September 16, 2000 – During the last decades, many studies have shown that at this stage of solar system evolution, considerable danger still exists from close encounters of Earth with minor space bodies: asteroids, comets and their fragments. Impacts from such bodies could cause local, regional or global catastrophes. Global catastrophes occur once every 100,000 to one million years; these are the most dangerous, with consequences ranging from degradation of the human race to its total elimination. Regional events, such as tsunamis caused by falls of large bodies into the oceans, have higher frequencies (1 every 10,000-100,000 years); they may cause the death of up to hundreds of millions of people and huge economical losses. Even local events, like the Tunguska explosion, may represent a severe threat. Such an event occurring over a large city causes the death of several million people and an economic loss comparable with the gross national product of some industrialized countries. These events occur about once every 100-300 years.

For the first time in history, we have reached a sufficiently high level of technology to cope with the danger, by finding the hazardous objects in space and by adopting measures able to prevent space impacts. The unanswered question is whether we, as a global society, are ready and willing to provide the resources necessary to preserve our safety, or whether we will postpone such a decision until the next disaster actually happens.

The inventory of dangerous objects is far from complete. Large asteroids with sizes greater than 1 km pose the greatest threat and are mostly visible from ground; in the last years their discovery rate has increased thanks to the efforts of researchers in the USA, but an international program must be put in place to monitor and study them. It is believed that about 50% of the population of largest objects has been discovered; this is expected to reach 90% completeness by 2010. However, it is desirable to implement an extended, international program for their physical characterization, including possible space reconnaissance missions. The gathering of all necessary information will give the opportunity to make appropriate decisions about the methods and technologies we might use to prevent the largest impacts.

The situation is more complex with regard to smaller objects. The number of medium-size objects (between 100 meters and 1 km) is evaluated to be around 100,000-200,000 and it is difficult, if not impossible, to catalogue them all using current technology. In order to prevent impacts from such objects another strategy should be used. We should identify those objects that are on a collision course with the Earth and mitigation technology should neutralize them when they approach the Earth within several million kilometers or less. To provide reliable and timely discovery of such objects it is necessary to have network of two or more ground-based middle-size large-field telescopes and one or two space-based ones. Ground-based radio locators could provide precise trajectory measurements. It is also important to develop exploratory missions for such objects to study their physical properties. The missions would represent the prototypes of future technological means for impact mitigation.

The participants to the Conference recommend to the Science Academies of Russia and Ukraine, the Russian and Ukrainian Space Agencies, the Russian Ministries for Atomic Energy, and for Extreme Situations to plan a national program of investigation into the hazards posed by impacts and develop systems for their mitigation.

The Conference also recommends that international efforts be coordinated along the aforementioned research lines, and international programs be created to discover, monitor, and explore these dangerous objects, in order to develop an impact prediction, mitigation strategies and technology.