Chasing Dust Devils for
Science
Storm chasers are generally interested
in finding and photographing major storms, especially
tornadoes and associated weather phenomena. Some storm
chasers have secured scientifically important images
and data about tornadoes.
A much smaller atmospheric whirlwind
is of increasing scientific interest. This is the dust
devil, a column of rapidly spinning air that forms a
visible column that can reach a kilometer or more into
the sky.
Dust storms and dust devils occur on
both Earth and Mars. Thus, these natural phenomena provide
an interesting and scientifically important research
subject for the amateur scientist.
There is a very practical reason for
such studies, for new findings about the electrical
properties of dust devils are of great significance
to manned missions to Mars, where dust devils are far
larger than those on Earth. More data is needed about
dust devils before a manned mission to Mars. To better
understand why, consider this narrative by science writer
Trudy E. Bell about a fictional encounter with a Martian
dust devil:
"This was no little Arizona desert
whirlwind, only a few tens of meters high and a few
meters across and past you in seconds. No, what hit
you yesterday was a monster column towering kilometers
high and hundreds of meters wide, 10 times larger than
any tornado on Earth. Red-brown sand and dust whipping
around faster than 30 meters per second (70 miles per
hour) dropped visibility to zero, scouring your faceplate,
driving dust into every fold and wrinkle of your spacesuit.
For 15 minutes you huddled and endured the buffeting.
The scariest part was the incessant crackling and flashing
of miniature lightning bolts nipping at you and your
rover, and the loud static on your radio that prevented
you from calling for help." (The
Devils of Mars: When humans visit Mars, they'll
have to watch out for towering electrified dust devils,
Science@NASA).
Dust devils could become the target
of serious amateur scientists who reside where they
often occur. Fascinating technical details about electrical
measurements made near and inside dust devils can be
found in an online scientific paper by W. M. Farrell
et al. (Electric
and magnetic signatures of dust devils from the 2000–2001
MATADOR desert tests, Journal of Geophysical
Research 109, E03004, doi:10.1029/2003JE002088,
2004). This paper includes various kinds of measurements,
diagrams and photographs. It also includes important
references to previous research and points out the need
for more.
Important concerns about the possible
effects of giant Martian dust devils on future astronauts
and missions are described in a NASA report, "An
Analysis of the Precursor Measurements of Mars Needed
to Reduce the Risk of the First Human Mission to Mars."
Chasing dust devils along remote desert
roads is not nearly as risky as chasing tornadoes. It's
also lots of fun. It's sometimes possible to anticipate
the path of a dust devil well enough to park a vehicle
directly in front of its path in order to measure the
effects associated with its passage.
Amateur scientists who acquire photographs
and electric field and other measurements inside dust
devils will find that The Citizen Scientist
will give high priority to publishing their findings.
Forrest M. Mims III 
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