IMAGE 200_299\227.Lbm,The Hubble Space Telescope sent back this picture of Mars, showing in dark blue the region known as Syrtis Major.
IMAGE 200_299\203.Lbm,This Viking photograph was taken as the probe neared Mars. It shows near the centre Mariner Valley; to the left clouds near a volcano, and to the right a frost-filled Argyre Basin.
IMAGE 200_299\231.Lbm,A Viking approach photograph showing at centre the three huge volcanoes on the Tharsis Ridge. To their left is the biggest volcano of all, mighty Olympus Mons.
IMAGE 100_199\138.Lbm,In 1976 a Viking orbiter spots a swirling dust storm (arrowed) travelling across the surface of Mars.
IMAGE 200_299\202.Lbm,This great gash in the surface of Mars, near the equator, is Mariner Valley (Valles Marineris).
IMAGE 200_299\232.Lbm,Clouds gather on the slopes of the biggest volcano in the Solar System, Olympus Mons on Mars, five times the height of Everest and 600 km across at the base. This painting is based on Viking photographs.
IMAGE 0_99\94.Lbm,A false colour picture of Mars's giant volcano Olympus Mons, obtained by computer processing data from the Viking orbiters.
IMAGE 100_199\146.Lbm,A Viking orbiter picture of the Martian surface. It is pockmarked with craters and criss-crossed with channels, some made by lava flows but others maybe by flowing water.
IMAGE 100_199\199.Lbm,This Viking picture of the Martian surface shows what appears to be a watercourse, formed aeons ago by flooding.
IMAGE 200_299\200.Lbm,The Viking 1 orbiter snapped this picture of a "face" etched in the Martian landscape. Some have suggested that intelligent beings carved it.
IMAGE 100_199\184.Lbm,The tiny Martian moon Phobos, from photographs taken by the Viking probes. It is probably a captured asteroid.
IMAGE 200_299\229.Lbm,The smaller of Mars's two moons, Deimos, pictured by Viking.
IMAGE 100_199\143.Lbm,The rust-coloured Martian surface on the plain of Chryse, photographed by the Viking 1 lander in 1976.
IMAGE 200_299\201.Lbm,Part of the Viking 1 lander can be seen in this close-up picture of the Chryse plain of Mars. The tool on the right is the digging arm used to pick up soil samples.
IMAGE 200_299\272.Lbm,The Viking 2 lander's cameras snapped this picture of the Martian surface on the plain of Utopia, showing pockets of frost.
IMAGE 200_299\273.Lbm,A Martian sunset, captured by the Viking 1 lander on the plain of Chryse.
IMAGE 200_299\274.Lbm,Steep cliffs circle the summit crater of Mar's huge volcano, Olympus Mons, which is some 65 km across. This model is based on Viking photos.
IMAGE 500_599\502.Lbm,A Martian roving vehicle trundling across the surface of Mars. Remote-controlled investigation by such vehicles will precede manned exploration next century.
IMAGE 500_599\503.Lbm,A Mars sample and return vehicle touches down on the surface of Mars early next century. It will pick up a soil sample and return with it to Earth, in this study by Jet Propulsion Laboratory.
IMAGE 500_599\504.Lbm,Kicking up the Martian dust, an automatic Mars explorer descends to the surface. Later it will deploy a rover to collect samples from various sites, which it will then return to Earth.
