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Elusive Meteor Storm Offers Last Glimpse

Centre for Research in Earth and Space Technology
Toronto, Ontario

Contact:
Andre Bellefeuille
Director, Communications
CRESTech
office (416) 665-5464, cell (416) 707-9120,
email: andre@admin.crestech.ca

Press Release - November 12, 1999

Elusive Meteor Storm Offers Last Glimpse

Toronto -- The debris of Comet Tempel-Tuttle, better known as the Leonid
Meteor Storm, is once again on Earth's radar screen for the night of November
17 and likely for the last time until roughly the year 2032.

The mysterious debris field is of great concern to scientists and satellite
owners. As Earth passes through the path of Tempel-Tuttle's highly elliptic
orbit, satellites within Earth's gravitational field will face their greatest
risk of physical damage since the huge Leonids storm of 1966.

The Centre for Research in Earth and Space Technology (CRESTech) is once
again leading a global observation and risk-reduction program to try and
build a comprehensive model of the Leonid meteor storm. Though the Leonids
only appear every 32-33 years, they offer immense insight toward building
forecasting technology that could help protect the world's satellite fleets
from similar astral activity.

CRESTech's clients for the 1999 program include the Canadian Space Agency
(CSA), the Department of National Defence (DND), NASA, the United States
Air Force Space Command (USAF) and the European Space Agency (ESA).

Last year's program surprised many scientists when instead of seeing a
massive quantity of "shooting stars," many viewers in the Far East were
treated to a show of large fireballs, few in number but highly visible. As
a result of travelling through a different "slice" of the meteor field, this
year's event is anticipated to result in massive quantities of shooting stars,
but few large fireballs.

Through the involvement of researchers at the University of Western Ontario
and other Canadian and international institutions, the CRESTech-led team
will set up electro-optical camps in Israel's Negev desert and the La Palma
Observatory on the Canary Islands, considered to be the two best viewing
points globally. Additional optical data will be collected by the USAF in
Florida, Hawaii and the Kwajalain Atoll. Radar data will be collected in
Northern Canada at a station in Alert, Nunavut.

A full backgrounder on the Leonids program is available at
"www.crestech.ca/leonids" as are links to NASA and ESA descriptions of the
event.

- 30 -

CRESTech is made possible through the Ontario government's Centres of
Excellence Program.

For more information, please contact:
Andre Bellefeuille
Director, Communications
CRESTech
(416) 665-5464, cell (416) 707-9120
www.crestech.ca

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Media Backgrounder - November 12, 1999

Statement of Problem

Many scientists believe that between 1998-2002 there may be a large,
transitory increase in the meteoroid hazard in the near-Earth space
environment resulting from the Leonid meteor shower. The Leonid stream,
which emanates from the constellation of Leo and orbits around the Sun,
has a 33-year travel cycle. It peaks over a three-to-five year time span
matching the period during which the parent comet (Comet Tempel-Tuttle)
travels closest to the Earth. Historically, there have been observations of
over 40 visible meteors per second to ground observer during the climax
of these storms. This peak period is normally preceded by a few years of
build-up, during which an indication of potential activity can be recorded
from the ground. This increase in activity is roughly 10,000 times the
norm and results in an accumulation equal to that of several years regular
activity in our skies.

There is a general consensus within the scientific community that some
enhanced activity will be realized due to the next shower, however useful
predictions are not possible due to limited historic data. During the last
major meteor storm, in 1966, satellites were much smaller and less
numerous than today. Today there are estimated to be between 600 and
750 operational satellites in Earth's orbit. While many space-faring
nations, predominantly the United States, have devoted considerable
resources to measuring and understanding "space weather" phenomena
caused by solar activity and other aspects of the space environment,
meteoroid activity has not figured prominently in this effort.

