NASA halts monkey radiation experiment for now

This week I read an article on NASA's halt on radiation experimenting on squirrel monkeys.
The main points of the article are:

• irradiate squirrel monkeys to better understand the risks of long-duration spaceflight on humans
• called for exposing 27 squirrel monkeys to high-energy gamma-ray radiation so researchers could observe its effects on the monkeys health and task performance
• Animal-rights activists called the project cruel and poorly designed
• NASA has said that studies involving other primates are essential to predicting the neurobehavioral effects of space radiation on humans
• The radiation study would reportedly expose the monkeys to radiation similar to what astronauts would experience on a three-year voyage.

NASA has, for now, stopeed its experiment on squirrel monkeys. They wanted to do this experiment to see the effects that radiation would have on their behavior and health, because astronauts traveling on a three-year voyage would be exposed to similar radiation. Many people feel that this is cruel treatment of animals, and are not at all okay with NASA's research techniques.