Could “Alien Civilizations” Find Earth Through Radio Signals? | Science

Can you imagine cell phone towers sending massive radio signals into space? Could any alien civilization receive and decode these signals? Or is it just a faint echo in the fabric of the universe?

Cell phones rely on wireless transmission towers that cover large areas of the Earth’s surface and emit microwave signals all the time. Scientists have long wondered: Can “space civilizations” pick up these signals? And I tried study A recent study published in the journal Monthly Notices of the Royal Astronomical Society answers this question.

Accordingly For press release On May 2, 2023, the SETI Institute announced that researchers set out to study how radio signals streaming through space have changed.

In the 20th century, the majority of radio transmissions reaching space came from terrestrial radio and television stations. Now, the value of these signals has decreased, as military radar signals are becoming the strongest source of radio radiation leakage on the Earth’s surface, while cell towers are second in signal strength.

Terrestrial radio signal leakage

A team of researchers simulated and modeled the leakage of radio signals from cell phone towers to predict what a hypothetical alien civilization living on one of our nearest planets would receive.

“If alien civilizations were not more advanced than us, it would be difficult to detect the current level of leakage of radio signals from cell phone towers on Earth,” believes Ramiro Saidi, one of the researchers of the SETI Institute study. However, the team believes that some hypothetical alien civilizations may have receiver systems that are more sensitive than ours.

Mike Garrett from the University of Manchester, head of the research team, said: “In recent years many people have believed that there is less Earth noise in radio waves, which I have always rejected. Although we have fewer TV and radio transmitters today, mobile communication systems are very widespread in our world today.

Although each device in these cellular systems emits a small amount of radio waves, billions of these devices require integrated spectrum.

Prospects of Alien Civilizations

The group notes that each communication tower emits 100-200 watts of radio signal. Depending on the number of towers and the amount of radio leakage, this equates to several gigawatts sent into space.

If we assume that an alien civilization has advanced radio astronomy technology like our Event Horizon Telescope, our radio signals would be detected approximately 20 light years away.

According to Garrett, “According to current estimates, by the end of this decade we will have 100,000 satellites in low-Earth orbit and beyond. The Earth is already irregularly illuminated in this region of the radio spectrum. If this increase continues, it is too easy. Any advanced civilization must be explored with appropriate technology.”

Cell phone signals leaking from Earth interfere with certain messages in a way that aliens cannot distinguish. Any alien civilization could use these signals to learn some interesting information about Earth, such as determining Earth’s rotation and axis tilt. They can measure land distribution (by observing the distribution of signals over the Earth’s surface). They can study how the population distribution on Earth changes over time.

The team concludes, “We know a lot about the properties of exoplanets every day, thanks to space missions like Kepler and TES. We believe there is a great chance that there are advanced civilizations in space, some of which will investigate radio emissions produced by humans on Earth.”