Fast Auroral SnapshoT Explorer (FAST) Data Archive

The Fast Auroral SnapshoT (FAST), the second mission in NASA's Small Explorer
Satellite Program (SMEX), is a satellite designed to study Earth's aurora. This
highly successful spacecraft has helped scientists answer fundamental questions
about the causes and makeup of the aurora. FAST was launched on August 21, 1996
from a Pegasus rocket into a highly elliptical orbit. It crosses Earth's
auroral zones (donut shaped regions centered on the poles) four times each
orbit, and only collects high-resolution data ("snapshots") while in those
zones. It ventures high into the charged particle environment of the aurora to
measure the electric and magnetic fields, plasma waves, energetic electrons and
ions, ion mass composition, and thermal plasma density and temperature.

The electronics on FAST are programmed to collect data in an intelligent
manner. The data is used in real time to check for interesting events in order
to change to different sample rates, i.e. modes. The different modes are called
slow survey, fast survey, burst, and high-speed burst memory. For example, when
FAST passes over the auroral oval, the electron energy flux is enhanced,
triggering the electronics to change from slow survey to fast survey. Within
the auroral oval, burst and high speed burst memory modes are set when
triggered by events that might warrant further study, such as density cavities
or ion beams. Eight algorithms are used to determine what qualifies events
worth recording at burst rates. FAST can also be commanded by ground to use
different triggers for a given orbit.

FAST's scientific instruments are designed to conduct detailed studies of the
earth's aurora. They include the Electrostatic Analyzer (ESA), Electric Field
Sensors, Time of Flight Energy Angle Mass Spectrometer (TEAMS), and AC/DC
magnetometers.

Data collection is controlled by the spacecraft Instrument Data Processing Unit
and is stored on a 125 MByte solid state recorder and telemetered to ground
stations when they are in view. From the ground stations, the data is moved to
Goddard Space Flight Center in Maryland and then on to the Mission & Science
Operations Center at Berkeley, CA. FAST produces a prodigious amount of data
(nearly 1 terabyte in the first 2 years), so its archival is as automated as
possible.

FAST data consists of:
- electron plots
- magnetic and electric field data
- ion plots
- auroral kilometric radiation

See: http://sprg.ssl.berkeley.edu/fast/