Astronauts’ hearts just passed a surprising test for Mars

Astronauts’ hearts just passed a surprising test for Mars

A new study tracking 13 astronauts suggests that the human heart may be surprisingly well equipped for a journey to Mars, especially with regular exercise during spaceflight. Researchers found that astronauts' hearts adapted to months of weightlessness and handled simulated Martian gravity without major problems, offering new hope for future missions to the Red Planet.