PUBLIC INFORMATION OFFICE
JET PROPULSION LABORATORY
CALIFORNIA INSTITUTE OF TECHNOLOGY
NATIONAL AERONAUTICS AND SPACE ADMINISTRATION
PASADENA, CALIF 91109 TELEPHONE (818) 354-5011
http://www.jpl.nasa.gov

Contact: John G. Watson

FOR IMMEDIATE RELEASE
May 12, 1997

JPL WEB SITE FEATURES IMAGES OF EARTH'S IONOSPHERE

      Images of the Earth's ionosphere as it changes in response to solar activity are now available at a new web site managed by scientists at NASA's Jet Propulsion Laboratory.

The site address is http://sideshow.jpl.nasa.gov/gpsiono/press.html

      Informative, color-coded global maps are updated every hour, 24 hours a day. On April 10-11, during a major solar flare, images were updated every 15 minutes, resulting in the first-ever real-time publication of global images of the Earth's ionosphere as it rapidly changed during a major geomagnetic storm.

      Within a few days of the April disturbance, additional information on the site included more complete global electron content maps and analysis, revealing such major storm features as: the doubling of electron content in the initial phase of the storm, followed by depletions; the presence of steep gradients in content that can distort short-wave communications paths; and the global distribution of ionospheric irregularities (small-scale structures that can severely disrupt radio communications).

      The continuously updated information was based on ionospheric data extracted from transmissions of the Department of Defense (DoD) Global Positioning System (GPS) satellites. The site, opened in early April, is funded by the National Science Foundation, in cooperation with the University of Michigan's Space Research Laboratory.

      The site can serve as an important resource for astronomers, weather forecasters and others involved in atmospheric science, for the impact of future storms will be mapped as they happen and made available to all via the Internet.

      Dr. Ulf Lindqwister, supervisor of JPL's GPS Networks and Ionospheric Systems Development group, explains, "Space storms, caused by large eruptions on the surface of the Sun that catapult charged particles toward Earth in a cloud of magnetized gas can have significant impact on expensive advanced technology systems operating in or communicating through space. Mapping on the JPL web site will provide critical information for operating those systems, thus playing an increasingly important role in future space weather monitoring operations."

      The JPL unit originating the site is the Telecommunications Science and Engineering Section, whose sponsors include the DoD, the Office of the Pentagon, the Air Force's 55th Space Weather Squadron and the U.S. Navy.

For further information, call Lindqwister at (818) 354-1734.

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