Our Earth is surrounded by a huge “bubble” of space debris. If you look at the map depicting all the man-made objects that are now in orbit, it becomes clear that we do not have two or three pieces of rockets or satellites flying over our heads. Why, there’s just a huge dump up there! This rather sad fact pushed astronomer Hector Sokas-Navarro to an interesting idea, which he shared with the readers of the scientific publication Astrophysical Journal.
Navarro works at the Institute of Astrophysics in the Canary Islands and studies the Sun most of the time. The more satellites appear on the Earth’s orbit, the more opaque becomes this very “bubble” of debris and operating spacecraft. The scientist suggested that technologically advanced aliens who entered the space age will also first send many spacecraft and satellites into orbit, which form a belt that can leave a mark on the light curve of the parent star during transit.
Surrounding the planet, Garbage Navarro called the Clarke belt and conducted a series of studies according to which a 10-meter telescope working in the infrared range is quite capable of registering artificial debris around Proxima b (if any). The same telescope can see Clark’s belt around most of the TRAPPIST-1 planets – TRAPPIST-1d, -e and -f.
But with planets similar to Earth, everything is not so simple. If it rotates around a star similar to the Sun, modern instruments will not be able to discern traces of extraterrestrial civilization around it. Considering the pace of development of modern technologies, sufficiently advanced telescopes capable of this will be able to detect Clark’s belt in the orbit of another planet similar to the Earth, in 200 years, not earlier.
The only problem with discovering aliens in this way is that space debris can easily be confused with the natural rings surrounding a potentially inhabited planet. But Navarro is confident that follow-up observations will help to distinguish one from another, and the studies of the planet itself can help in solving the problem.