The four newcomers — representing the U.S., Japan and Russia — will spend the next few days learning the station's ins and outs.

Reaching orbit from NASA’s Kennedy Space Center, the newest crew includes NASA’s Anne McClain and Nichole Ayers, both military pilots; and Japan’s Takuya Onishi and Russia’s Kirill Peskov, both former airline pilots. They will spend the next six months at the space station, considered the normal stint, after springing Wilmore and Williams free.

Radiation from space affects the brain, bones, and genes. These two astronauts will soon begin their recovery A researcher has made a puzzling discovery while analyzing observations taken by NASA's James Webb Space Telescope.