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The Petrozavodsk jellyfish: the dawn light show that launched Soviet UFO research

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In the early hours of September 20, 1977, a jellyfish-like light showering beams onto the city appeared over Petrozavodsk, and it was also spotted from Helsinki. The Soviet press called it an “unidentified natural phenomenon,” and a year later the Academy of Sciences launched a state research program. In the West, the likely cause was identified within days: a satellite launched from a secret military base.

When: September 20, 1977
Where: Russia
Witnesses: hundreds of residents, port workers, paramedics, police officers, meteorologists; also seen around Leningrad and in Helsinki
Official position: In 1977, the Soviet press called it an unidentified natural phenomenon. The leaders of the Soviet state UFO research program (Academy of Sciences and Ministry of Defense, 1978–1990) later attributed it to the launch of Kosmos-955 from Plesetsk.

4 a.m. in Karelia

In the early hours of September 20, 1977, many residents of Petrozavodsk, the capital of Soviet Karelia, were still asleep. Those who were awake saw something extraordinary. Nikolai Milov, the local correspondent for the TASS news agency, described it this way: at around 4 a.m., a huge "star" suddenly flared up in the dark sky, sending pulsing shafts of light toward the ground. The "star" moved slowly and silently over the city, spread out like a jellyfish, and showered the houses with countless thin rays that looked like pouring rain.

After a while, the rays stopped. The "jellyfish" turned into a bright semicircle and moved toward Lake Onega, whose horizon was covered by gray clouds. A semicircular gap then opened in the cloud cover, bright red in the middle and white at the sides. According to witnesses, the whole event lasted 10 to 12 minutes.

According to Milov's memoir, the witnesses included crane operators at the river port, sailors on watch aboard local shipping company vessels, night-shift workers at the tractor plant, paramedics, meteorologists, police officers, and border guards.

"It cannot be called a mirage"

In the TASS report, Yuri Gromov, director of the Petrozavodsk Hydrometeorological Observatory, said the staff of Karelia's weather service had never seen anything like it. Weather stations had recorded no sudden atmospheric changes. Gromov added that no technical experiments were being conducted in Karelia or on the Kola Peninsula at the time. Nor could the event be dismissed as a mirage, he said, because it had many witnesses who, from different parts of the city, largely described the same thing.

Vladimir Krat, director of the Pulkovo Observatory near Leningrad, told TASS that the observatory's astronomers had also seen a fireball crossing the sky from south to north over the Leningrad region and Karelia that morning. According to Krat, its origin could not yet be determined.

According to Milov, Finnish newspapers also reported a glowing ball over Helsinki at around 4:06 a.m. Moscow time.

A news story that was pulled

According to Milov's memoir, published in 2010, the story went out on the TASS teletype network on September 22, and the newspaper Sotsialisticheskaya Industriya ran it on September 23. However, the head of TASS ordered the text withdrawn on the day it went out, so only a few newspapers printed it. The news still reached other countries: on September 24, the French daily Le Méridional reported on an unidentified natural phenomenon observed in the Soviet Union.

An English translation of the TASS text is also among the CIA documents released years later.

A string of explanations

Soviet scientists offered one explanation after another, but none named the real cause:

On October 12, 1977, Krat said the phenomenon was probably caused by the burning remains of an artificial satellite reentering the atmosphere.
In August 1978, chemist N. Dmitriyev spoke of a chemiluminescent zone created by nitrogen oxide emissions from Petrozavodsk's factories.
In 1979, academician Vladimir Migulin pointed, in the French journal La Recherche, to an unusual combination of atmospheric, magnetospheric, and solar conditions.

Solved in the West within days

Western news reports caught the attention of James Oberg, who was then working at NASA's mission control center in Houston and was one of the best-known independent analysts of the Soviet space program. He called NASA's satellite tracking center to ask whether anything had been launched from the secret Plesetsk cosmodrome. He was told there had been a launch on September 20 at 3:58 a.m. local time, just minutes before the Petrozavodsk sighting.

