(meteorobs) IMO-NEWS: Satellites to be "Sandblasted" by Leonid Storm

The Aerospace Corporation
El Segundo, California

June 8, 1998

Satellites to be "Sandblasted" by Leonid Storm

Dr. William H. "Bill" Ailor of The Aerospace Corporation told a
congressional subcommittee in Washington May 21 that the estimated 500
satellites on orbit "will be sandblasted" by the Leonid meteoroid storm due
November 17.

But he said the effects on spacecraft are expected to be minimal, despite
the fact the storm "will be the largest such threat ever experienced by our
critical orbiting satellite constellations."

Ailor, director of the Center for Orbital and Reentry Debris Studies
established last year at The Aerospace Corporation, presented his testimony
during a hearing titled "Asteroids: Perils and Opportunities." He was
invited to appear before the Subcommittee on Space and Aeronautics, a panel
of the House Committee on Science, by U.S. Rep. Dana Rohrabacher (R-Calif.),
subcommittee chair.

"It is possible," Ailor told the subcommittee, "that some satellites will be
damaged, but the most likely source of damage will not be from a rock
blasting a hole in a satellite, but rather, from the creation of a plasma,
or free electric charge on the spacecraft. The charge could cause damage to
computers and other sensitive electronic circuits on board the spacecraft,
and ultimately cause the spacecraft to fail. For example," Ailor said,
"during the 1993 Perseid meteor shower, it was determined that the Olympus
communications satellite was damaged by a meteor strike and went off the air
shortly thereafter as a result of an electrical failure."

Ailor pointed out that, "The latest information on the coming Leonid
meteoroid storm was presented at the Leonid Meteoroid Storm and Satellite
Threat Conference sponsored by Aerospace and the American Institute of
Aeronautics and Astronautics in Manhattan Beach, California, on April 27 and

"The primary recommendations from the conference," Ailor reported, "were
that, while it is very unlikely that the storm will have any major effect on
satellites, the 'A-team' of controllers should be on duty during
the ... storm, and operators should check the state of health of their
satellites frequently, looking primarily for electrical anomalies and
glitches. It was also recommended that, if possible, satellites be oriented
so that sensitive components are shielded from the oncoming stream of
particles, and that recovery plans be in place should there be a spacecraft
system failure during the storm."

Ailor said Aerospace collected information on spacecraft anomalies
experienced during the 1997 Leonid shower and will be collecting similar
information for the 1998 and 1999 events. "This information will help us
plan for the 1999 Leonid and future meteoroid storms. It may also help us to
understand whether additional safeguards against the meteoroid impact threat
should be included in future spacecraft designs," Ailor said.

Ailor's full testimony is on the Internet at http://www.aero.org/leonid/.

[NOTE: Dr. David Lynch of The Aerospace Corporation presented information on
this subject at a press briefing at the AAS meeting today. An image from the
AAS press briefing is available at

Dr. David K. Lynch of The Aerospace Corporation told reporters of the
potential threats to orbiting spacecraft by the Leonid meteoroids, expected
around November 17, 1998, and the mitigation strategies adopted by spacecraft
operators (June 8, 1998). AAS photo by Larry Marschall.]

Andrew Yee
ayee@nova.astro.utorontodot ca