Chemistry and Physics Faculty Proceedings, Presentations, Speeches, Lectures


The C-REX sounding rocket mission

Event Name/Location

2015 Coupling, Energetics and Dynamics of Atmospheric Regions conference in Seattle, Washington

Event Name

2015 Coupling, Energetics and Dynamics of Atmospheric Regions conference

Event Location

Seattle, Washington

Document Type


Publication Date


Date Range

21-25 June 2015


For reasons that are not well understood, there are permanent enhancements in the neutral mass density in Earth's thermosphere in the vicinity of the northern and southern geomagnetic cusps, and at altitudes of around 400 km. Such enhancements are expected to cause small but important and currently unpredictable perturbations to the orbits of spacecraft flying through them. Here we report on a NASA sounding rocket mission to study mechanisms responsible for establishing and maintaining these enhancements. On November 24, 2014, a Black-Brant 12 sounding rocket was launched from Andoya Space Center out over the Greenland Sea, and into the enhancement region associated with the ionospheric footprint of the northern geomagnetic cusp. It released ten rocket-propelled "grenades" that dispersed barium strontium tracer clouds into the thermosphere throughout a 3D volume extending over many tens of km around the main trajectory, and spanning heights from 190 to 400 km. Subsequent motions of the ionized barium and neutral barium/strontium components of the clouds were determined by photographic triangulation, using cameras based at Longyearbyen, Ny-Alesund, and aboard a NASA aircraft flying just south of Svalbard. Initial results of this analysis will be presented, and the implications for the mechanism(s) responsible for the density anomaly will be discussed.