China's ancient books, including Zi Zhi Tong Jian, also recorded the phenomenon of suspected UFOs. For example, The Chronicle of Emperor Wu of Han Dynasty records that "there is a sunrise day and night in April" and "there is a sunrise day and night", that is, something that looks like the sun appears at night, and the scientific view is a supernova explosion or a mirage.
Song Zhenzong Tianxi (10 18) In May of the second year, Sharla Cheung, the governor of Heyang (now mengzhou city, Henan Province), reported to the central authorities a strange thing that happened in his area, saying that someone in Xijing (now Luoyang) recently rumored to have seen a strange thing in the sky, shaped like a round hat, which often flew into the crowd at night and suddenly turned into a wolf.
The citizens in the city were frightened, so they closed the doors and windows at night and hid in hidden places. Because this monster is shaped like a "hat cover", people expect the meaning of "shape" and give it a rather vivid name "hat demon"
Extended data:
UFO phenomena can be roughly divided into four categories:
1, misunderstanding of known natural phenomena
2. Unknown natural phenomena
3. Unknown natural creatures
4. The fourth category refers to the aircraft with obvious intelligent flight capability and high performance that are not disclosed by the Air Force.
That is, some experimental disc flying machines that the air force has not disclosed. It can be seen that UFOs and alien UFOs cannot be equated.
Ufo and UFO can't replace each other. Like other phenomena, flying saucers can cause ufo events, but flying saucers themselves do not belong to ufo category, that is, they belong to ufo category before being confirmed as flying saucers, but do not belong to UFO category after being confirmed as flying saucers.
Baidu encyclopedia -UFO