Astronauts and space shuttles constantly are bombarded by radiation. An experiment designed in the Northwest blasted into space today. It’s helping scientists better understand the effects of space radiation on people.
“We can’t really do anything about the fact that we’re being bombarded by these galactic cosmic rays when we’re in space, and we also can’t really shield them very effectively,” said Jeff Katalenich, a nuclear engineer at Pacific Northwest National Laboratory, which is running one of the experiments onboard.
The commercial spaceflight Polaris Program took off from Cape Canaveral in the first of three planned missions. The Dragon spacecraft will orbit for five days. It’ll orbit roughly twice as high as the International Space Station. That’s higher than astronauts have reached since NASA’s Apollo missions in the late 1960s and early 1970s.
Onboard with the crew is an aluminum box, about the size of a small computer speaker. It’s surrounded by metal plates, including tungsten and titanium. During the orbit, those metals will pick up secondhand radiation from high energy cosmic rays and neutrons.
“These metal plates were selected because we knew that when they were exposed to these high energy neutrons, they would activate and create radioisotopes that we would be able to measure after the fact,” he said.
That’s very, very low levels of radiation, Katalenich said.
However, this type of radiation is difficult to predict, he said, even though it’s only one type of radiation astronauts are exposed to.
“That information can be used to help understand and predict the dose levels to astronauts and equipment on the Dragon capsule in the future,” Katalenich said.
Once the capsule plunges into the ocean, the plates will have to be rushed back to PNNL, he said. That’s because some of the secondhand radiation’s half-life is so short. A helicopter will pick up the astronauts and material, and then it will be driven and flown back to Washington state.
At PNNL, scientists will study it in the Shallow Underground Laboratory, which is shielded 40 feet underground from cosmic rays and other background radiation.
This is the second spacecraft this summer to blast off with experiments from PNNL.
Extraterrestrial photosynthesis
Understanding how plants live in space could one day be a key part of space travel. New research out of the Northwest is helping grow plant knowledge on the International Space Station.
Right now, astronauts are growing two types of grasses for scientists on Earth for the Advanced Plant Experiment-09, or APEX-09.
They’re using special red, green and blue LED lights, programmed with light sensitivities that simulate light and dark cycles on Earth.
Later, the grasses will be sent to biologists at PNNL.
They’ll compare the molecules of space-grown grasses to others grown under identical conditions with LED lights at the Kennedy Space Center in Florida.
Pubudu Handakumbura, a biologist at the lab, said she hopes to better understand extraterrestrial photosynthesis in microgravity with extra carbon dioxide.
Learning how plants grow in space will help astronauts on yearslong journeys, like to Mars, she said.
“How do we provide some amount of food for them? And then for their emotional well-being: How do we have that environment that’s away from home but closer to home?” Handakumbura said.
The spacecraft launched Aug. 4, after three years of preparation. Handakumbura said the launch was very exciting. She’s never sent her experiments into space before.
“It took us a long time to really test all of the different steps, building up to that experiment,” she said.
“The level of precision you need and then just meticulous planning,” Handakumbura said, of the different steps. “There’s the science component of it, but then there’s all the other logistics and so many uncontrollable factors.”
The plants will grow in space for 32 days and will return on a later space mission, she said. That’s when Handakumbura and her team will be able to dig deeper into the data.
The experiment is funded by NASA.