gerontology

Spaceflight produces aging-like changes in bone, muscle and the cardiovascular system, most of which largely reverse after return. Here is what the NASA Twins Study and ISS research do, and do not, show about aging.

Some scientists genuinely believe today's children could live for centuries. Here's what aging actually is, what we'd need to defeat it, and what a 1,000-year lifespan would mean for humanity.