Scientists and enthusiasts do not stop their attempts to hear or contact representatives of extraterrestrial civilizations. The most famous of these is the SETI project, which processes radio signals received from space. Every year astronomers record strange signals that require a scientific answer.
The fact that such projects are quite serious can be evidenced by the fact that in the period from the 1960s to the 1980s, SETI was secretly financed (through scientific funds) and was used by the CIA for space radio intelligence. Until now, there is no definitive evidence that someone tried to answer us or that we heard someone. Nevertheless, many strange signals came from the great void, the origin of which researchers are still trying to explain.
SHGb02 + 14a radio signal
The search for extraterrestrial intelligence, SETI @ home, launched in 1999, has attracted millions of personal computer owners to process the signals received by the Arecibo Observatory. The most hopeful thing was the radio signal SHGb02 + 14a, which arrived in March 2003. It was recorded three times and came from the region between the constellations of Pisces and Aries. True, the nearest stars in that direction are thousands of light-years from Earth.
X-ray signal in the Perseus Cluster
Promotional video:
Studying in detail the data obtained by the orbiting X-ray observatories Chandra (NASA) and XMM-Newton (European Space Agency), the researchers found an unexplained X-ray signal in the cluster of galaxies in the constellation Perseus. Scientists believe the signal is associated with dark matter (that is, matter that does not interact with electromagnetic radiation), which occupies 26% of our universe. Astrophysicists suggest that such X-ray radiation can occur during the decay of sterile neutrinos - a hypothetical type of neutrino that interact with ordinary matter only gravitationally. Some astrophysicists believe sterile neutrinos will help shed light on dark matter.
Black hole sound
The sound of a black hole was recreated by Edward Morgan of the Massachusetts Institute of Technology. To do this, he used data on the GRS 1915 + 105 star system in the constellation Eagle, discovered in 1992. It is the largest stellar mass black hole in our Milky Way. It is 14 (± 4) times heavier than the Sun and is located at a distance of 36 thousand light years from Earth. From a musical point of view, the radio noise from the black hole corresponds to the note "B flat", only 57 octaves lower than the "C" of the third octave. And people are able to perceive by ear only 10 octaves. This is the lowest note recorded in the universe.
Radio pulses at the Arecibo telescope
On November 2, 2012, the Arecibo radio telescope in Puerto Rico recorded a short radio burst similar to those recorded by Parkes. The researchers made calculations that showed that such impulses occur 10,000 times a day. Astrophysicists are now building new observatories and also using the power of telescopes in Australia, South Africa and Canada to understand why these radio signals are coming in so often and what they mean.
Fast radio pulses (FRB)
The nature of the bursts is still unclear - it must be something very powerful and compact, for example, colliding neutron stars, the collapse of a neutron star into a black hole, or a single burst of supernova energy before an explosion. Scientists joke that there are now more theories than known bursts. The power of such an event is very high - the same amount of energy is released in one second as the Sun produces in 10 thousand years. The brevity of the signal indicates the small size of the source, only about a hundred kilometers.