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