NASA officials say the best chance to hear from the napping Spirit rover again will be in September or October, but the timing of the robot's revival from winter hibernation is an engineering guessing game. Spirit was forced to sleep by the cold winter in the Martian southern hemisphere, where low sun angles were not sufficient to power the rover through solar panels. The stranded rover last communicated with Earth on March 22. Spirit has been stuck in a sand pit known as Troy since April 2009, leaving the rover tilted away from the sun and limiting its ability to produce electricity. The winter solstice at Spirit's location was May 13, and conditions should now be improving. But the rover's batteries likely won't be collecting enough sunlight to begin communicating again until September or October.

Mars rover team members have begun informally naming features around the rim of Endeavour Crater, as they develop plans to investigate that destination when NASA's Opportunity rover arrives there after many more months of driving. A new, super-resolution view of a portion of Endeavour's rim reveals details that were not discernible in earlier images from the rover. Several high points along the rim can be correlated with points discernible from orbit. Super-resolution is an imaging technique combining information from multiple pictures of the same target to generate an image with a higher resolution than any of the individual images.

California middle school students using the camera on NASA's Mars Odyssey orbiter have found lava tubes with one pit that appears to be a skylight to a cave. The students in science teacher Dennis Mitchell's class at Evergreen Middle School in Cottonwood, Calif., were examining Martian lava tubes as their project in the Mars Student Imaging Program offered by NASA and Arizona State University. Students in this program develop a geological question, then target a Mars-orbiting camera to take an image that helps answer the question. Mars Odyssey has been orbiting the Red Planet since 2001, returning data and images of the Martian surface and providing relay communications service for the twin Mars rovers, Spirit and Opportunity.

Rocks examined by NASA's Spirit Mars Rover hold evidence of a wet, non-acidic ancient environment that may have been favorable for life. Confirming this mineral clue took four years of analysis by several scientists. An outcrop that Spirit examined in late 2005 revealed high concentrations of carbonate, which originates in wet, near-neutral conditions, but dissolves in acid. The ancient water indicated by this find was not acidic. NASA's rovers have found other evidence of formerly wet Martian environments. However the data for those environments indicate conditions that may have been acidic. In other cases, the conditions were definitely acidic, and therefore less favorable as habitats for life. Laboratory tests helped confirm the carbonate identification. The findings were published online Thursday, June 3 by the journal Science.

The life of a Mars rover is probably bit like that of Wall-E at the start of the Pixar movie: a lot of lonely treks in dutiful fulfillment of a mission through the remains of a planet's earlier days. The rovers Spirit and Opportunity may not be Hollywood icons, but they have done NASA proud. And in just the last day or so, Opportunity hit yet another milestone--it now holds the record for the longest active service on the surface of Mars, surpassing the mark of six years, 116 days (in Earth time) set by the Viking 1 lander, which arrived on the Red Planet in the summer of 1976.

NASA's long-lived twin Mars rovers Spirit and Opportunity have set a new endurance record on Mars, with Opportunity hot on the heels of its sister robot for the title of longest-running mission on the Martian surface. Opportunity today matched the Mars mission lifespan of NASA's iconic Viking 1 lander, which spent six years and 116 days (for a total of 2,245 days) working on the red planet in the mid 1970s and early 80s. If Opportunity survives three weeks longer than its older robotic twin Spirit, which has been silent for weeks but may actually be hibernating, the rover will take the all-time record for the longest mission on Mars. The two solar-powered rovers recently experienced their fourth Martian winter solstice – the day with the least amount of sunlight at their respective spots on Mars – on May 12.

There is a new champion on the red planet, in terms of longevity that is, the Mars Exploration Rover Opportunity has surpassed the endurance record of Viking 1. The lander held the record for decades, (the lander was accidentally turned off in 1982 and contact could not be reestablished) until this week when Opportunity surpassed it. The Mars Exploration Rovers Spirit and Opportunity have been on Mars since 2004 and have provided countless new discoveries about our next door, (celestially speaking) neighbor. The rovers were only expected to last 90 days – and have gone on to last some six years, (Spirit has not communicated with ground controllers and is thought to be in hibernation mode). Spirit may yet wake up and yank the duration-prize from her sister – but until then the prize goes to Opportunity. Much of the twin rovers’ missions successes have gone to this particular rover.

This is the first image ever taken of Earth from the surface of a planet beyond the Moon. It was taken by the Mars Exploration Rover Spirit one hour before sunrise on the 63rd Martian day, or sol, of its mission. (March 8, 2004) The image is a mosaic of images taken by the rover's navigation camera showing a broad view of the sky, and an image taken by the rover's panoramic camera of Earth. The contrast in the panoramic camera image was increased two times to make Earth easier to see.The inset shows a combination of four panoramic camera images zoomed in on Earth. The arrow points to Earth. Earth was too faint to be detected in images taken with the panoramic camera's color filters.

