SPACE: Dust Clouds (fwd)

Mark Grant (mark@unicorn.com)
Fri, 18 Jul 1997 13:02:33 +0100 (BST)


A couple of weeks ago someone was asking about the Earth passing through
dust clouds in space. Here's the Risks article I mentioned (from Risks
Digest 19.23)... should be exciting:

Date: Thu, 26 Jun 1997 01:36:23 -0400 (EDT)
From: Jonathan Nash <jnash@qis.net>
Subject: 1998-1999 Leonids may damage satellites

An article in the 9 Jun 1997 issue of *Science News* warned that the Leonid
meteor showers in 1998 and 1999 may damage satellites. The Leonid meteor
shower occurs around the middle of November and usually 100 meteors an hour
may be visible. In the Far East in 1998, 100,000 meteors an hour may be
visible. In 1999 there will also be a very heavy Leonid shower in Western
Europe.

"A Leonid storm occurs every 33 years, when Earth passes through the
meteoroid storm shortly after Temple-Tuttle has neared the sun and spewed
fresh particles. On 17 Nov 1998, Earth will hit the Leonid stream just 9
months after the comet has passed closet to the sun. In that short
interval, the torrent of new meteoroids won't have had time to spread out.
Our planet will encounter a dense swath of debris, creating a veritable
tempest.

"The dust particles are tiny, so chance collisions with spacecraft aren't
the prime worry of scientists. Rather, researchers express concern about the
potential of these particles to create localized clouds of electric charge,
or plasma, that can penetrate satellites and short-circuit equipment.

"The high speed of a Leonid meteoroid - about 72 kilometers per second, more
than three times that of an average meteoroid - favors the production of
clouds of charged material, notes Brown. These can generate lightninglike
discharges inside satellites, zapping fragile electric components.

"Another meteor storm, this one associated with a swath of cometary debris
known as the Perseids, is credited with taking a satellite out of commission
in 1993 (SN: 2 Oct 1993, p. 217). However, the potential for damage is highly
uncertain... Come 1998, 'everyone is going to go through this test, whether
they like it or not.'"