The rocket, a Vostok-2M, carried the Kosmos-955 military reconnaissance satellite into orbit. The UPI news agency circulated the explanation on September 30. In March 1979, the Finnish astronomy magazine Tähdet ja Avaruus listed the Petrozavodsk event among Plesetsk launches observed from Finland.

Soviet authorities could not say the same thing, because the cosmodrome's existence was a military secret. Plesetsk lies about 200 kilometers south of Arkhangelsk, east of Petrozavodsk. According to Oberg, several Plesetsk launches caused similar mass "UFO scares" between 1977 and 1981. The Soviet press finally acknowledged the cosmodrome's existence only in mid-1983.

The case that started Soviet UFO research

After the event, many residents wrote to the Presidium of the Academy of Sciences, and local authorities and neighboring countries asked whether they had witnessed the effects of military experiments. This was later recounted by Yuli Platov and Boris Sokolov. Platov was deputy chairman of the Academy's expert group, and Sokolov coordinated the investigations of the Ministry of Defense and the Academy. The president of the Academy turned to the government and the military.

As a result, two research projects were added to the state plan in 1978. The Academy of Sciences studied the physical nature of the phenomena, while the Ministry of Defense examined reports from military sources. The program is known as Setka. Over 13 years, it received about 3,000 reports.

According to Platov and Sokolov, nearly all "UFOs" seen at night were the effects of space and ballistic rocket launches, satellite launches, and aircraft and space technology tests. They specifically attributed the Petrozavodsk phenomenon to the launch of Kosmos-955 from Plesetsk.

What came later

Over time, the story grew more colorful:

In April 1978, the American National Enquirer reported that the object's rays had punched holes in windows and paving stones.
Vladimir Azhazha, who later became a well-known Russian ufologist, claimed the object hovered over an anchored ship and was about 104 meters long.
Later accounts added telepathic messages, stalled cars, crashing computers, and the smell of ozone.

According to a summary by the Russian science site Nauka Mail, the broken windows were examined by the Interior Ministry's research institute. The windows had been damaged at different times, and the holes were attributed to metal balls fired from slingshots.

The writer Alexander Kazantsev considered the phenomenon a spaceship, and Felix Zigel, one of the founding figures of Soviet ufology, also regarded it as a genuine UFO. In James Oberg's view, how Russian ufologists handled this case was the real test of their reliability. Since they failed to filter out even an obvious rocket launch, he argued, the legends that followed cannot be treated as reliable data.

The sober take

What is certain? Many people saw the phenomenon in Petrozavodsk at around 4 a.m. on September 20, 1977, and it was also reported around Leningrad and in Helsinki. The Kosmos-955 launch from Plesetsk falls at exactly this time: 3:58 a.m. local time, according to NASA data. Both leaders of the Soviet state UFO research program, Platov and Sokolov, attributed the phenomenon to this launch.

Why did it look like that? At high altitude, where the air is very thin, a rocket's exhaust gases spread out in a wide fan. At dawn, the Sun is still below the horizon, but it already lights up the gas cloud high above, which glows brightly against the dark sky. This is the same phenomenon we covered in our article on rocket spirals. Because the cloud is more than 100 kilometers up and can be hundreds of kilometers wide, it is visible across a huge area, so every observer sees it as if it were hovering directly over their own city. The "enormous" size and the position "over the city" come from a well-known error in judging distance.

Strengths of the case:

many independent witnesses and consistent descriptions;
a contemporary, official news agency report;
a precise time that matches a documented rocket launch.

Weaknesses and open questions:

We found no public, detailed analysis of the exact trajectory and the witnesses' positions.
The movements described at the time (hovering, changes of direction) may come from the apparent motion of a distant glowing cloud, but this can no longer be checked point by point.

What cannot be verified: holes punched in windows and stones, a smaller object falling into the lake, telepathic messages, and technical failures. These appeared in later accounts and are not in the original TASS report.