The team of researchers analyzed 21 galaxies with high levels of radiation in the mid-infrared range. To their surprise, they found that four of these galaxies had their radiation amplified by a factor of 10.
Two of them were explained by natural processes, while the other two remained unexplained.
Two distant galaxies could be home to highly advanced alien civilizations. Traces of unusual activity have been found in both galaxies, which may indicate the presence of an alien civilization of type III on the Kardashev scale.
One of humanity’s deepest and most important questions is “Are we alone in the universe?”.
The deeper we look into the universe, the more galaxies we discover. According to the numbers, as of 2022, researchers estimate that there are more than two trillion galaxies in the observable universe.
In our understanding of the cosmos and the number of galaxies that have arisen since our universe began 13.7 billion years ago, the Hubble Space Telescope is of paramount importance.
One of the deepest images of space is the so-called Hubble eXtreme Deep Field. This image revealed the dimmest and most distant galaxies ever seen and allowed experts to look further into the past than ever before.
But even with this photograph of about 5,500 galaxies, we are far from understanding the number of galaxies in our universe.
Are we alone in the universe? Although this question cannot be answered with certainty today, we may be close to finding it out.
Researcher Honging Chen and his colleagues at China’s National Astronomical Observatory scanned part of the northern sky. Their goal was to see where exactly in this area there are signs of hyper-advanced alien civilizations.
Of the 21 galaxies they examined, two galaxies stood out with anomalous characteristics.
Their results were presented in a study published in the Monthly Notices of the Royal Astronomical Society.
Traces of advanced alien civilizations?
The universe is truly gigantic. Given various factors, such as the age of the universe, the number of stars and galaxies, it would be presumptuous to consider the Earth to be the only planet where life originated.
Perhaps somewhere in a distant galaxy, not so similar to the Milky Way, a civilization arose that developed over millions of years and surpassed even our greatest achievements in terms of technology.
To understand how advanced a potential alien civilization might be, we use the Kardashev scale, developed by astrophysicist Nikolai Kardashev in 1964.
It allows you to measure how technologically advanced a hypothetical extraterrestrial civilization is, based on the amount of energy it consumes. The scale includes three types of civilizations:
Civilizations of the first type
This is a potential civilization that is technologically advanced enough to use all the energy of its home planet.
Civilization of the second type
This potential civilization could harness the energy of the entire solar system, its sun and planets.
Type III Civilization
This potential civilization has reached such a level of technological development that it can use the energy of the entire galaxy.
A civilization of the third type can easily use the many stars of its galaxy as energy sources by building hypothetical megastructures called Dyson spheres. By doing so, a civilization could harvest all the energy produced by a star.
Thus, by using thousands, rather than millions, of stars in its galaxy, a Type III civilization could meet its growing energy needs, which would allow it to evolve further and explore the universe.
If a Type III civilization placed Dyson spheres around many of its stars in its home galaxy, we could probably find traces of them.
This prompted Chen and co-author Michael Garrett to use the 2-meter LOFAR Two-meter Sky Survey (LoTSS) to look for any infrared signal that would indicate the presence of these megastructures.
They combed through 21 galaxies with high mid-infrared emission. To their surprise, they found that four of these galaxies had a 10-fold increase in emission.
“Two of them have been identified as natural sources – one was an active galactic nucleus and the other a star-forming galaxy, which means that their excessive mid-infrared emission results from different mechanisms,” says Chen.
“We don’t know the reason for the high mid-infrared to radio ratio of the other two.”
According to InVerse, radio and infrared emissions from each galaxy correlate with each other. The radiation of galaxies transmits information about its heat through the infrared spectrum. As part of their search for what looks like alien exhaust, the duo have been investigating the mid- and far-infrared spectrum, Chen explains.
A Type III civilization will produce excess mid-infrared radiation due to mid-infrared waste heat, which will affect the correlation.
Of the 21 galaxies, two stand out and are possible host galaxies for type II alien civilizations. In both galaxies, the researchers were unable to understand what caused the burst of radiation in the mid-infrared region.
While alien civilizations may be the culprit, other natural explanations cannot be ruled out, such as an unusually high rate of star formation or an extremely bright galactic core.
The galaxies ILT J134649.72+542621.7 and ILT J145757.90+565323.8 are likely to be analyzed in the near future. In their paper, Chen and his colleagues conclude that both galaxies “deserve further study.”
Whether these galaxies are home to powerful and advanced alien civilizations remains to be seen. Future studies of galaxies and observations in various spectra may help us answer one of the greatest questions that our species has so far been unable to answer.