Over the years, scholars ufologist, had to recognize two different types of UFO sightings: the soft UFO (or UFO light ) And hard UFO (or UFO sound ).
OVNI the so-called solid, have a extremely superior technology that is available on earth, and almost always metal, has been sighted in very different forms but generally circular , Oval or spherical. Its size can vary from a few centimeters to several tens of meters, but did not prevent him from reaching supersonic speeds , Turns to close, even to 90 ° (square) or even to remain stationary in the air and then again with unbelievable acceleration. The UFO is hard in most cases quite silent All the data collected suggest that these airplanes in a way not to be subjected to physical laws we know and therefore that his consistency is only apparent, but this possibility is contradicted by Physical tracks leave in case of landing, surveillance radar and more. We recall some of the most famous remains found following an alleged UFO landing:

• was rediscovered in 1954 in Florence called " Silica wool ", A compound of magnesium, silicon, calcium and boron;

• in 1957 to Utubia (Brazil) were found fragments of pure magnesium ;

• in 1954 in Campinas (Brazil) Dr. Maffei saw the presence of Residual metal pure at that time not available in any part of the world;

The soft UFO no obvious differences in shape and size than solid but seem to have the option of materialize and dematerialization , To act as fluids , Become transparent and even merge with other UFO tenuous. These effects were also found on creatures which occupy airplanes: they are reports of entities that will materialize and dematerialisation in a beam of light emitted dall'UFO, appearing in homes and cars suddenly and other similar phenomena. Data collected indicate that often the witnesses of the UFO phenomenon have come to light paranormal abilities (telepathy, precognizione, etc..).
Recently, the case has revealed that the second type of sightings are much more frequent than in the past: it seems that we are coming to " second phase "Dell'ufologia history.