Comic rays could harm passengers and crew during flights, Nasa has warned.
Humans are mostly protected from cosmic rays on planet Earth but travelling at high altitudes is an entirely different matter.
In a chilling statement, Nasa wrote: “Just above you, high-energy particles, called cosmic rays, are zooming in from outer space.
To study the effects of these cosmic rays, the space agency sent a giant helium-filled balloon into the stratosphere to measure cosmic radiation coming from the sun and interstellar space.
It found that because of their time spent in Earth’s upper atmosphere, aircrew are exposed to nearly double the radiation levels of us on the ground.
Exposure to cosmic radiation is also a concern for space travel too.
Learning how to protect humans from radiation exposure is a key step in future space exploration.
Exposure to highly energetic charged particles much like those found in the galactic cosmic rays that will bombard astronauts during extended spaceflights caused significant long-term brain damage in test rodents.