COUNCIL
OF EUROPE
Parliamentary Assembly
Resolution 1080 on the detection of asteroids and comets
potentially dangerous to humankind
-
There are two broad categories of
space objects which have the potential
to impact our planet: comets and
asteroids. They are generally known among
planetary scientists as
Near-Earth Objects (NEOs). Their total population
is unknown, but the
number of Earth-Crossing Asteroids with sizes larger
than about 1 km is
estimated to be about 2000. These objects are the most
dangerous and
only a tiny fraction of them have been detected to
date.
-
Considering that the explosion close to the Earth's
surface of even an
object with a diameter of 50 m can have the effect
of a 10 megaton nuclear
weapon, the consequences of larger impacts
would be disastrous on a global
scale. The best known, recent examples
are the Tunguska explosion of an
NEO about 60 metres in size (over
Siberia in 1908, resulting in the destruction
of over 2000 square km of
largely-unpopulated forest) , and the violent
impacts into Jupiter
of the fragments of comet Shoemaker-Levy 9 (in July
1994); those
fragments were only about 0.5 km in size, but caused devastation
over a
larger area than that of the Earth. Traces of other smaller impacts
on
our planet are frequently being discovered, as well as fossil
records
of cataclysmic impact events in the past.
-
The
significant amount of information gathered over the last few years
on
asteroid and comet collisions indicates how they can trigger
large-scale
and large-standing ecological catastrophes, sometimes
leading to mas s extinctions
of species; thus such impacts represent a
significant threat to human civilisations.
-
Although,
statistically speaking, the risk of major impacts in the near
future is
low, the possible consequences are so vast that every reasonable
effort
should be encouraged in order to minimise them.
-
The Assembly
therefore welcomes various initiatives - i.e. the Spaceguard
Survey
report published by NASA, the creation of the Working Group on
Near-Earth
Objects by the International Astronomical Union, and the
recent decision
of the NEO community to set up a Spaceguard Foundation
to coordinate the
efforts at an international level - as important
steps paving the way towards
the development of a world-wide
surveillance programme aimed at discovering
all potentially-hazardous
NEOs and tracking their orbits forward by computer
so that any impact
could be foreseen some years in advance, allowing preventive
actions to
be taken as necessary.
-
The Assembly invites governments of
member states and the European Space
Agency (ESA) to urge the
setting-up and development of the above-mentioned
Spaceguard Foundation
and to give the necessary support to an international
programme which
would:
-
establish an inventory of NEOs as complete as
possible with an emphasis
on objects larger than 0.5 km in
size;
-
further our understanding of the physical nature of
NEOs, as well as the
assessment of the phenomena associated with a
possible impact, at various
levels of impactor kinetic energy and
composition;
-
regularly monitor detected objects over a
period of time long enough to
enable a sufficiently-accurate
computation of their orbits, so that any
collision could be predicted
well in advance;
-
assure the coordination of national
initiatives, data collection and dissemination,
and the equitable
distribution of observatories between northern and
southern
hemispheres;
-
participate in designi detected from
the ground, and for investigations which
can most effectively be
conducted from space;
-
contribute to a long-term global
strategy for remedies against
possible
impacts.
Strasbourg, March 20,
1996
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