By definition a phenomenon is considered unexplained when no kind of logical or scientific reasoning has come to say or to identify the causes, effects and nature. On the total number of observations, in percentage terms, the phenomena are explained in a fairly substantial number. This is to say that a fact or an event is inexplicable and so elusive to the understanding of science, it is necessary to verify that it is not a phenomenon Natural perfectly explicable. Here are the percentages hundred cases carefully analyzed:

• 90% , Perfectly natural phenomena explainable ;

• 5% Phenomena fully unexplained due to the current state of our knowledge;

• 5% , Totally inexplicable phenomena attributable to phenomena UFO proper.

Before you check the accuracy of these estimates statistics, researchers in the Blue Book Commission, made reference to the period 1947-1969: 320'000 observations of unusual phenomena in the U.S., 288'500 (90.15%) of which were explained while 31'500 (9.84%) cases have not found an explanation. After a careful analysis of these, only 14'500 ( 4.5% ) Observations were of the UFO phenomena as such. Clearly 90% of cases (as explained) are due to a layman observer who believes that he saw an unknown object. For example, in certain weather conditions, some planets are very bright and can be easily confused with UFOs. This is because observing, for example, Venus, Mercury or Jupiter atmospheric layers through an observer may have just experienced the feeling of seeing a ball or spot light shining. Other similar cases are frequent cloud-shaped disc, aircraft, lightning and bizarre behavior from rockets or satellites falling into the atmosphere. It is therefore essential to check the credibility of a witness.
To assess the reliability of an inexplicable phenomenon ufologist the following three criteria:

1. The phenomenon must be observed in good condition ;
2. The audit report should provide sufficient information to draw a successful conclusion the reality of the phenomenon;
3. The data from this conclusion does not result in no logical explanation or scientific .

If these three conditions occur we have a UFO phenomenon. To ensure that these three conditions are present you should follow a method with the utmost objectivity, the lack of which has up to now increasingly discredited the credibility of these phenomena at the common people. Here are the various processes to develop an accurate analysis:

1. Putting together the data collected and perform a reconstruction on site;
2. Interrogate all the witnesses influence and without obtaining their comments;
3. Examine methodically the facts observed, referring to the many relationships comments past , Comparing those who reported similar facts and interpreting them according to current knowledge ufologist;
4. Establish Conclusions The ratio of study;
5. The conclusions of the issue hypothesis .