The hazards to spacecraft result not only from the large number of
meteoroids, particularly those of smaller masses, but from the high speed
of the Leonid meteoroids (72 kilometres per second). The effects of such
impact may range from infrastructure damage to the more serious threat
of electro-static discharge generated from such an impact. Such charges
could interact directly with a spacecraft's electrical systems and
essentially "short-circuit" the satellite. The latter effect has been
proposed as the likely explanation for the loss of ESA's Olympus
telecommunications platform in 1993. All satellites, both military and
civilian, at all orbital altitudes are at risk from this natural threat.

Extensive work has been performed by the University of Western Ontario
in London, Ontario, under the funding auspices of the Toronto-based Centre
for Research in Earth and Space Technology (CRESTech), to model the
physical processes resulting in the appearance of this storm. This
unique model allows for predictive capabilities so long as appropriate
observational data are available to constrain the initial conditions.
However, observational data is not yet sufficient to provide accurate
forecasts of the shower over the next five years. Observations made in
1997 and 1998 indicate that, and agree with, the recent discussions at
an American Institute of Aeronautics and Astronautics/Aerospace
Corporation Conference proposing that activity level may exceed as high
as 1,000 naked-eye observable meteors per hour.

The International Program

In 1997, the primary participants in the project were NASA, the United
States Air Force (USAF), the Canadian Space Agency (CSA), Canada's
Department of National Defence (DND) and CRESTech. In 1998 the same
partners were joined by the European Space Agency and Hughes Space
Corporation. With the increasing awareness of the Leonid threat, the
participants in the 1999 project are the USAF, NASA, CSA, DND, and the
European Space Agency (ESA).

Organizations participating in the operational portion of CRESTech's
program will receive real-time data on the storm's build-up rate, peak
and general activity. It is expected that these data will be used by some
satellite operators to take one of several courses of action in the event
that peak activity reach dangerously high levels. Among those actions are:
changing a spacecraft's attitude (i.e. pointing direction) to avoid being hit
in crucial or delicate areas; powering down an endangered spacecraft so
as to avoid a massive electrical discharge; or riding out the storm with
enhanced ground-station teams in order to react quickly to storm-
generated anomalies.

The 1999 Observation Campaign

Location: The two sites best suited for electro-optical observations
are the Israeli desert and La Palma Observatory on the Canary Islands.
Additional electro-optical data will be collected by the USAF at sites in
Florida, Hawaii and the Kwajalain Atoll.

Instruments: The 1999 campaign will employ two methods of data
collection: radar and Low-Light-Level Television (LLTV) observations.
Both are capable of measuring the smallest meteoroids (which are the
population relevant to the space hazard) and each can be used to establish
their physical parameters. The Israeli site will host two LLTV sites (each
with approximately five camera), and the La Palma site will host one radar
site as well as one LLTV site (with two cameras).  The radar data will be
collected at Alert, Nunavut in Northern Canada.

Science Team: The CRESTech science team includes Dr. Jim Jones, Dr. Alan
Webster, Dr. Kerry Ellis, Dr. Robert Hawkes, Ms. Margaret Campbell and Dr.
Peter Brown, who acts as the project manager. This represents the largest
group of meteor specialists in the world with a most varied list of
strengths. Dr. Hawkes (Mount Allison University, Sackville, NB) is the
world expert in application of video technology to meteor observations
and heads the LLTV component of the program working along with Ms.
Campbell (University of Western Ontario). Drs. Jones, Webster and Ellis
(CRC Ottawa) are world leaders in meteor radar systems, observations and
analysis. Dr. Brown (UWO) has studied and adapted models of the stream
and liaise with the satellite community in an effort to understand satellite
effects of the storm. No other single group has the equivalent breadth of
scientific expertise in this field.

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Links:

* European Space Agency's Leonids site
  http://www.esoc.esa.de/pr/esoc.topics/1999.11/leonids/leonids.php3

* NASA's Leonids site
  http://www.leonids99.com/
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For more information on the CRESTech program, please contact:

Andre Bellefeuille
Director, Communications
CRESTech
office (416) 665-5464, cell (416) 707-9120,
email: andre@admin.crestech.ca


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