Humphrey on the Inside

This section from a panorama that NASA's Mars Exploration Rover Spirit acquired in October 2005 from the top of "Husband Hill" presents the view toward the south from that summit.

NASA's twin robot geologists, the Mars Exploration Rovers, will launch toward Mars in 2003 in search of answers about the history of water on Mars. The rovers will be targeted to sites that appear ...

"Marathon Valley" on Mars opens to a view across Endeavour Crater in this scene from the Pancam of NASA's Mars rover Opportunity. The scene merges many exposures taken during April and May 2016. Th...

NASA's Mars Exploration Rover Opportunity used its navigation camera (Navcam) to record this image of the northern end of "Solander Point," a raised section of the western rim of Endeavour Crater.

This view combines frames taken by the panoramic camera on Opportunity's 652nd through 663rd Martian days, or sols (Nov. 23 to Dec. 5, 2005), at the edge of "Erebus Crater."

Wheel tracks from NASA's Mars rover Opportunity descending and departing the "Cape Tribulation" segment of Endeavour Crater's rim are visible in this April 21, 2017, view from the rover's Panoramic...

In late November 2005 while descending "Husband Hill," Spirit took the most detailed panorama so far of the "Inner Basin," one of the rover's target destination.

See how the scientists and engineers on Earth stretch their imaginations to design the best rover system to deal with the unpredictable dangerous terrain on Mars. Rover team members at Jet Propulsi...

Gazing across the landscape of the "Columbia Hills" in Gusev Crater on Mars, scientists saw hints of tilted rock layers across the area traversed by the Spirit rover.

Take JPL Education's Pi Day challenge featuring real-world questions about NASA spacecraft -- then tweet your answers to @NASAJPL_Edu using the hashtag #PiDay. Answers will be revealed on March 16.

Transverse Impulse Rocket System (TIRS) Configuration

Landing a spacecraft on Mars is one of the trickiest things we do. This 60-second video explains how it's done, and the three landing systems we use at the Red Planet.

With a model of NASA's Opportunity rover behind him, John Callas, project manager of the Spirit and Opportunity Mars rovers, speaks about the rovers' achievements at the agency's Jet Propulsion Lab...

This Martian scene shows contrasting textures and colors of "Hinners Point," at the northern edge of "Marathon Valley," and swirling reddish zones on the valley floor to the left.

This is the 3-D anaglyph showing a microscopic image taken of soil featuring round, blueberry-shaped rock formations on the crater floor at Meridiani Planum, Mars. This image was taken on the 13th ...

In the Payload Hazardous Servicing Facility, workers prepare to lift the Mars Exploration Rover-1 (MER-B) onto a spin table during preflight processing of the spacecraft.

From left: Dave Lavery, program executive for Solar System Exploration at NASA Headquarters, Dr. Ed Weiler, associate administrator, Office of Space Science, NASA Headquarters, Pete Theisinger, (fo...

Composition measurements by NASA's Mars Exploration Rover Opportunity confirm that this rock on the Martian surface is an iron-nickel meteorite.

The piece of metal with the American flag on it in this image of a NASA rover on Mars is made of aluminum recovered from the site of the World Trade Center towers in the weeks after their destruction.

NASA's Mars Exploration Rover Opportunity obtained this view from the top of the "Cape Tribulation" segment of the rim of Endeavour Crater. The rover reached this point three weeks before the 11th ...

The High Resolution Imaging Science Experiment (HiRISE) camera on NASA's Mars Reconnaissance Orbiter acquired this image of the Opportunity rover on the southwest rim of "Santa Maria" crater on New...

NASA's twin robot geologists, the Mars Exploration Rovers, will launch toward Mars in 2003 in search of answers about the history of water on Mars.

Late-afternoon shadows include one cast by the rover itself in this look toward the floor of Endeavour Crater by NASA's Mars Exploration Rover Opportunity. The rover's Navcam recorded the three com...

The first episode documents the hurdles leading up to both launches. From Mother Nature being uncooperative to a problem with the cork insulation on the rocket, lift-off was no small feat. Ultimate...

Opportunity captured this vista of "Victoria Crater" from the viewpoint of "Cape Verde," one of the promontories that are part of the scalloped rim of the crater.