Scientists have once again asked themselves how we can find a signal from an extraterrestrial civilization. This time, they noticed that Earth’s civilization emits powerful pulses precisely when it attempts to establish communication with its own spacecraft.
Signals in space
A team of American scientists searching for extraterrestrial intelligence recently published a study analyzing where and when it is best to look for radio signals coming from other intelligent beings.
The problem of searching for technosignatures, or technomarkers, in the form of artificial radio signals comes down to one fact that seems paradoxical at first glance. Although the Earth’s atmosphere seems to be overflowing with signals, most of them quickly weaken to such an extent that even the nearest stars require giant radio telescopes to detect them.
That is why it is much more likely to pick up a powerful directional signal. But the question arises: where will the extraterrestrial civilization inhabiting a planet near one of the millions of observed stars send it?
NASA as a source of inspiration
To get closer to solving this problem, scientists asked another question: when does humanity send out powerful radio signals? The answer is simple: when we send instructions to devices in deep space. For example, when controlling Mars rovers or the James Webb Telescope.
Researchers studied this issue in greater depth and determined the frequencies and duration of the radio signals. In fact, these pulses are not blocked by the surface of the planets, but continue to travel through space. And theoretically, someone could pick them up.
So, if you look at a system with several planets, the best time to search for signals is when two of them and Earth are aligned. Scientists have calculated that there is a 77% probability that the signal from our directed transmission to Mars has reached some planet in the last 20 years. The only question is whether anyone could hear it there.
The research team also determined that the average transmission of space communication systems could be detected approximately 23 light-years away using telescopes similar to ours. Focusing efforts, they say, on solar systems that are within 23 light-years, and especially those whose plane is oriented edge-on to Earth, could improve the search for extraterrestrial intelligence. The team now plans to identify these systems and quantify how often they could have received signals from Earth.
According to phys.org
