Remember when a Soviet spacecraft landed in Wisconsin?

In 1962, Korabl-Sputnik 1 landed smack in the middle of a main street in Wisconsin

Note: This story, published in 2015, is being re-promoted as part of our #sputnik60 celebration of the planet's first artificial satellites, Sputnik 1 and 2. For the month of October 2017, we will be resurfacing cool stories about the Space Race.

Korabl-Sputnik 1, called Sputnik 4 in the West, wasn’t one of the Soviet Union’s greatest triumphs of the early space age. Following a successful mission, a flawed retrofire burn kept the spacecraft aloft until its orbit decayed, sprinkling radioactive metallic debris over Wisconsin.

Korabl-Spunik 1 was the first in a series of missions designed to check out new technologies for the Soviet's manned spaceflight program, namely the Vostok spacecraft and its life support system. To this end, the mission launched with a suite of scientific instruments, a television system, and a humanoid dummy housed in a pressurized cabin.

Diagram of Korabl-Sputnik 1
Diagram of Korabl-Sputnik 1.via spacerockethistory.com

The launch from the Baikonur Cosmodrome in Tyuratam on May 15, 1960 was successful, and the spacecraft ended up in a 174 by 420 mile elliptical orbit. For four days the spacecraft radioed both telemetry and prerecorded voice communications back to Earth exactly as planned. But things changed when it came time for the spacecraft to reenter the atmosphere. The reentry module separated from its service module, but when the retrorockets fired, the spacecraft’s attitude was misaligned. Rather than beginning its fall to Earth, the retro burn boosted the spacecraft into a slightly higher orbit.

At that point, there was nothing left to do but wait until Korabl-Sputnik 1’s orbit decayed. Spadats, the Space Detection and Tracking System at Ent Air Force Base in Colorado (which was fully deactivated by 1980) followed the spacecraft’s progress closely enough to determine it would reenter the Earth’s atmosphere on or around September 6, 1962, somewhere over Wisconsin.

As the date neared, observatories and amateur readied for the event. On August 28, the Smithsonian Astrophysical Observatory asked its Moonwatch teams to keep an eye out for the returning spacecraft. These groups of volunteer astronomers set up watch sites, each hoping to see or even recover the first ever readily accessible debris to return from a prolonged sojourn in space.

On the night of September 4-5, 1962, observers watched the skies for signs of Korabl-Sputnik 1. At 4:49 central time, amateur Gale Highsmith saw the first signs of the spacecraft, a large object burning in the skies overhead that quickly broke into six distinct pieces. He watched as the fires gradually died down.

The brass ring marking where debris landed
The brass ring marking where debris landed.via Wikipedia user Jonathunder

Before long, pieces of the debris were recovered. Bronze pieces scorched the grass on golf courses north of Milwaukee. The burning hot debris yielded molten metal beads that were found on the roof of a church in Manitowoc. And one large piece landed smack in the middle of 8th Street, just offset from the centre white line. This was a massive fragment, a 20-pound steel cylinder welded to a steel plate with one screw. It sat embedded three inches deep in asphalt before two police patrolmen — Marvin Bauch and Ronald Rusboldt — noticed it from their squad car.

Fragments of these recovered pieces were then sent to laboratories to confirm their origin, and it all came down to radiation. American scientists compared debris from Korabl-Sputnik 1 with fragments of the Sikhote-Alin meteorite that landed in Siberia in 1947. The radioactive substances in both bodies was similar enough to convince American scientists the metal had indeed returned from space. Having been bombarded with cosmic rays for years, the metal from the spacecraft emitted radiation at a similar emission rate to the fragment of the meteorite. It was also a similar emission level to what scientists had seen in the American Corona satellites recovered from orbit.

American delegates from the United Nations Committee on the Peaceful Uses of Outer Space attempted to return the large fragment to Russian delegates but the offer was declined. Ultimately, two replicas of the piece that landed on 8th Street were made, and on November 15, 1963, the International Association of Machinists embedded a brass ring in the street to commemorate the spot where the Soviet spacecraft landed in America.