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Venera-72 stranded in Earth orbit for decades In 1972, the USSR launched its latest pair of probes to explore Venus. The first of two Venera-72 spacecraft within the 3V1 series developed at Lavochkin design bureau successfully departed toward Earth's closest neighbor in the Solar System on March 27. Its sibling followed just four days later, however it was left stranded in Earth's orbit as a result of a booster rocket failure.
Kosmos-482 mission at a glance:
Kosmos-482 mission The Molniya (8K78M) launcher (Manufacturing No. S1500-64) lifted off from Site 31 at a test range near Tyuratam (Baikonur Cosmodrome) on the morning of March 31, 1972, at 07:02:33 Moscow Time (04:02:33 GMT). (537) The launch vehicle carried the 1,184-kilogram V-72 No. 671 spacecraft, (a.k.a. 3V1 or Venera-72 No. 2), which included a main vehicle designed to fly by Venus and a lander intended for a soft-landing on the planet's surface. (202) According to NPO Lavochkin, the spacecraft design and its payloads were identical to those of the Venera-8 probe. Following nominal operations of the first three stages of the launch vehicle, the space probe and its Block-L (2VL) upper stage reached an initial parking orbit with an altitude of 196 by 215-kilometer and an inclination of 51.78 degrees toward the Equator. The subsequent 243-second engine firing of the 2VL stage was designed to send the spacecraft toward Venus, however it lasted only 125 seconds, leaving its payload in a 205 by 9,805-kilometer orbit with an inclination 52.22 degrees. (185) It was taking the spacecraft 201.4 minutes to make a single revolution around the Earth in this orbit. There were also reports that the upper stage fired earlier than planned due to a problem with an onboard timer. Ironically, due to mass constraints for launches to Venus in 1972, the 2VL upper stages used in the V-72 missions lacked the telemetry equipment which was used in previous launches of Venera probes and which could provide a full picture of a potential failure. (1100) As was customary for failed missions that reached orbit during the Soviet period, the official press identified the launch as Kosmos-482 without details about its real destination. Up to five objects associated with the Kosmos-482 launch were reportedly tracked in orbit by Western radars, two of which apparently were quickly losing altitude, reentering atmosphere within few days. Fragments from Kosmos-482 fall to Earth On the night of April 3, 1972, around 1 a.m., multiple observers on the South Island of New Zealand reported seeing flaring objects in the sky. In the next several days, four titanium spheres with a diameter of 380 millimeters and one with a diameter of 250 millimeters were found in various places around the island. After a careful infrared analysis, which revealed markings in Russian language, the debris were linked to the Block-L upper stage of the Kosmos-482 mission. (539) The spherical tanks likely contained pressurized helium gas which was used to pressurize the onboard propellant supply system. However, in response to a formal inquiry, Soviet authorities officially stated that the fragments had not come from the USSR. At the end of June 1972, an additional object apparently separated from the spacecraft: it was officially identified by NORAD as a fragment, but, early on, independent observers suggested that it was the lander jettisoned from the main craft, even though, it could not be confirmed. It was believed that the main spacecraft had reentered on May 5, 1981, (185) while its fragment remained in orbit until 2025. Observable objects associated with Kosmos-482:
Solving mystery of Kosmos-482
A unique image of the second Venera-72 spacecraft (a.k.a. Kosmos-482) taken in 2011 by Ralf Vandebergh appeared to show a joint orbital and descent vehicle, but it was likely an illusion. On Aug. 1, 2011, almost four decades after the launch of Kosmos-482, a prominent satellite observer, Ralf Vandebergh, captured images of the Kosmos-482 spacecraft still orbiting the Earth. It was tempting to see a resemblance to an object in a ground-based image with the fully assembled Venera spacecraft. However, photographs of satellites in space taken from Earth can be very deceiving because they are affected by numerous hard-to-predict factors, such as the slightest camera shake or atmospheric distortion, all capable of producing various visual illusions. New images of Kosmos-482, taken by Vandebergh in April 2025, shortly before the reentry of the spacecraft, again showed an elongated object, but this time, it resembled more a separated Venus descent capsule with a partially deployed parachute or a trailing piece of insulation than a complete spacecraft. And again, the elongated shape could also be the product of very difficult imaging conditions at such a great distance, making a reliable interpretation virtually impossible. Descent Module intentionally separated from falling Soviet Venus probe
For nearly half a century, most assessments of the Kosmos-482 fate were based on Western tracking data, but it was impossible to tell for sure under what circumstances the observable objects had been generated and, in particular, why the lander, intended to separate from the orbital module on approach to Venus seemingly detached from its "mother ship" in orbit around the Earth. The all-but-certain answer came with a contemporaneous document declassified in 2016 but not available to general public until 2022. As it transpired, on April 28, 1972, or nearly a month after the Venera-72 No. 671 probe got stranded in Earth's orbit, the State Commission overseeing the project held a meeting where it reviewed and discussed the status of the two Venera-72 probes — Vehicle No. 670, which was heading to Venus as planned, as well as the situation with Vehicle No. 671, left functioning but stranded in a useless orbit around the Earth under the cover name Kosmos-482. In its official decision, signed by the commission chairman General Mrykin, mission management directed the flight control team of the Chief Operational Control Group, GOGU, and the engineering team at Lavochkin design bureau, among other things, to perform the separation of the Descent Module from the Orbital Module of Vehicle No. 671. The operation could be planned as a test or, possibly, in an effort to reduce the mass of the spacecraft ahead of its inevitable reentry, because, the document instructed the control team to discontinue all operations with Vehicle No. 671 after the separation. The decision noted that the date for the split between the orbital and descent modules was to be coordinated between GOGU, Lavochkin and the State Commission later, thus implying that, as of April 28, 1972, the "mother ship" and the lander were still flying as one spacecraft. Therefore, the document essentially confirmed that the fifth fragment, cataloged by the US military in June 1972 as No. 6073 (International designation 1972-023E) was the 480-kilogram egg-shaped Venus lander separated from the main spacecraft of the stranded Venera-72 probe. Venera-72 No. 671 falls back to Earth After more than 53 years in orbit, the last defunct object from the Venera-72 project likely reentered the Earth's atmosphere in the early hours of May 10, 2025. According to the TsNIIMash institute, the chief research and certification center at Roskosmos, the spacecraft entered the dense atmosphere at 09:24 Moscow Time (06:24 UTC; 2:24 a.m. EDT), 560 kilometers west of the Middle Andaman Island and then fell into the Indian Ocean, west of Jakarta. But according to the US Space Force tracking division, the spacecraft was estimated to reenter earlier over the Pacific — between 05:20 and 05:44 UTC (01:20 – 01:44 EDT). According to ESA, the vehicle was not detected by radar over Germany during the following predicted pass at 07:32 UTC (3:32 a.m. EDT), indicating that the spacecraft had likely reentered.
Known instruments onboard the V-72, No. 671 spacecraft, according to NPO Lavochkin:
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