In 1975, NASA's Viking 1 spacecraft entered orbit around Mars, carrying a mission to unlock the secrets of the Red Planet. Soon, it released twin landers that drifted toward the Martian surface ...

The most significant change since those 1970's experiments were conducted was the discovery of high levels of perchlorate on Mars. Perchlorate, plus abiotic oxidants, explains the Viking results ...

Tianwen-1's large solar wing dominates the view, but the Martian atmosphere and surface topography are clearly visible. Courtesy of CNSA Read more: China succeeds in putting a probe in Mars orbit ...