Growing up in Lake Jackson, April Jean Evans recalls sitting on her grandfather's lap, watching space shuttle missions on TV and going outside to look up at the stars with him. There was never any doubt, she says, that she wanted to work for NASA.

Evans, 32, reached that goal after graduating from Texas A&M University, and her career remained ascendant until she learned of the space agency's plan to irradiate monkeys as part of a $1.75 million experiment. Scientists want to assess health risks astronauts will face from radiation when flying beyond Earth's orbit.

"I began to feel guilty that I was part of an organization doing this," she said.

After finding herself unable to file a formal complaint about NASA's participation in the experiment, and non-productive discussions on the ethics of the research with superiors, Evans resigned in April as leader of a team of engineers working on the International Space Station.

"I had the coolest job in the world," Evans said. "With construction nearly complete, this was going to be the golden decade for the space station. It was such an exciting time for me and it was almost impossible to walk away."

But walk away she did.

Evans said she has never been an animal rights activist. She said she did not even learn about the monkey experiments until January, when People for the Ethical Treatment of Animals protested outside the Houston space center.

Nevertheless, she recently connected with both PETA and Animal Defenders International, which oppose the monkey experiments, and the two organizations encouraged Evans to tell her story.

"NASA can ill afford to lose gifted people like April Evans, who sacrificed her lifelong dream to speak out against animal abuse and backward-looking science," said Kathy Guillermo, PETA's vice president of laboratory investigations.

NASA defends testing

Radiation exposure is one of the greatest hurdles NASA faces in pursuing long-duration spaceflight beyond Earth.

The space agency says the experiments, involving as many as 30 squirrel monkeys, are critical to safeguarding the lives of astronauts during missions to Mars or other long-duration destinations in the solar system.

"On Earth we are protected from most of the space radiation by the Earth's atmosphere and magnetic field," explained Michael Braukus, a NASA spokesman.

"The types of radiation and the doses to be encountered in space are well understood," Braukus said. "However, because cosmic rays are a different type of radiation compared to radiation on Earth, such as X-rays, the potential health risks to astronauts are not well understood."

By understanding how radiation affects the cognitive and motor skills of monkeys, NASA plans to develop biological countermeasures to the risks, Braukus said.

Evans worked at NASA for nine years, spending time supporting efforts to construct the space station and later leading a group that ensures various spacecraft that visit the station, including vehicles from Russia, Europe and Japan, can do so safely and without compromising the station's large array of solar panels.

She believes NASA should be conducting research into preventing radiation from entering space capsules, rather than mitigating it after the radiation has already reached astronauts.

Success with the ESA

Since leaving her position at NASA, Evans has devoted much of her time to building support for an international treaty that would ban primate experiments for the purpose of space exploration.

Already the European Space Agency has adopted such a position, with Director Jean-Jacques Dordain stating in an April 1 letter that ESA's formal position is: "there is absolutely no research interest or planning for experiments with primates."

Such is Evans' aspiration that all space agencies would adopt a similar position. But there's also the real-world issue of no longer having a regular income.

Since leaving NASA, Evans has moved into her brother's spare room. She's also falling into debt.

"I've dedicated myself to trying to stop these experiments," she said. "But at some point I've got to find a way to pay for my car. I know I need to make a living, but it's hard for me to think about that because I never expected to be working anywhere but NASA."

eric.berger@chron.com