SETI’s ‘Noah’s Ark’ – a space historian explores how the advent of radio astronomy led to the USSR’s search for extraterrestrial life

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As humans began to explore space in the second half of the 20th century, radio waves have proven to be a powerful tool. Scientists could send radio waves to communicate with satellitesrockets and other spacecraft, and use radio telescopes has capture radio waves emitted by objects throughout the universe.

However, sometimes radio telescopes would capture artificial radio signals from telecommunications. This interference threatened sensitive astronomical observations, causing inaccurate data and even damaged equipment. While this interference frustrated scientistsit also sparked an idea.

During the Cold War, a a new domain has appeared at the intersection of radio astronomy and radiocommunications. He put forward the idea that astronomers could search for radio communications from possibly existing extraterrestrial civilizations. Astronomy is generally discussed observe the natural phenomena of the universe. But this new field has made the detection of technologically or artificially produced substances radio wavesobject of a natural science.

This area has continued today and is now called the search for extraterrestrial intelligence, or SETI. SETI encompasses everything scientists do to search for intelligent life beyond Earth. It includes one of the original uses of radio telescopes: studying signals from across the galaxy in hopes of detecting intelligent messages.

When the idea behind SETI was first proposed and pursued in the 1960s, only two countries, the United States and the USSR, had the technical capabilities. As the only space powers at the time, they were the main players affected by radio interference.

As a historian of scienceI worked to make sense of what happened throughout the history of Soviet SETI during the space race by analyzing a series of primary sources. SETI captured the scientific imagination of many leading Soviet astronomers in the 1960s and early 1970s.

Astronomers have yet to confirm any detection of radio signals – or any other type of signs – extraterrestrial civilizations. But many scientists continue to search, even if their bold ideas run into obstacles. Some evidence suggests humans could be the only intelligent life in the universe.

Soviet SETI: The Golden Age of Radio Astronomy

SETI is closely linked to the profound changes brought about by radio astronomy. Until the second part of the 20th century, scientists could only see astronomical objects and phenomena. in optical or visible light. Optical light is the same type of light that the human eye is sensitive to.

After World War II, scientists realized that they could peacefully use radar antennas, developed for that war, to detect radio signals from objects in the universe. Deciphering these signals has allowed researchers to study astronomical objects in the universe. For example, they discovered the most abundant element: hydrogen.

In the former Soviet Union, the eminent pioneer of radio astronomy Iosif Samuilovich Shklovsky played a key role in detecting radio signals emitted by hydrogen.

Scientists knew that each chemical element would absorb certain wavelengths of light and reflect others, and the light signals that an object absorbed or reflected could tell astronomers which element it was. Most hydrogen couldn’t be observed directly in optical light, so astronomers didn’t spot it in space until they began looking beyond the visible light spectrum.

Shklovsky understood how to detect hydrogen with radio waveswhich helped astronomers map the distribution and movement of hydrogen gas within and between galaxies.

Historians generally consider the year 1960 to be the beginning of the golden age of radio astronomy. After hydrogen was detected, astronomers discovered previously unknown types of stars, such as pulsars and quasars. These phenomena have offered scientists new insights into the nature of astrophysical phenomena and fundamental physics.

Shklovsky later became fascinated by the possibility of using radio waves to contact other intelligent beings in the universe. In 1960, he published an article on this subject in one of the most prestigious scientific journals in the country.

Shklovsky’s article quickly developed into a very popular book called “Universe, Life, Intelligence“, published in 1962. In the same year, the USSR Academy of Sciences sent his first radio message towards Venus from a radar in Crimea.

The experience involved bouncing radio signals off the surface of Venus transmit the following words in Morse code: Lenin, USSR and mir, which in Russian means both world and peace. Even if the risk of radio interference increases statistically, this message was above all symbolic. The Soviet Union wanted to show off its technological power and did not expect to communicate with extraterrestrials. Soviet SETI was therefore not yet a real pursuit.

Start an organized search

Shklovsky and the majority of other radio astronomers pursuing extraterrestrial intelligence were all in central Russia at the time. The USSR Academy of Sciences was also located there. But this group needed more formal steps to move its research from a few initiatives to a coordinated effort.

Due to concerns about unwanted public attention, scientists organized a conference far from Moscow, at the Byurakan Astrophysical Observatory in the Soviet Republic of Armenia, in 1964. At this conference, researchers formed a group specifically dedicated to the study of artificial radio signals from space. With this group, SETI became a top-down, state-directed activity.

With this validation, scientists could now theoretically look for artificial signalspotentially of extraterrestrial origin. However, any discussion of artificial radio signals was subject to strict government oversight, given that military satellites also depended on them.

Soviet scientists encountered several obstacles. For example, the secrecy of their own government made coordination difficult. The Cold War too set limits on the international development of SETI. However, they had the green light to search for and study particular signals that they suspected were of artificial origin.

International collaboration

International collaborative efforts on artificial signals culminated in 1971 with a conference, still in Byurakan. There, about 50 scientists – the majority from the United States and the USSR, but also some from Czechoslovakia, Hungary, the United Kingdom and Canada – agreed on the best way to conduct SETI.

Some presents compared this gathering to Noah’s Arkas an almost equal number of eminent scientists from the east and west of the Iron Curtain managed to meet that year. And the gathering took place in Armenia at the foot of Mount Araratlocated in neighboring Türkiye. It is on this mountain that archaeologists believe Noah’s ark could have ended up.

After almost a week of discussions in Byurakan, the two geopolitical blocs designated an official SETI group. This group still exists today and still connects researchers around the world who conduct SETI research. Given the secrecy surrounding radio signals in space, this international SETI group marked a momentous diplomatic achievement at the height of the Cold War.

SETI began in the Soviet Union with some strong initiatives based in Moscow. This continued through group events in Armenia – from the first Soviet state-level conference to the international conference.

SETI is the first and only field of astronomy to study artificial radio signals itself. It indirectly dealt with radio frequency interference at a time when these frequencies were very unregulated.

Stakeholder countries have finally resolved their radio interference problems with international agreements on the use and allocation of radio frequencies. An international committee approved a feasible and comprehensive radio frequency allocation plan for the first time in the 1970s. This plan has since been revised and renewed. Today, space scientists and astronomers use a internationally agreed plan to minimize this interference.

It is remarkable that SETI began even before this allocation plan. SETI continues its rich legacy today in continue to look for signals – and along the way, discover new objects and astrophysical phenomena.

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