Launch of MINIS test balloon at McMurdo Station, Antarctica
On December 15, 2003
the MINIS (MINIature Spectrometer) test balloon
was launched from Williams Field, McMurdo Station Antarctica.
This was an engineering flight to test a suite of small
instruments, the flight control computer, and an Iridium
modem-based telemetry system.
Test flight altitude profile
March 2004: analyzing test flight data and building new
The MINIS test flight was launched at 17:40 UTC Monday
December 15, 2003 (local time 10:40 AM Tuesday December 16, 2003).
The payload mass was about 40 kg and was carried by a 500,000
cubic foot helium balloon. The goal was to lift the payload
to 30 km altitude where it would ride winds westward around
Antarctica for about 5 days and collect data.
In the plot at left, time units are hours after payload
power was applied. Launch is at 1 hour.
After ascending through the tropopause to about 14km
the balloon failed and quickly descended. The payload landed
on Mount Discovery where it was dragged for some hours by the huge sail
of the balloon. Eventually, enough parts
broke off that the balloon-payload combination became buoyant,
and it rose from the mountain.
That this data is present demonstrates the
telemetry system, GPS receiver, flight computer, and power
system continued to work after the unexpected descent and
dragging episode. The aspect magnetometer, sun sensors, x-ray
spectrometer, and temperature sensors also continued to
function. Other instrument data is still being examined.
Neither the balloon nor payload were recovered.
More data from the test flight will be available from this page.
Download x-ray spectra (5MB pdf)
Download payload rotation data (340KB pdf)
Download temperature profile (530KB pdf)
Notes on the MINIS project
The MINIS project is an effort to understand the size,
frequency and mechanisms of relativistic electron
precipitation from the magnetosphere into the ionosphere. It
is the next step in an ongoing effort. The MINIS approach differs in
emphasis and method from its predecessor experiment
A different instrument package, which includes electric and
magnetic field sensors, will look for electromagnetic
indications of magnetospheric waves which might be
responsible for scattering relativistic electron out of
their repetitive motions in the magnetosphere and down into
Earth's atmosphere. The MINIS campaign will employ 4 balloons with
staggered launches in order to extend the longitudinal range
over which relativistic electron precipitation is observed.
These balloons will be hand-launched by graduate students from the
South African Antarctic station, SANAE, in January 2005.
University of Washington is contributing electric field
instrument components (Bob Holzworth and Michael Kokorowski)
and x-ray spectrometers (Michael McCarthy and Erin Lay)
to the balloon payloads. Michael Kokorowski will also
travel to SANAE to launch the balloons.