A historic milestone could be made on Mars this week. On Thursday, NASA's beleaguered Spirit rover could become the longest-running mission on the surface of Mars, surpassing the Viking 1 lander's record of six years and 116 days of operation on the Martian surface — if it's still alive, that is. Spirit fell silent on Mars on March 31, when it skipped a planned communications session with Earth. It may be hibernating through the harsh Martian winter. But even if Spirit doesn't survive, its robotic twin Opportunity is poised to break the Mars mission record in early May. Beating Viking's record, which NASA set in the 1980s, would be a major feat for a rover the size of a golf cart that was only supposed to last for three months and spent the past year stuck in Martian sand. The milestone would also be a welcome surprise to the team of scientists and engineers that have been commanding Spirit for these past six years.

With new software that allows Opportunity to photograph rocks and other aspects of the Martian terrain and decide for itself what is worth closer inspection, the rover took an up-close look at a few rocks ejected by the impact that created Concepción. What Opportunity has seen are chunks of the same type of bedrock it has seen at hundreds of locations since landing in January 2004: soft, sulfate-rich sandstone holding harder peppercorn-size dark spheres like berries in a muffin. The little spheres, rich in iron, gained the nickname "blueberries." But these rocks have some unusual twists as well. "It was clear from the images that Opportunity took on the approach to Concepción that there was strange stuff on lots of the rocks near the crater," said Steve Squyres of Cornell University in Ithaca, N.Y., principal investigator for Opportunity and its twin rover, Spirit. "There's dark, grayish material coating faces of the rocks and filling fractures in them. At least part of it is composed of blueberries jammed together as close as you could pack them. We've never seen anything like this before."

NASA says the team that operates its Mars rovers Spirit and Opportunity will receive the 2010 International Space Ops Award for Outstanding Achievement. The space agency said the citation for the award, to be presented April 29 in Huntsville, Ala., says: "For remarkable success in meeting unique and varied challenges of operating a rover on Mars and establishing a model for future in-situ operations." The award is presented every two years, with the recipient selected from members of several nations' space agencies.

NASA's Mars rover Opportunity is getting a chance to call its own science shots on the red planet. New software uploaded to the intrepid robot now allows Opportunity to make its own decisions about whether or not to make additional observations of Mars rocks it spots when it arrives at a new location. The rover has already taken its first automated images of Martian rocks to test out how well the new program works. "It's a way to get some bonus science," said rover driver Tara Estlin of NASA's Jet Propulsion Laboratory in Pasadena, Calif., also a member of JPL's Artificial Intelligence Group, which developed the new software.

This image shows the Mars Exploration Rover Opportunity perched on the edge of Concepción Crater in Meridiani Planum, Mars. This image was taken by HiRISE on February 13, 2010, on sol 2153 of Opportunity’s mission on Mars. If you look closely, you can see rover tracks in the ripples to the north and northwest of the rover! Wow! See below for a wonderful colorized close-up version by Stu Atkinson that shows the tracks very clearly. Scientists use these high-resolution images (about 25 cm/pixel) to help navigate the rover. In addition, rover exploration of areas covered by such high-resolution images provides “ground truth” for the orbital data. Oppy has moved along from Concepcion and is now heading towards a set of twin craters. You can check out Stu's blog Road to Endeavour to see what Opportunity is seeing these days. One milestone (meterstone?) Oppy recently reached was hitting 20 km on her odometer and she seems to continue to be in great operating condition. Go Opportunity!

NASA's Spirit rover should be able to wriggle free of its sandy trap on Mars after all, says a scientist for the mission. But the plucky robotic explorer will need to survive the bitter Martian winter first. In April 2009, Spirit's wheels broke through a thin surface crust and got mired in the loose sand below. After months of trying unsuccessfully to free the rover, NASA declared on 26 January that Spirit would henceforth be a stationary lander mission rather than a rover. But the announcement was "a little bit premature", rover scientist Ray Arvidson of Washington University in St Louis, Missouri, told researchers at the Lunar and Planetary Science Conference in Houston, Texas, on Monday. In nine drives between 15 January and 8 February, mission members coaxed the rover into driving backwards by 34 centimetres – "pretty good for a lander", Arvidson said. That far surpasses the mere millimetres of motion Spirit had managed in previous efforts.

Although it might seem like a headline from The Onion, the story's actually true. NASA's being forced to cut four million dollars from the Mars rover project. In order to meet that requirement, they'll have to put one rover, Spirit, to sleep — a "hibernation" period. The team at NASA's Jet Propulsion Lab (JPL) will also have to put the other rover, Opportunity, on a diminished work cycle. But in actuality, they won't be cutting what Opportunity's doing — they'll just be spreading it out over a longer period of time.