The last two 'traumatic' episodes in Space go back a few years: the latest was the collision between the Russian satellite Cosmos 2251 and the American Iridium33, in February 2009. Two years earlier, a Chinese antisat missile hit the Fengyun-1C weather satellite dead centre, causing it to explode: a somewhat “heavy handed” move by Beijing, which also proved to be a little clumsy, generating a huge amount of debris.Exactly 13 months later (so we are now in February of 2008) the United States "explained" - so to speak - to the Chinese that some things can be done in a much cleaner manner, destroying their spy satellite USA193 with a SM3 missile launched from the warship USS Lake Erie west of Hawaii. The secret? Americans hit their targets within 100 km from the earth: it is more difficult, but the debris created disappears in a matter of months due to the friction of the atmosphere. Thus far the news behind which lies the problem: only the first two collisions mentioned, have produced a debris mass of nearly 5 thousand fragments, bringing the total number of potentially dangerous fragments larger than 10 cm to over 19 thousand, zipping around the Earth at speeds of several kilometres per second and were built by man. Or rather, all that remains of objects constructed on Earth. All materials to which "natural" debris are added that wander in space and on the existence of which man has no particular responsibility.