Feb. 2007

Third Deployment of PUMA :
In December, Linnea Avallone’s group participated in the third deployment of the PUMA (Plume Ultrafast Measurements Acquisition) project, sampling the exhaust of the shuttle Discovery (STS-116) shortly after launch from the NASA WB-57F aircraft. The field team included graduate students along with other colleagues from CU and Boulder company Droplet Measurement Technologies. PUMA piggybacks on the WB-57 Ascent Video Experiment (WAVE), a NASA Marshall project that tracks the shuttle launch using HD-TV camera technology.

This launch was particularly challenging for the WAVE and UMA projects because it occurred at night (about 9 pm local) prior to moonrise, requiring extra efforts on the part of the aircraft pilot. With information we supplied from the ground based on a trajectory model, pilot Bill Ehrenstrom was able to find the remnants of the shuttle exhaust plume (at 60,000 ft altitude) nearly 20 minutes after launch in complete darkness. We sampled the plume twice, recording data on water, carbon dioxide, particulate and ozone amounts. These are the first data obtained in a shuttle plume in the dark and will allow us to show definitively that the stratospheric ozone loss associated with shuttle launches is the result of photochemistry (i.e., requires sunlight).

PUMA plans to take to the air again for the March launch of Atlantis on STS- 117.