Red and white vapor clouds filled the skies over the Marshall Islands as part of NASA's Equatorial Vortex Experiment (EVEX). The red cloud was formed by the release of lithium vapor and the white tracer clouds were formed by the release of trimethyl aluminum (TMA). These clouds allowed scientists on the ground from various locations in the Marshall Islands to observe the neutral winds in the ionosphere.
The EVEX was successfully conducted during the early morning hours on May 7, 2013, from Roi Namur, Republic of the Marshall Islands. A NASA Terrier-Oriole sounding rocket was launched at 3:39 a.m. EDT and was followed by a launch of Terrier-Improved Malemute sounding rocket 90 seconds later. Preliminary indications are that both rockets released their vapor clouds of lithium or trimethyl aluminum, which were observed from various locations in the area, and all science instruments on the rockets worked as planned.