The Petrozavodsk phenomenon

The full file

At about four in the morning, Moscow time, on 20 September 1977, people awake in Petrozavodsk, the capital of Soviet Karelia, saw a bright light rise in the north-eastern sky. Among them were ambulance crews, police on duty, workers at the cargo port, a geologist and a former pilot. Over roughly ten to fifteen minutes the light grew a translucent shell, threw out curved streams of light and seemed to hang over the city before moving away towards Lake Onega. Within the same hour similar displays were seen in Leningrad and its suburbs, across Karelia, in Estonia and over Helsinki, where the flight controller at Vantaa airport described a pulsing fan of light.

The report that reached the press

Nikolai Milov, the TASS correspondent for Karelia, filed the story. It went out on 22 September and appeared the next day in Izvestiya, Pravda, Sotsialisticheskaya Industriya and other papers. In translation, it described a huge "star" that spread over the city "in the form of a jellyfish", showering it with fine streams of light that gave the impression of pouring rain, and said the event lasted ten to twelve minutes. The director of the Karelian hydrometeorological observatory, Yu. A. Gromov, was quoted as saying no technical experiments were being carried out in Karelia or on the Kola Peninsula. Vladimir Krat, director of the Pulkovo observatory, said his astronomers had seen a fiery ball cross the sky from south to north. Milov later wrote that the item's circulation was cut short after its release; that account rests on his memoir alone.

What evidence exists

No photograph is known. The core record is a restricted Academy of Sciences report dated 20 October 1977, The Phenomenon of 20 September 1977: description and preliminary analysis, by L. M. Gindilis, D. A. Menkov and I. G. Petrovskaya. It lists its inputs: written witness statements from Petrozavodsk certified by the observatory, a train crew at Podporozhye, a meteorologist at Sortavala, the shift supervisor of port supervision at the Leningrad sea port, the night shift at Pulkovo airport, the crew of the fishing vessel Primorsk, letters from the Baltic and Finnish press reports. It divides the event into phases. Around 03:00 the Leningrad port staff watched a dazzling cylindrical body sink towards the horizon for 25 minutes; at 03:30 the Primorsk crew saw a silent light turn sharply north. The main phase began between 04:00 and 04:05 and was seen almost simultaneously across the region. The report also records holes found in window glass in four Petrozavodsk houses, while stating that any link to the event needed separate discussion. Radar data, it says, were contradictory: a UPI report claimed Helsinki airport radar tracked the object, while the night-shift chief at Leningrad's Pulkovo airport said the object seen there gave no radar return. The document survives as a published text on Astronet, the Moscow State University astronomy portal; its original archive location is not given.

What investigators concluded

The authors could not reach a satisfactory understanding of the event. They judged its scale too large for technical experiments in satellite orbits, could not fit a single high object to all the sightings, and noted an active magnetic storm and aurora that night. According to Boris Sokolov and Yuli Platov, who later ran the state programme, the Academy president Anatoly Aleksandrov asked the Military-Industrial Commission to investigate, and northern European governments wrote to him asking whether Soviet weapons tests were responsible. From 1978 the commission funded two research themes, Setka MO for the defence ministry and Setka AN for the Academy, which collected some 3,000 reports over thirteen years. Writing in 2000, Sokolov and Platov said the Petrozavodsk sighting "was eventually attributed to the launch of the Kosmos 955 satellite" from Plesetsk.

The leading explanation: Kosmos-955

The American space analyst James Oberg argued in 1982 that the display was a pre-dawn launch from Plesetsk, a site the Soviet Union did not then acknowledge. Launch records support the timing. Jonathan McDowell's catalogue gives Kosmos-955, a Tselina-D electronic intelligence satellite, as launched on a Vostok-2M rocket from Plesetsk at 01:00:59 UTC, which is 04:00:59 Moscow time, into an orbit inclined at about 81 degrees. A northbound rocket climbing into sunlight above a dark sky would explain the simultaneity of the main phase across hundreds of kilometres, the expanding shell of exhaust, and the report's own finding that the object departed northwards at most sites. Later Setka cases, such as 14 June 1980, were matched to Plesetsk launches in the same way. One retelling, in The Moscow Times, puts the launch at 3:58 a.m.; the catalogue time is three minutes later.

The weaknesses are real. The launch cannot account for the Leningrad port and Primorsk sightings an hour earlier, witnesses who placed the light below the cloud, the holes in the glass, or the separate reports of the following weeks, including a weather-radar return over Petrozavodsk on 20 October.

What remains unexplained

The main phase is now widely, though not universally, treated as Kosmos-955. Disputed are the earlier and later sightings, which may be unrelated aurora, meteors or other launches; the Helsinki radar claim, never documented; and the reach of the event itself. Later accounts extend it from Copenhagen to Vladivostok and count dozens of objects, but the Academy's own list runs from Pskov and Estonia to the White Sea, with one report from the Black Sea coast.

Sources

• L. M. Gindilis, D. A. Menkov, I. G. Petrovskaya, "The phenomenon of 20 September 1977: description and preliminary analysis" (archived) — USSR Academy of Sciences, 1977, published on Astronet. Witness list, phases and times, window holes, radar, conclusions.
• Nikolai Milov, personal archive memoir (archived) — Sever (Petrozavodsk), 2010. Full TASS text of 22 September 1977, the Gromov and Krat comments, Helsinki press reports.
• Boris Sokolov and Yuli Platov, "A History of State UFO Research in the USSR" (archived) — Skeptical Briefs, 2000. Aleksandrov, the northern European letters, Setka MO and Setka AN, the Kosmos-955 attribution.
• General Catalog of Artificial Space Objects, launch list (archived) — Jonathan McDowell, current. Kosmos-955 launch time, rocket and site.
• Tselina-D (11F619, Ikar) (archived) — Gunter's Space Page. Second check on the Kosmos-955 date, site and rocket, and the satellite's purpose.
• James Oberg, "The Great Soviet UFO Cover-up" (archived) — MUFON UFO Journal, 1982. The Plesetsk launch explanation and later launch-related sightings.
• Matthew Bodner, "Little Green Men: A Look at the Official Soviet X-Files Investigation" (archived) — The Moscow Times, 2016. Platov's role, the 3:58 a.m. launch time given via Oberg, Setka totals.