Nanjing (CNS) -- Observers across the country captured images of an unidentified flying object (UFO) at around 9 p.m. on Saturday.
Several flight crews flying above Shanghai reported that they had spotted a light cluster in the air, while astronomy fans took photos of the "bubble-like object" in suburban Beijing.
Similar observations were reported in Inner Mongolia and Shanxi. The object was described as "a luminous body that expanded gradually into the shape of a ball several hundred times the size of the moon. The scene lasted 20 minutes until it finally faded out and disappeared."
Wang Sichao, a researcher at the Purple Mountain Observatory of the Chinese Academy of Sciences, told CNS Tuesday, "This is a significant UFO occurrence. A UFO is a special spacecraft which is hard to explain with man-made aircraft knowledge. The spacecraft was flying slowly in outer space, at roughly the same height that Yang Liwei (the first Chinese sent to space) reached."
With over 40 years of research experience, Wang Sichao gave two criteria for a UFO occurrence: it must be detected by a certain number of people at various places at the same time, and it is hardly explainable through current scientific knowledge.
"In the some 40 years of my study, 20 UFO occurrences were recorded. I concluded a rule that in years that ends with '1', '2' or '7', the rate of such an occurrence is the highest. This year happens to be 2011."
Other astronomers suggested that the phenomenon may have been caused by the unbalanced drive of a boosting rocket, or by substances emitted by military devices or satellites.
Wang denied the guess:"In the photo taken by the Hebei Station of the National Observatory from the west angle, the elevation angle of the spherical light cluster could be calculated according to the stars behind. The object could be located with the data of the two places where the UFO was observed."
"My analysis indicates that the spacecraft was flying slowing 300 km above the west Inner Mongolia. The speed of a man-made aircraft has to reach 7.9 km/s in order not to fall onto the ground. A craft at such speed can only stay in the same visual spot for several minutes. The fact of 20 minutes is beyond existing science."
