana winds on
  Mar. 9 at JPL
• Data at right, while uncorrelated, confirm that
  the concentration, particle size, and charge
  magnitude of dust clouds can be recorded along
  with induced deviations of the electric field.
• Similar data sets for dust devils will be
  captured with the PCS and E-Field sensors from
  JPL and GSFC this summer.

8
Significant Event
Dust Devil Chase Boulder City , NV June
2004
GSFC Particle Sensor On Metzger Dust Devil Rig
JCI 140 Fieldmeter
Fieldmeter PCS
PCS in cooled housing
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Results from Boulder City, NV June 2004
PCS Data
Positive Field from Dust Devil 800 V/m
Negative Field from Dust Devil - 3400 V/m
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Plans for Next Quarter

• Perform additional field measurements on dust
  devils in Mojave desert
• Calibrate inlet manifold with aerosol generator
  at Caltech
• Complete test at low pressure and model particle
  gas interaction to better understand effect of
  low gas density on size measurement
• Demonstrate PCS operation with Rocky 8 rover
• Organize a workshop on electrostatic environment
  of Mars to raise interest in related fields
  within the planetary science community

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Financial Summary