Will extraterrestrial civilization exist? This is a topic worthy of our thinking and research. Logically speaking, the possibility of the existence of extraterrestrial life and extraterrestrial civilization is relatively high. After all, the universe is really too big. There are countless exoplanets and . Even within our solar system, there are many potential planets with life. , such as Mars, Titan, Europa and other celestial bodies have many conditions for nurturing life. If the origin of life on Earth is not a specific thing, but appears naturally or randomly, then there should be an origin of life similar to Earth on an alien planet with a relatively superior environment, or something completely different from Earth. The origin of life.
In view of this situation, many scientists believe that extraterrestrial life, aliens, and extraterrestrial civilizations exist. For example, British scientists once calculated that there may be at least 36 active intelligent civilizations similar to the Earth in our Milky Way galaxy. These active alien civilizations may also use radio signals to communicate like us humans. Since radio signals have unparalleled advantages, they propagate very fast and over very long distances, so the communication between us and those distant interstellar ships is also achieved through radio signals. At the same time, scientists also use radio signals to search for extraterrestrial life and extraterrestrial civilization. Because when these potential alien lifeforms and alien civilizations use radio signals, some radio signals may "escape" into the depths of the universe. We might find these radio signals when we search the universe with devices like radio telescopes.
"Eye in the Sky" received a signal from a suspected extraterrestrial civilization
Speaking of advanced radio telescopes, I believe everyone knows about the Arecibo radio telescope and our 500-meter aperture radio telescope "Eye in the Sky". Now the Arecibo radio telescope has already exploded. Collapse, while our "Eye in the Sky" is operating normally. Because the "eye in the sky" has a very large aperture and very high sensitivity, it can receive weak signals from the depths of the universe. Among the weak signals received, some are suspected to be sent by extraterrestrial civilizations. How is this going? Did the "Eye in the Sky" really detect signals from alien civilizations? No wonder Wu Xiangping, an astrophysicist and academician of the Chinese Academy of Sciences, expressed his belief in aliens during the live broadcast of the Chinese Academy of Sciences' 2022 New Year's Eve speech. So is the radio signal discovered by the "Sky Eye" a call from an alien civilization?
Professor of the Department of Astronomy at Beijing Normal University and chief scientist of China's search for extraterrestrial civilization Zhang Tongjie said that their team used China's "Sky Eye" to discover several narrow-band electromagnetic signals that are different from the past. These signals come from outside the earth. , may be a candidate signal for extraterrestrial civilization. If the source of these signals can be confirmed and the content of these signals can be identified, it may be a sensational discovery. This may really be a radio signal sent by an alien civilization. If this can be confirmed, it means that the alien civilization is Yes, we humans are not alone.
Some scientists have also questioned this finding. For example, Dan Welheimer, chief scientist of the Center for Extraterrestrial Civilization at the University of California, Berkeley, believes that the suspicious signals received by our celestial eye are likely to be signals from the earth, not from aliens. Zhang Tongjie's team also believes that the suspicious signal is very likely to be some kind of radio interference. It is normal for
to have different opinions. After all, we have only received these signals so far and have not yet accurately confirmed the source of these signals. Scientists have previously received many radio signals from the depths of the universe, some of which were considered "suspected" signals from alien civilizations. However, some signals were eventually confirmed to be caused by interference from our human radio signals.
Because in daily life, we cannot do without radio signals. For example, our mobile phones, computers, TVs, satellites , radar and other electronic devices may produce some radio signal interference, which may be interfered by the Sky Eye or other radio telescopes. received. Since these man-made radio signals are very different from naturally occurring radio signals deep in the universe, we can still distinguish whether they are technologically generated radio signals or natural ones, but it may not be so easy for us to distinguish whether these signals are What humans send out is also sent by alien civilizations deep in the universe.
Earth may be exposed?
Seeing that scientists continue to discover radio signals from the depths of the universe, some friends may be worried that the earth may have been exposed. Because our human radio signals have also reached the depths of the universe. As early as more than 100 years ago, humans began to use radio signals to transmit information. In other words, the earliest radio signals used by humans may have traveled more than 100 light-years away. If there is an alien civilization within this range that has reached a certain level of development, theoretically they may receive human radio signals.
In addition to these radio signals that are inadvertently transmitted to the depths of the universe, scientists have also actively launched some radio signals into the depths of the universe. For example, in 1974, when scientists celebrated the completion of the renovation of the Arecibo radio telescope, they launched a Arecibo message consisting of a total of 1,679 binary digits. The target of this signal was about 25,000 light years away from the earth. The distant globular cluster M13. Scientists believe that if there are advanced intelligent civilizations in this galaxy cluster , then in theory they can receive our signals and know some basic conditions about the earth and human beings.
When scientists emit radio signals into the depths of the universe, they indeed cause many people to worry, because if they are intercepted by advanced alien civilizations, we humans may be exposed to them. Of course, some people think this worry is unnecessary. Because the farther the radio signal propagates, the lower the intensity. The intensity of the radio signal that can be emitted in front of us humans is actually very low. It may be too weak to be received by the time it reaches the edge of the solar system, let alone hundreds of people. Intercepted by alien civilizations light years or tens of thousands of light years away. Moreover, the radio signals we emit are not continuous, but very few signals are emitted. In other words, when this signal is transmitted to a certain planet, if the alien civilization of this planet does not detect the signal in time, it will miss the signal forever. So, we don't need to worry too much about this issue.
