The climate of Mars has been a topic of scientific curiosity for centuries, in part because it is the only terrestrial planet whose surface can be easily directly observed in detail from the Earth with help from a telescope.
Martian morning clouds (Viking Orbiter 1, 1976)
Mars – most abundant gases – (Curiosity rover, Sample Analysis at Mars device, October 2012)
June 6, 2018
November 25, 2012
The Viking program consisted of a pair of identical American space probes, Viking 1 and Viking 2, which landed on Mars in 1976. The mission effort began in 1968 and was managed by the NASA Langley Research Center. Each spacecraft was composed of two main parts: an orbiter designed to photograph the surface of Mars from orbit, and a lander designed to study the planet from the surface. The orbiters also served as communication relays for the landers once they touched down.
Artist impression of a Viking orbiter releasing a lander descent capsule
Mars image mosaic from the Viking 1 orbiter
Streamlined islands show that large floods occurred on Mars. (Lunae Palus quadrangle)
Scour patterns were produced by flowing water. Dromore crater is at bottom. (Lunae Palus quadrangle)