From Lori Stiles, UA News Services, 520.621.1877

(EDITORS: Note directions to field site and cell phone contact numbers at
the end of this story.)

A University of Arizona-led international team of 20 space scientists and
engineers this week are conducting an ambitious field test of equipment to
study dust devils swirling over the Santa Cruz flats near Eloy, Ariz.

The “Matador” experiment, led by Peter Smith of the UA Lunar and Planetary
Laboratory and funded by NASA’s Human Exploration and Development of Space
enterprise, will help define instruments needed for studying much larger
dust devils on Mars later in this decade, possibly in 2007.

Mars dust is a major potential threat to both robotic and human exploration
of the Red Planet. Enormous martian dust devils – 100 times larger than
those on Earth — churning tons of electrically charged dust particles could
cause lightning bolts and discharges that might fry computers and delicate
electronics, interfere with radio communications, or rip apart pressurized
human habitat.

Earth dust devils can be 10 meters to 20 meters in diameter and 1,000 meters
(a kilometer or six-tenths of a mile) high, Smith said. Mars dust devils are
typically a kilometer in diameter and 10 kilometers (6 miles) high. Martian
dust devils are so big that they dust the planet’s atmosphere, giving the
atmosphere its reddish-brown hue, and so big that Mars Global Surveyor
cameras have photographed them from orbit.

Smith, whose Imager for Mars Pathfinder camera returned a trove of famous
photos from the surface of Mars where it landed July 4, 1997, was among a
group of scientists who recently briefed the National Research Council on
hazards to humans on Mars. He also is co-investigator for Beagle 2, the
lander part of the 2003 “Mars Express” mission, Europe’s first mission to
the Red Planet.

“We are going to get experience in measuring the physical and electrical
properties of dust devils,” Smith said. “We want practice tracking dust
devils with LIDAR. And we may find that we’ll need to make measurements that
we haven’t thought about yet.”

Starting today (June 4), the Matador team will conduct daily operations near
plowed but uncultivated agricultural fields in desert near Eloy. Using LIDAR
at their fixed station, researchers will track speed and direction of the
moving dust storms, then drive their instrument-laden pickup “mobile
station” into the paths of any dust devils they can intercept. Video crews
in another vehicle and at the fixed station will record dust devils as they
hit the instruments deployed from the pickup.

LIDAR, which bounces a laser beam to measure distance to the dust storm,
will be used to track moving dust devils and get density profiles of dust in
the twisters. The suite of instruments for the field test also includes
cameras, a laser doppler anemometer for gauging wind speed, temperature and
pressure sensors, magnets, high frequency and low frequency radios and
electric field antennae, a dust counter, an “electric field mill” made by
Global Atmospherics of Tucson (it measures changes in Earth’s electric field
that averages around 100 volts per meter but shoots up to 2,000 or 3,000
volts per meter, e.g, during lightning strikes), and MAOS, the Mars
Atmospheric Oxidant Sensor, a chemistry experiment to discover the source of
oxidation (corrosion) on Mars. Portable GPS units are attached to the
scientists’ rugged field laptop computers.

Team scientists include Smith and others from the UA Lunar and Planetary
Lab; John Marshall of NASA Ames Research Center, an expert on dust
properties; William Farrell of NASA Goddard Space Flight Center, an expert
on the electrical properties of dust devils; Greg DeLory of the University
of California-Berkeley, who is managing the data system during the
experiment; Allan Carswell of Optech, Ontario, Canada, who will operate the
LIDAR; Barry Hillard of the NASA John Glenn Research Center, who will be
using the electric field mill; Nilton Renno of the UA departments of
atmospheric sciences and planetary sciences, an expert on Earth’s dust
devils, and others.

FIELD SITE: At 10 a.m. tomorrow, Tuesday (June 5), the team will leave the
UA campus from the Lunar and Planetary Laboratory loading dock, east of
Flandrau Science Center, drive I-10 to Eloy, turn south on Sunshine
Boulevard and drive 5 miles to a place noted as Friendly Corners on detailed
maps. There they’ll set up a tent to shade LIDAR and other fixed station


Lori Stiles, UA News Services, (520) 360.0574

Peter Smith, (520) 661.8040

Nilton Renno, (520)465.2594

Contact Information

Peter Smith

520.621.2725 (UA office)

Nilton Renno

520.621.6016 (UA office)