© Reuters

Mount Sharp, 2012 - This image shows the base of the Red Planet's Mount Sharp, officially Aeolis Mons, which rises 5.5 km (3.4 miles) from the valley floor.

© Reuters

Ophir Chasma, 2015 - A view of one of Mars' canyons, located on the northern portion of the planet's vast canyon system.

© Reuters

Nili Patera, 2014 - Located on top of a lava bed at the site of an ancient volcano, Nili Patera is one of the most active dune fields on the planet Mars.

© Reuters

Gullies, 2017 - These viscous, lobate flow features found in the mid-latitudes of Mars resemble terrestrial moraines, suggesting that these deposits are ice-rich, or may have been ice-rich in the past.

© Reuters

Yellowknife Bay, 2013 - The rough spherical features in an area called Yellowknife Bay are interpreted as concretions, implying they were formed by water that oozed through pores in the sediment.

© Reuters

Crater, 2014 - This image of an impact crater on Mars was captured by an orbiter.

© Reuters

Link, 2012 - This rock outcrop, called Link, show rounded gravel fragments, or clasts, that are up to a couple of centimeters in size.

© Reuters

Sand dune, 2014 - These are Mars' northern-most sand dunes and can be seen as they emerge from a winter cover of seasonal carbon dioxide (dry) ice.

© Reuters

Acidalia Planitia, 2015 - This plain serves as the fictional landing site of a crewed mission named Ares 3 in the best-selling novel and film 'The Martian.'

© Reuters

Hellas Planitia, 2011 - The channels on the Hellas Planitia basin range from 1 to 10 m in width.

© Reuters

Noctis Labyrinthus, 2013 - Perched high on the Tharsis rise in the upper reaches of Valles Marineris, this region is notable for its maze-like system of deep, steep-walled valleys.

© Reuters

Gale crater, 2013 - Estimated to be between 3.5 and 3.8 billion years old, this crater is probably also a dry lake near the northwestern part of the Aeolis quadrangle.

© Reuters

Curiosity, 2013 - The car-sized rover designed to explore Gale crater appears as a blue dot near the lower right corner of the image.

© Reuters

Gale crater, 2012 - Pictured is part of Gale crater's wall where a network of valleys believed to have formed by water erosion enters the crater from the outside.

© Reuters

Shaler, 2013 - This rock formation is called Shaler.

© Reuters

Trenches, 2008 - These two trenches were dug by the Robotic Arm of the Phoenix lander.

© Reuters

Victoria crater, 2006 - The impact crater located in the Meridiani Planum plain is roughly 730 m wide and named after one of Ferdinand Magellan's five ships, the first to circumnavigate the globe.

© Reuters

Meteorite, 2005 - The image of this iron meteorite was captured by NASA's Mars Exploration Rover Opportunity.

© Reuters

Columbia Hills, 2004 - This image shows the Columbia Hills, a range of low hills inside Gusev crater.

© Reuters

Water, 2015 - This image shows dark, narrow, 100 meter-long streaks believed to have been formed by flowing water.

© Reuters

Garni crater, 2015 - These dark, narrow streaks emerging out of the walls of Garni crater are called recurring slope lineae.

© Reuters

Circular depression, 2015 - This circular depression on Mars's surface was captured by NASA's Mars Reconnaissance Orbiter in February 2015.

© Reuters

Mars landing, 2012 - This image is one of the first taken after the Curiosity rover successfully landed on Mars on August 6, 2012. 

© Reuters

In color, 2008 - This is one of the first color images of Mars's surface taken after the Phoenix Mars lander spacecraft landed successfully on May 25, 2008. It was the first-ever touchdown near Mars's north pole.

© Reuters

Mars - This is the percussion drill at the end of the Curiosity Robotic Arm, which is making contact with the rock surface on January 27, 2013.

© Reuters

Hellas Planitia, 2008 - This image shows a perspective view of a mountain in eastern Hellas Planitia where large glaciers were detected hidden under rocky debris.

© Reuters

Hellas Planitia, 2008 - This is a different perspective view of the mountain in eastern Hellas Planitia where large glaciers were detected hidden under rocky debris.

© Reuters

Mound, 2017 - This mound appears to have blocked the path of dunes as they move south (to the right of this image).

© Reuters

Cliff, 2017 - This image captured by NASA's Mars Reconnaissance Orbiter shows an interesting rugged cliff edge.

