Threat to Satellites from Leonid Meteoroids to be Examined

EL SEGUNDO, Calif. (1/19/98) -- The Aerospace Corporation's Center for Orbital and Reentry Debris Studies (CORDS) and the American Institute of Aeronautics and Astronautics (AIAA) will host in April 1998 a conference to examine the threat to satellites posed by upcoming Leonid meteoroid storms.

Titled the "Leonid Meteoroid Storm and Satellite Threat Conference," the meeting will be held April 27-28, 1998, at the Marriott Hotel, Manhattan Beach, California.

The purpose of the event is to provide information to satellite owners and operators about risks associated with the 1998 and 1999 Leonid storms, expected to be the most severe meteor showers in 33 years.

The last major Leonid storm occurred in 1966 when fewer than 100 satellites were in orbit. Now nearly 500 operational spacecraft are on station. They form the infrastructure for worldwide communications and navigation, as well as Earth- and weather-monitoring capabilities.

All Issues to be Addressed

According to CORDS Director Bill Ailor, Ph.D., the conference will address all issues associated with meteoroids and the threats they pose to government and commercial satellites. Such areas as hypervelocity impact phenomenology, orbital dynamics, system response, and possible actions spacecraft owners and operators might take to minimize potential damage will be discussed.

In addition, the effect on satellites of the November 1997 Leonid storm will be presented. The 1998 and 1999 storms are expected to have a significantly greater impact than the 1997 event because of the number of meteoroids anticipated.

If predictions are accurate, all satellites in orbit will be hit by Leonid meteoroids. Fortunately, according to Ailor, most are expected to be smaller than 0.3 millimeters in diameter and will not cause serious damage.

Types of Damage Possible

But Ailor said that spacecraft struck by meteoroids of significant size can incur damage of many types depending on circumstances: solar panels and optical surfaces can be pitted; plasma jets from the impact site can cause electrostatic discharge, especially if the spacecraft carries a differential surface voltage; and electromagnetic pulses, which might cause internal electronic failures and other problems, can be formed. Catastrophic puncture and shock wave damage can also occur if the meteoroids are large enough, though they rarely are, Ailor said.

Several satellites have been seriously damaged by meteoroids in the past. In 1993 the European Space Agency's Olympus satellite was hit by a Perseids meteoroid and lost attitude control. In 1991 the sun filter on Japan's SOLAR A satellite was punctured, ending its mission. Space station MIR and the Hubble Space Telescope were dinged in the 1993 shower.

Committee Members

Members of the organizing committee include Aerospace astrophysicist David K. Lynch, Ph.D., who will serve as technical chair; Edward C. "Pete" Aldridge, Jr., Aerospace president and CEO; Lt. Gen. Roger DeKok, commander, USAF Space and Missile Systems Center; Donald Cromer, president, Hughes Space and Communications Company; Gen. Bernard Randolph USAF (ret.), special assistant to TRW Space and Electronics Group; Charles E. Leontis, vice president, Mission Success and Product Assurance, Lockheed Martin Missiles and Space; Gary Davis, Director of Satellite Operations, National Oceanic and Atmospheric Administration; and W. John Hussey, Principal Scientist, Space Technology Applications, Aerospace.