Posted on by Fraser Cain

Mars Exploration Rover

Mars Rover. Image credit: NASA/JPL

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One of the most successful mission ever sent to Mars is the Mars Exploration Rover program, with the two rovers Spirit and Opportunity. They were launched separately to Mars in 2003 and landed safely several months later. They were supposed to last about 3 months on the surface of Mars, but have now survived more than 5 years.

Spirit and Opportunity used technology developed with the Mars Pathfinder mission. They used an airbag system to land on the surface of Mars without using retrorockets to touch down gently. They also use the rover technology first used with the Sojourner rover, but instead of operating from a base, Spirit and Opportunity were designed to be completely independent, able to communicate directly back to Earth.

The purpose of the Mars Exploration Rover mission (MER) was to search the surface of Mars for evidence of past water on the surface of Mars. Spirit landed in the huge Gusev Crater on Mars, a region that could have been an ancient lake on Mars. Opportunity touched down on the other side of the planet in a region called Meridiani Planum.

Both Spirit and Opportunity are equipped with solar panels that supply electricity to let them crawl around the surface of Mars, as well as their scientific instruments that let them study the surface of Mars and its rocks. They’re also equipped with a grinding tool that lets them scrape away the outer layer of rocks and see the material underneath.

Within just a few months of arriving on Mars, both Spirit and Opportunity fulfilled their mission objectives, and discovered evidence that large quantities of water used to be on the surface of Mars. Spirit discovered hints that water had acted on a rock called Humphrey, while Opportunity found layers of sedimentary rock that would have been formed by deposits in water. Both rovers continued to find additional evidence for the presence of water.

Over the course of their mission on the surface of Mars, both rover traveled several kilometers. Spirit climbed a small mountain, and Opportunity crawled into a large crater to sample the walls for evidence of past water. And both rovers continued to perform quite well, for many years beyond their original estimate life spans.

We have written many articles about the Mars Exploration Rovers for Universe Today. Here’s an article about the troubles for the Spirit rover, and here’s an article about Martian weather.

If you’d like more info on the rovers, you should check out the Mars Exploration Rover homepage from NASA.

We’ve also recorded several episodes of Astronomy Cast about the exploration of Mars. Start here, Episode 92: Missions to Mars, Part 1.

Source: NASA

Posted on by Nancy Atkinson

The Spirit Rover’s Big Discovery

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Amazingly, the two Mars rovers, Spirit and Opportunity, have been working diligently on the surface of the Red Planet for almost four years now. So far, Opportunity has grabbed most of the spotlight, finding evidence for past water on Mars within months after landing on the smooth plains of Meridiani Planum. While Spirit has been working just as hard, if not harder, climbing hills and traversing the rocky terrain of Gusev Crater, she hasn’t yet caused quite the stir that her twin has. But now, a recent discovery by Spirit at an area called Home Plate has researchers puzzling over a possible habitat for past microbial organisms.

What Spirit found is a patch of nearly pure silica, a main ingredient in window glass.

“This concentration of silica is probably the most significant discovery by Spirit for revealing a habitable niche that existed on Mars in the past,” said Steve Squyres, principal investigator for the rovers’ science payload.

The silica could have been produced from either a hot-spring type of environment or another type of environment called a fumarole, where acidic steam rises through cracks in the planet’s surface. On Earth, both of these types of environments teem with microbial life.

“The evidence is pointing most strongly toward fumarolic conditions, like you might see in Hawaii and in Iceland,” said Squyres. “Compared with deposits formed at hot springs, we know less about how well fumarolic deposits can preserve microbial fossils. That’s something needing more study here on Earth.”

Squyres said the patch that Spirit has been studying is more than 90 percent silica, and that there aren’t many ways to explain such a high concentration. One way is to selectively remove silica from the native volcanic rocks and concentrate it in the deposits Spirit found. Hot springs can do that, dissolving silica at high heat and then dropping it out of solution as the water cools. Another way is to selectively remove almost everything else and leave the silica behind. Acidic steam at fumaroles can do that. Scientists are still assessing both possible origins.

One reason Squyres favors the fumarole story is that the silica-rich soil on Mars has an enhanced level of titanium. On Earth, titanium levels are relatively high in some fumarolic deposits.

Meanwhile both rovers are hunkering down for another winter season on Mars. Spirit’s solar panels are currently coated with dust from the huge dust storm the rovers endured this summer, and Spirit will need to conserve energy in order to survive the low light levels during the winter.

“The last Martian winter, we didn’t move Spirit for about seven months,” said John Callas, project manager for the rovers. “This time, the rover is likely to be stationary longer and with significantly lower available energy each Martian day.”

I’m keeping my fingers crossed for another solar panel cleaning windstorm event, which has happened previously, giving the rovers a boost in power.

Original News Source: Jet Propulsion Laboratory News Release