The Phantom Torso - Space Radiation

Supernova explosions like this one accelerate atomic nuclei to nearly light speed. The resulting "cosmic rays" pose a potential hazard to astronauts. [More information]

"With the active detectors, we can correlate the time the radiation was received with the position of the spacecraft," explains Badhwar. "We can separate out quite reliably when we were in the Anomaly and when we were in the Galactic Cosmic Ray region.” This kind of split makes radiation models derived from such data applicable to interplanetary missions, too. To assess astronaut exposure on a trip to Mars, for example, "we'll just switch off the Van Allen Belt particles,” says Badhwar.

Radiation models devised by Badhwar and colleagues will be able to estimate how much radiation reaches an astronaut's internal organs simply by looking at the dose on his or her skin. That's important, because while the permissible radiation limits are based on internal exposures, practically speaking, all that can be measured is what occurs on the skin.

Such models are also scalable. Rather than giving a blanket risk assessment for all crew members, they can be customised to each individual in terms of height, weight, and even personal histories: how the astronaut flies an aircraft, or what medical tests he or she might have taken. All this contributes, says Badhwar, to total radiation exposure.

Even our internal bacteria rate a careful look: If a crew member gets too much radiation, it could kill the digestive bacteria essential for breaking down food.

The "South Atlantic Anomaly" is an area of trapped radiation located over the east coast of Brazil. [More information]

Space station crew members will be sending data from the Phantom's five active dosimeters back to Earth about every ten days. When the device returns to Earth next fall, Badhwar and his team will be able to examine results from Fred's passive detectors as well.

"The thing that we're really going after is to get as good a handle as we can on what the organ exposures really are.” he says. The goal is to make sure that the crew is exposed to the least amount of radiation possible.