Tardigrades could survive interstellar travel in extreme hibernation

Spaceflight caused DNA to leak out of astronauts' cell 'powerhouse." All 14 astronauts studied had increased levels of free-floating mitochondrial DNA in the blood on the day of landing and three days after, ranging from two to 355 times higher than pre-space travel.

How much of the solar system is made of interstellar stuff?

Elevated biomarkers for neurodegeneration found in astronauts returning from space travel