Localized height profiles of neutral winds and wind gradients derived from drifts of vapor tracers released during the AWESOME rocket mission.

The large-scale global behavior of wind and temperature fields in Earth’s
thermosphere is now reasonably well understood, as a result of decades of
observational and modeling studies. However, superimposed on these
background dynamical fields are much more localized perturbations
associated with propagating acoustic gravity waves. Global descriptions are
unable to resolve local gradients, which are defining characteristics of wave
perturbations. Magnetic storms and substorms deposit energy and momentum
into the atmosphere through Joule heating and ion drag. This deposition is
effective at exciting waves because the resulting gradients occur on spatial
and temporal scales commensurate with requirements for waves that can
propagate at thermospheric heights. This work focuses on characterizing
gradients established by a magnetospheric substorm. The in situ absolute
measurements of wind presented here allow us to resolve spatial gradients on
scales inaccessible to typical remote sensing techniques.
For this mission, three sounding rockets were launched from Poker Flat. Each
allowed wind measurements by releasing optically trackable vapor clouds.
The first rocket was launched on March 25, 2025, just after the onset of a
substorm. It released a quasi-continuous trail of tri-methylaluminum (TMA),
from which height profiles of wind were obtained over altitudes spanning 80
km-160 km. The second rocket was launched an hour later. In this case, 20
tracer clouds (12 TMA and 8 Ba/Sr) were deployed in a 3-dimensional
constellation by sub-payloads ejected at ~100 m/s from the main vehicle
earlier in the flight. The purpose of this constellation was to allow
measurement of all nine first-order spatial gradients in the wind field. The
third, launched during magnetically quiet conditions on March 29th, 2025,
released another vertical TMA trail and was used to provide a baseline
measurement of the quiet time wind field. The position of the tracer clouds
was determined through photographic triangulation using images obtained
from multiple ground-based sites. Wind velocity measurements were then
derived from the motion of these tracer clouds over time.
This poster presents wind velocity profiles derived from tracer drifts and, from
variation between these profiles, the resulting 3-dimensional view of the
localized thermospheric wind gradients