© Reuters

Southern hemisphere, 2017 - Shallow pits can be seen in the bright residual cap of carbon dioxide ice next to a deeper, circular formation that penetrates through the ice and dust, which could be an impact crater or a collapse pit.

© Reuters

Mars, 2016 - The Red Planet is seen here in this NASA Hubble Space Telescope. 

© Reuters

Nili Fossae, 2016 - Located on the northwest rim of Isidis Planitia impact basin, Nili Fossae is one of Mars's most colorful regions.

© Reuters

Mighty sight, 2015 - An aircraft can be seen flying past with the crescent moon and planets Venus and Mars visible nearby.

© Reuters

Outcrop, 2004 - This image taken by the Opportunity rover shows a puzzling rock formation. 

© Reuters

Frost, 2015 - This image captured by NASA's Mars Reconnaissance Orbiter shows frost on Mars's surface.

© Reuters

Rock formation, 2014 - This evenly-layered rock formation displays pattern typical of a lake-floor sedimentary deposit, suggesting a lake once filled this crater.

© Reuters

Cumberland, 2014 - The Curiosity rover drilled into this rock target, nicknamed Cumberland.

© Reuters

Mast Camera, 2012 - This is the Alpha Particle X-Ray Spectrometer seen with the Martian landscape in the background.

© Reuters

Cape Verde, 2006 - Rocky cliffs in the foreground named Cape Verde are located on the rim of Victoria crater. The cliffs were named after the country in honor of Ferdinand Magellan, who visited Cape Verde on his voyage around the world.

© Reuters

Bathurst Inlet, 2012 - This is the top of Bathurst Inlet, a rock on the surface of Aeolis Palus in the Gale crater.

© Reuters

Newton crater, 2011 - These water flows appear in the spring and summer on a slope inside of the Newton crater.

© Reuters

Sheepbed, 2013 - This is an outcrop at the Sheepbed, a mudstone deposit in the Yellowknife Bay area inside Gale crater.

© Reuters

Marquette Island, 2010 - Marquette Island is a rock about the size of a basketball whose texture composition suggest came from deep inside the Martian crust.

© Reuters

Becquerel crater, 2008 - The pattern in this sedimentary bedrock within Becquerel crater suggests rhythmic bedding.

© Reuters

Heimdall, 2008 - The image shows a crater, informally called Heimdall, which has a diameter of 10 km (6 miles). 

© Reuters

Phoenix, 2008 - NASA's Phoenix lander can be seen hanging from its parachute as it descends to the Martian surface.

© Reuters

Echus Chasma, 2008 - A 4,000-meter-high cliff is located in the eastern part of Echus Chasma, one of the largest water source regions on the planet.

© Getty Images

Echus Chasma, 2008 - The network of light-colored, incised valleys look similar to drainage networks found on Earth, suggesting the valleys could have originated from precipitation, groundwater springs, or liquid magma flows.

© Getty Images

Mars Odyssey, 2001 - NASA's 2001 Mars Odyssey spacecraft can be seen orbiting Mars on October 23, 2001.

© Getty Images

Valles Marineris, 2006 - Valles Marineris is Mars's version of the Grand Canyon.

© Getty Images

Reull Vallis, 2004 - The Reull Vallis was likely formed by water. The valley got its name from the Gaelic word for planet.

© Getty Images

Echus Chasma, 2008 - This image shows an aerial view of the Echus Chasma, one of Mars' largest water source regions.

© Getty Images

Echus Chasma, 2008 - Another view of the valleys and cliffs along the Echus Chasma.

© Getty Images

Sleepy Hollow, 2004 - This panoramic view of Mars shows a circular topographic view, dubbed Sleepy Hollow, found in the Gusev Crater.

© Getty Images

Mars Pathfinder, 1997 - This image shows NASA's Mars Pathfinder spacecraft exploring the planet's terrain in 1997.

© Getty Images

Echus Chasma, 2008 - The 2008 images of the Echus Chasma were taken from the European Space Agency's Mars Express.

© Getty Images

Echus Chasma, 2008 - Researchers believe waterfalls may once have plunged over these 4000-meter-high cliffs on to the valley floor. The smoothness of the valley floor suggests it was later flooded by basaltic lava. 

© Getty Images

Phoenix, 2008 - This is an artist's conception of the Phoenix lander landing on the Red Planet. 

© Getty Images

Mars, 1997 - This incredibly sharp portrait of Mars was taken when the planet was about 100 million km (60 million miles) from Earth. 

© Getty Images