The UCB auroral sounding rocket program designs, constructs, and launches small, solid fuel multi-stage sounding rockets to altitudes of up to 1400 km above the northern aurora to study particle acceleration and wave production relevant to auroral dynamics. The Earth's aurora is a circular region of intense electron precipitation encircling the northern polar cap, and the optical emissions seen from the ground are the result of the collisional excitation of nitrogen and oxygen as high energy electrons (1 - 20 keV) impact the upper atmosphere at about 100 km altitude. Ultimately the energy for this process flows from the solar wind into the Earth's magnetosphere, but exactly how this process occurs is still one of the unanswered questions in auroral physics. The goal of the sounding rocket program is to uncover the plasma micro-physics behind electron and ion acceleration and the role of the various plasma wave modes commonly observed above the visible aurora.
Left: A UV image of the Earth's aurora as seen by the Dynamics Explorer satellite. The bright circle denotes the region of particle precipitation and is seen in the visible spectrum from the ground as East-West greenish and sometimes red bands or "arcs".
Right: A photograph of an auroral arc taken by S. M. Ashford, graduate student at the Space Sciences Lab. The picture was taken from a remote observation post on the north coast of Alaska during the last rocket campaign in February 1993.
A schematic showing a sounding rocket trajectory through the plasma
processes above the visible aurora, where particle acceleration and
plasma waves are occurring. The vehicle is spin-aligned with the
rocket axis along the Earth's magnetic field as it proceeds in a
parabolic trajectory through several auroral arcs. The booms and
particle instruments are deployed after attitude alignment to take
measurements of waves and particle distributions. A standard
complement is 6 to 8 electric field probes to measure 3-D waves and DC
fields, electron and ion electrostatic analyzers, and a fast electron
spectrograph to resolve the field-aligned electron fluxes.