Aug 12, 1996
Scientists "de-SCIFER" Physicsof the Earth's Plasma Fountain
rocket, which flew in January 1995.
SCIFER, which stands for Sounding of the Cleft Ion Fountain Energization Region, carried two experiments from SSL designed to measure various plasma components in a particular region of the Earth's magnetosphere. The Cleft Ion Fountain is a plasma fountain that sprays plasma made from our atmosphere up over the poles and feeds the plasma storm process on the night side of the Earth. The SCIFER observations show that this region is richer in hydrogen plasma and depleted of oxygen plasma relative to earlier MSFC observations made from the Dynamics Explorer (DE) satellite. Scientists have attributed this result to a difference between high solar activity during the DE flight period and low solar activity during the SCIFER flight.
SCIFER also shows that the fountain heating or "energization region", has a very sharp boundary in the direction of the Earth's equator, only about 1 km thick. Furthermore, plasma in the energization region displays an inverse relationship between the density and temperature; where the temperature is high, the density is low, and vice-versa. This behavior is seen in both the electrons and the ions which make up the plasma. The physics involved in the heating region are not completely understood, however these are significant clues to the operative mechanisms of this heating.
A similar rocket payload named CAPER with two additional MSFC experiments has been selected for launch in early 1998 to further explore this region and better determine the mechanisms of heating.
sign up for our express news delivery and you will receive a mail message every time we post a new story!!!