The Phantom Torso Experiment Protected Future Astronauts In The Creepiest Way Possible

For six months in 2001, astronauts aboard the International Space Station had one very creepy roommate. A male dummy with no arms and no legs sat in the ISS's U.S. Destiny Lab to absorb the radiation of space. This was known as the Phantom Torso Experiment, and—as strange as it may seem—it helped protect astronauts for generations to come.

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Space Dangers

When you think about the risks an astronaut takes, you might imagine the launch, the lack of oxygen, and the cold vacuum of space. But there's another invisible danger that's arguably more deadly: radiation exposure. Space is teeming with high-energy particles that wreak havoc on living cells, and can cause everything from cataracts and reproductive damage to cancer and mutations in DNA. On Earth, we're protected from most of these particles by our planet's magnetic field, but in space, there's nowhere to hide.

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Before the galaxy's creepiest astronaut came aboard, scientists had only been able to determine the dose of radiation to which ISS astronauts were exposed with one type of passive sensor, which measures total radiation. The Phantom Torso, on the other hand, was wired with both passive sensors and active sensors, which give real-time readings. Hundreds of sensors were placed at five different locations in the Phantom's body, including his brain, thyroid, heart, stomach, and colon, and still more were placed next to him to measure the radiation inside the spacecraft. There were around 350 sensors in all.

The Phantom Torso on the ISS.

Here's What They Found

For one thing, some models experts had used to estimate radiation dose had been underrepresenting the harms. Many hadn't taken into account free neutrons from galactic cosmic rays, and the experiment found that they contributed a whopping 80 percent of the radiation that astronauts were exposed to. The experiment also showed that there wasn't much of a difference between the amount of radiation that hit the skin and the amount that hit the organs, although the damage was slightly less the further back in the dummy's body it went.

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In the end, the Phantom Torso sharpened our precision in measuring radiation's harms from a wild plus or minus 500 percent accuracy to something closer to 25 percent. Knowing the risks means that the people who design spacesuits and spacecraft can know where and how to focus their protective measures, and that will help astronauts in the future.

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Written by Ashley Hamer February 15, 2017

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