There have been daydreams about aliens in ancient and modern times, but today humans can't actually detect whether there are aliens. Although many people have claimed to have witnessed aliens visiting the earth and even contacted themselves, most scholars and experts believe that the so-called different degrees of contact between human beings and aliens is actually a psychological effect, and the chances of human beings discovering "aliens" are very small.
In the search of the past 50 years, astronomers have not found any conclusive clues about aliens. As of 20 15, the scientific community generally believes that "life will only appear on planets around stars that can emit light and heat, but not all stars necessarily have planets".
Expanding Data Since the 1970s, human beings have been looking for the "neighbors" of the universe in various ways.
1974, the American radio astronomer Drake designed a special "telegram" with binary symbols, covering mathematics, physiology, astronomy and the general situation of the human body, and sent it to a cluster containing more than 300,000 stars-the globular cluster of the Milky Way.
1977, NASA launched Voyager 2 and? "Voyager 1" spacecraft, each carrying a record and a record player, records all kinds of information about the origin and development of human beings, and is called "Voice of the Earth".
On March 6th, 2009, the first kepler mission to search for Earth-like planets was launched from Cape Canaveral, USA. Scientists plan to explore about 654.38 million sun-like star systems in Cygnus and Lyra of the Milky Way in about four years, and search for exoplanets in the "livable zone".
Stephen Hawking believes that since there are about 654.38+000 billion galaxies in the universe, "it is reasonable to infer the existence of extraterrestrial life".
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