It could be lung, liver. It's a heady question to ask - much less try to help answer. It's harder to become an astronewt than an astronaut. But the stakes are astronomically higher. He and his colleagues will focus on a couple of theories.
Astronauts have some changes in their bones when they're up in space.
Their spines snap back to normal once back on Earth. Pfeiffer will examine the space newts to see if the spaces between their vertebrae widened. If they did, maybe clues will emerge about why that happens to humans. The scientist also will aim his electron microscope toward more basic cell structures. The electron microscope is a very large instrument, a kind of a microscope that allows you to look at the interior of cells.