One of the primary components of the ATED is a hollow plastic sphere that is filled with a low-pressure gas combination that mimics human tissue. The spherical detector is the equivalent of one enlarged human cell.
“We rebuilt it as quickly as we possibly could,” Benton said. “We gutted the engineering unit. Oliver Causey worked night and day.”
Graduate student Bryan Hayes works on an Active Tissue Equivalent Dosimeter (ATED) at Oklahoma State University’s Venture 1 labs. An ATED, which measures cosmic radiation, flew on the International Space Station over the summer.
The rebuilt unit, now suitable for space, was put on another truck to NASA. On May 21, 2018, it was launched in the nose of a rocket and was installed in the ISS over the summer. Because of the budget and safety constraints, the unit is relatively primitive, unable to send data down on its own, Benton said. Radiation information is stored on a memory card like the one used in cameras and removed periodically by an astronaut who downloads the information to a laptop to transmit the information back to earth. The day Causey defended his doctoral dissertation, he and Benton returned later to Oklahoma State University’s Venture 1 lab. In Benton’s email inbox was the first set of data ATED collected in space. “(Causey) was thrilled,” Benton said. “He wanted to go home and celebrate. I told him, ‘No. Look at the data and see if it’s working. I have to know.’” Using the data, the pair could follow the space station’s orbit, with spikes in radiation at the poles. As the space station passed over the South Atlantic Anomaly, where the radiation belt dips closest to the earth’s surface, the graph jumped predictably every time. ATED worked, and it worked beautifully. “It was good, clean, solid data,” Benton said. “That was 90 percent of the objective. We can start teasing out more subtle things but the first goal, did it give us the data we expected? Yes. It worked. ‘’ After Causey graduated, graduate student Bryan Hayes took up the cause and is working on a detailed analysis of the data from the ATED’s time in space. Hayes is also taking the lead on another ATED, an improved version, that should make it to the ISS in late 2019 or 2020. It’s a puzzle Benton and his students are trying to complete — placing missing pieces in a sparse map of mankind’s knowledge of the levels and effects of radiation at different altitudes. And the problem isn’t relegated to space. There are questions to be answered in moving up through the atmosphere at all levels et from surface of the earth. Enduci officturio. Onserorrovit autthe iducim doluptati beatquam “This is a stepping stone to the whole program,” he said. dipitatum etus con porrunt.Offic tet iligni arciliq uiatis mollestis “You’re trying to develop an inexpensive detector that’s nihil essusdantis am rendae nus il et omnihil liquas si comnis easy to use andsequi requires power. My hope, ultimately, is to develop quam dolores tem.low Ut abores esed quos sinte apernatiis est a device that we can put on UAVs, drones, balloons — to drop doluptatium, optat. it in there and let it fly and collect as much data as we can and then start teasing out the picture.”
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