Greetings mmatw!
Great question!
There are about 650 human-made satellites orbiting Earth. One
engineer estimates "that the chances of any one satellite getting hit
[by a meteor] range from 1 in 1 million to 1 in 10,000."
Hits do occur.
"In August 1993, during the Perseids, an Olympus communications
satellite was lost to a meteor hit. The impact formed a plasma cloud
that caused electrical discharges in the spacecraft and zapped its
attitude control system. By the time operators could stabilize it,
they had depleted all of its attitude control propellant and the
satellite was a loss."
above quotes from:
"NASA to help satellite operators watch ups and downs of Leonids"
http://science.msfc.nasa.gov/newhome/headlines/ast10nov99_1.htm
The above article also states:
"The only sure meteor protection for a satellite is to keep it on the
ground. But measures can be taken to mitigate the risks for those in
orbit. These include turning off all but the most crucial electronics
to reduce the risk of short circuits in case of an impact, and
pointing sensitive optics and solar arrays away from the Leonids."
The danger is not so much the actual impact that the meteor would
cause but instead it's the plasma cloud that is created by the impact.
"The [meteor] particle would vaporize when it struck, creating a
plasma ... This cloud of electrically charged gas could short-circuit
the satellite's delicate electronics".
"Leonids may short satellites"
http://www.nature.com/nsu/010927/010927-5.html
In the 1999 Leonid Showers, "military satellites came through
unscathed, while two civilian satellites were briefly disabled." The
two that were disables were affected by the effects of the plasma
cloud.
"The Leonid meteor shower"
http://www.csmonitor.com/durable/1999/02/03/p19s3.htm
From a CNN article:
"Some scientists say the odds of satellite damage are low.
'I think it is very unlikely that any major satellites will be
impacted by a meteor particle to the extent that it can no longer
operate,' said Donald Yeomans, an astronomer in NASA's Jet Propulsion
Laboratory. ... But scientists can't predict the risk posed by the
particles. The particles could poke holes in solar panels, pit lenses,
blast reflective coating off mirrors, short out electrical circuits
with a burst of electromagnetic energy or even reprogram computers,
said Edward Tagliaferri, a consultant with the nonprofit Aerospace
Corp. ...Military satellites are better off because they are built to
withstand a nuclear attack."
above text from "Meteor shower poses threat to Earth satellites"
http://www.cnn.com/TECH/space/9804/27/leonid.meteor/
"Satellites are designed with information about past storms and other
things that can happen in space ... Air Force controllers at Peterson
are responsible for monitoring the various constellations of military
satellite systems around the clock ... 'For the Leonids we have models
that help us predict when the storm will peak, so certainly (the
satellite operators) can be more attentive during that time, but we
monitor the spacecraft pretty vigilantly every day of the year,' ...
'I will not reveal anything operationally about any actions we might
or might not take.' </P>
above quote from "Earth Orbiting Satellites Brace for Leonid Meteor
Shower"
http://www.space.com/businesstechnology/technology/leonids_satellites_011107-1.html
http://www.space.com/businesstechnology/technology/leonids_satellites_011107-2.html
With regard to the International Space Station, the above article also
points that the ISS "has armor to protect it against stuff as much as
an inch across." So it sounds like the risk to the ISS is pretty
close to zero since meteors are usually much less than an inch across.
Unfortunately I live in an area that is completely covered by clouds
tonight so I'm not going to get to see any of the meteors. If you get
to head outside tonight enjoy the show for me.
I hope this information is helpful. If you would like for me to
clarify any part of my answer or further research your question,
please let me know before issuing a rating. Thanks!
leep-ga
some search strategies:
"Leonid Meteor shower" + satellites |
