In 2006, ISS astronauts threw an old Russian spacesuit stuffed with clothes into orbit; SuitSat circled Earth twice before its radio signal became unexpectedly weak

On February 3, 2006, astronauts aboard the International Space Station did something that sounds like it came straight out of a science fiction movie. In a routine spacewalk, commander Bill McArthur and flight engineer Valery Tokarev released an old and empty spacesuit into space. NASA's own account says the suit was an old Russian Orlan model that the crew no longer needed, stuffed mostly with old clothes to give it a human shape before being sent into orbit on its own.

Tokarev reportedly said, "Do svidaniya... Goodbye, Mr. Smith," as he released the suit, according to a contemporaneous NBC News report, and the nickname stuck with the whole team. Anyone watching the live feed that day would have seen an eerie sight: a human-shaped suit drifting away from the station. But the whimsical name masked a serious technical goal, not just a bizarre photo opportunity.

What the floating spacesuit was built to do

The helmet held a tiny radio transmitter and battery pack, turning the suit into a makeshift satellite called SuitSat-1. There is another name for the same program in Russia. According to the phys.org article about the launch, the project is also known as RadioSkaf or Radio Sputnik and was sponsored by Amateur Radio on the International Space Station, an international team of ham radio enthusiasts collaborating with the astronauts on their communication experiments.

As Space reported, the engineers expected the suit to transmit messages in five languages, along with an image and telemetry data, for about 10 days before it stopped working. It is worth noting that the transmission used the VHF band, the specific 145.990 MHz frequency commonly monitored by amateur or "ham" radio enthusiasts, though VHF frequencies more broadly are also used for aviation, maritime, and other commercial communications. The idea was that anyone with the right equipment would try to intercept the voice of the suit as it passed overhead.

Two orbits, then a puzzling silence

Ground controllers reported that the suit's signal weakened unexpectedly. NASA commentator Rob Navias mentioned that the suit failed to transmit data after the second orbit of the Earth, which translates to about three hours of flight, as per the Space.com story about the project. At that point, the whole project looked like a doomed venture in just a few hours of operation. But that is not the end of the story. The Space.com report explains that NASA spokesman James Hartsfield revealed that the battery life of the suit turned out to be longer than anticipated. The transmitter had not failed completely; it had only weakened to the point that most receivers could not get a clear signal, likely because freezing temperatures in space affected the suit's electronics.

A whisper that wouldn't quite go away

Ham radio fans kept tuning in and hearing faint traces of the signal weeks after the “failure” was announced. Sergei Samburov, the project’s deputy director, told the Russian news agency Interfax-AVN, in comments carried by the phys.org report on the mission, that the SuitSat-1 transmitted approximately 3,500 messages to Earth over approximately two weeks, with the last confirmed transmission on February 18, 2006. It was a quiet win for the small team behind it, considering the first reports of a dead satellite.

A creative, low-cost experiment in space

SuitSat-1 did not pose any threat to the space station or its equipment. Instead, it transformed a potentially discarded device into a working experiment. The SuitSat-1 mission also showed how a low-budget and innovative project can nevertheless attract the interest of students and ham radio enthusiasts around the world, despite the absence of any major funding or specifications for the project. For many children listening to a regular radio set at home, it was their first chance to feel close to something flying in space.

The suit itself did not survive much longer than its famous weak signal. The phys.org report on the mission notes that SuitSat-1 was expected to continue to orbit in a naturally deteriorating orbit until it reentered the Earth's atmosphere and burned up completely, which happened on September 7, 2006, about seven months after its release. Even cast-off space hardware can serve one more purpose before it is gone, and SuitSat-1 remains a symbol of that 20 years later.