Nili Fossae Trough

A "scarecrow" rover at NASA's JPL drives over a sensor while testing a new driving algorithm. Engineers created the algorithm to reduce wheel wear on the Mars Curiosity rover.

Adam Steltzner of JPL holds up a model of a Mars entry capsule.

Examination of a calcium sulfate vein called "Diyogha" by the ChemCam instrument on NASA's Curiosity Mars rover found boron, sodium and chlorine. An image from the rover's Mastcam, at left, provide...

This look back at a dune that NASA's Curiosity Mars rover drove across was taken by the rover's Mast Camera (Mastcam) during the 538th Martian day, or sol, of Curiosity's work on Mars (Feb. 9, 2014).

Curiosity shakes up a scoopful of dirt, dusts off the sampling system and investigates a shiny object on the surface of Mars.

This nearly global mosaic of observations made by the Mars Color Imager on NASA's Mars Reconnaissance Orbiter on Nov. 18, 2012, shows a dust storm in Mars' southern hemisphere.

This illustration depicts a concept for the possible extent of an ancient lake inside Gale Crater.

This mosaic from the Mast Camera on NASA's Curiosity rover shows the view looking toward the "Glenelg" area, where three different terrain types come together.

In the Payload Hazardous Servicing Facility at NASA's Kennedy Space Center in Florida, spacecraft technicians secure an Atlas V rocket payload fairing around NASA's Mars Science Laboratory (MSL).

The four main pieces of hardware that arrived on Mars with NASA's Curiosity rover were spotted by NASA's Mars Reconnaissance Orbiter (MRO).

Clara Ma signs Curiosity

This hole, with a diameter slightly smaller than a U.S. dime, was drilled by NASA's Curiosity Mars rover into a rock target called "Telegraph Peak." The rock is located within the basal layer of Mo...

Engineers put the rover through a human-made earthquake to make sure nothing breaks on its trip to Mars.

This cropped image from NASA's Curiosity rover shows one set of marks on the surface of Mars where blasts from the descent-stage rocket engines blew away some of the surface material.

Thick stacks of clay minerals indicate chemical alteration of thick stacks of rock by interaction with liquid water on ancient Mars.

This full-resolution image from NASA's Curiosity shows the turret of tools at the end of the rover's extended robotic arm on Aug. 20, 2012. The Navigation Camera captured this view.

This version of a self-portrait of NASA's Curiosity Mars rover at a drilling site called "Buckskin" is presented as a stereographic projection, which shows the horizon as a circle. The MAHLI camera...

NASA's Mars Exploration Rover Opportunity used its navigation camera to take the exposures combined into this stereo view of a wee crater, informally named "Skylab," along the rover's route. The co...

This graphic shows how navigators steering NASA's Mars Science Laboratory capsule - with the Curiosity rover tucked inside - are aiming for a pinpoint location above Mars. They liken it to threadin...

This set of artist's concepts shows NASA's Mars Science Laboratory cruise capsule and NASA's Orion spacecraft

NASA has selected Gale crater as the landing site for the Mars Science Laboratory mission.

Results from Opportunity and Curiosity show Mars could have supported life.

These two signature microchips (circled in red) carry 1.2 million names submitted from the public.

Curiosity is a big part of what it means to be human. It's also the name of NASA's next Mars rover. This 60-second video from NASA's Jet Propulsion Laboratory shows how one type of curiosity can in...

Scientist Rob Sullivan explores the Dumont Dunes area, on the hunt for the best place to test-drive the Scarecrow rover.