Boston, Mass. -- Penn State researchers are analyzing data collected during a six minute rocket flight to better understand the ionosphere and how global change might effect that area of the atmosphere.
The flight, which took place on November 5, 1997, from Andoya Rocket Range near Andenes, Norway, lifted a variety of instruments into the ionosphere. Some of these instruments, like the nose tip probe that measures electron density from which temperature can be inferred and the electric field sensors that measure the electric field in three dimensions around the rocket, are repeats of experiments previously launched by members of Penn State's Communications and Space Science Laboratory.
"There are some experiments that are done repeatedly on every rocket and generally there are new experiments," said Dr. Timothy J. Kane, assistant professor of electrical engineering. "All these measurements are tied to ground-based observations."
The researchers, who include Kane, professors Charles Croskey, John D. Mathews and John Mitchell and research engineer, Timothy Wheeler, all of electrical and electronic engineering, are looking at the atmosphere 60 miles above the ground. They are specifically interested in the sodium there.
The sodium layer is part of the remnant of elements formed when meteors and meteorites enter the atmosphere and begin to burn up or ablate. These elements remain in the lower part of the ionosphere and form layers, but little is known about these layers.
The rocket payload included an instrument that measured the sodium atoms using a sodium vapor lamp that provided a single wavelength of light that is absorbed by sodium. The light's energy is then re-emitted, giving the researchers a way to measure the density.
The preliminary results of the November flight were presented today in a poster by Andrew J. Gerrard, graduate student in electrical engineering, at the spring meeting of the American Geophysical Union meeting in Boston. The aim of this research is to determine if and when sodium can be used as a tracer of atmospheric motion and to understand the relationship between sodium and sodium ions in the atmosphere.
"Sodium can be measured from the ground, and has been studied for years, but this is the first in situ measurement of sodium," says Kane. "We are also interested in how electric fields influence the sodium."
The CSSL (Combined Sodium and Sporadic Layers) payload collected data twice per millisecond during the six minute trip and sent the information to a ground station. This data is being analyzed to characterize the motions of the sodium layer.
"If we understand the way the layers move and change with change in temperature and electric field, we will better understand the basic dynamics of that part of the ionosphere," says Kane.
Current models of global change predict that the effect will be larger in the upper atmosphere. They suggest that a 1 degree Celsius change in the lower atmosphere will be equivalent to 10 degrees Celsius in the upper atmosphere.
"If the upper atmosphere really is more sensitive to global warming, then we should be able to see changes more there," says Kane. "However, to do that, we need to truly understand the dynamics of the atmosphere to see any changes or disturbances."
The CSSL flight was funded by and coordinated with NASA who supplied the rocket and the telemetering equipment at their Wallops Island Flight facility.
EDITORS: Dr. Kane may be reached at 814-863-8727 or tjk7@psu.edu.