Water on Mars is one of the most talked about and controversial subjects in planetary science. It is now well-known that Mars used to be a much wetter place than it is now, although just how much water there was, and how long it lasted, is still a matter of considerable debate. Direct evidence from rovers, landers, and orbiters, including observations of ancient riverbeds, gullies, and lakes, has shown how at one time Mars was much more Earth-like than it is today. Rovers like Curiosity, Opportunity, and Spirit have actually driven over long-dried-up lakebeds, salty playa lakes, and regions of ancient geothermal activity such as hot steam vents. Now, the Opportunity rover is going to visit another feature not yet explored by any other rover or lander: a gully thought to have been carved by water millions or billions of years ago.
NASA’s current rovers, Curiosity and Opportunity, are continuing to explore their respective regions of Mars, with new findings that are providing yet more clues as to the geological history and potential past habitability of this fascinating world. They have also both just completed significant steps in their journeys and are now entering new and exciting phases of their missions. Both missions have found yet more evidence that the Mars we see today – cold and dry – was once much wetter and potentially habitable, at least for microorganisms.
Almost, but not quite… the Opportunity rover is now driving to another area on the hillside where it is currently located, after attempting to reach a difficult rock target. The rover wasn’t quite able to get close enough to the target to conduct further studies, after driving on the steepest slope ever encountered by any rover so far, on Knudsen Ridge.
NASA’s Curiosity rover on Mars may have been stealing the spotlight in recent years, but the other rover, Opportunity, is still going strong after 12 long years. Opportunity has survived the harsh environment and various challenges for much longer than anyone anticipated, and now is taking on a new task: climbing slopes as steep as 30 degrees while searching for deposits of clay minerals which had already been detected by orbiting spacecraft. The region where Opportunity landed, Meridiani Planum, is mostly flat plains, but now on the rugged edge of the huge Endeavour crater, the rover is becoming something of a mountain climber.
We’ve all seen the commercials for the Energizer Bunny, which keeps going and going and going… it just never seems to stop. This makes for an interesting analogy with the Opportunity rover, which is just now passing its 12th anniversary on Mars. Not just 90 days, as hoped for, but 12 years and counting. Incredible. And in that time, Opportunity has helped to fundamentally alter our understanding of this fascinating world.
An interesting image from the Opportunity rover, sol 4023. There are a lot of little shavings-like bits on this brushed rock inside the Spirit of St. Louis crater. Are they just a peculiar result of the brushing of dust by the rover instrument or something else? Are they bits of the rock itself or other embedded material? Similar ones were seen once before, but they seem to be uncommon, even after most brushings.
Two new beautiful composite images, from two different rovers and locations on Mars. The first is a sunset in Gale crater, taken by Curiosity. Martian sunsets look bluish due to the light scattering effects of reddish dust in the atmosphere. The other image, from Opportunity, is of the scenic Lindbergh rock mound in the Spirit of St. Louis crater, on the rim of the huge Endeavour crater. A natural monument!
There has been a lot of discussion the past few days about that lawsuit filed against NASA for supposedly covering up / failing to investigate evidence of life on Mars by the Opportunity rover. This all has to do of course with that “mystery rock” found by Opportunity, nicknamed Pinnacle Island, which somehow just appeared near the rover (most likely dislodged and kicked up by one of the wheels) a few weeks ago.
There is another little Martian mystery that has people talking this week – the odd appearance a few days ago of a small rock a few feet away from the Opportunity rover, it was announced yesterday during the Opportunity: 10 Years on Mars event at NASA.
The rock, nicknamed Pinnacle Island, wasn’t in images taken on sol 3528, but was in images taken of the same spot later on sol 3540. How did it get there and where did it come from?
As principal investigator for the mission, Steve Squyres, explained, the rock is whitish in colour, about the size of a doughnut with a darker spot (“jelly”) in the middle area, which has a concave or hollowed-out appearance. The finding sparked questions and theories ranging from a nugget either left there by a nearby meteor impact or deposited somehow by the rover’s wheels. Squyres thinks the wheel idea is much more likely than the random chance of a meteor happening to hit that close to the rover’s location. Are there any other possibilities?
Microscopic Imager (MI) photos have also been taken of the object and analysis so far of the darker “jelly” has shown it to be rich in sulfur, magnesium and manganese (with twice as much manganese as any other rock examined before by the rover). It is thought that the rock has been flipped over, exposing its underside.
A fascinating mystery that is sure to keep the mission scientists busy for a while.
Thanks also to Jason Major and Stuart Atkinson for use of their complementary images.
This article was first published on Examiner.com.
While Curiosity has been hogging a lot of attention lately, the Opportunity rover is still roving away elsewhere on Mars (since 2004!). Kind of like the Energizer bunny, it just keeps going and going and going…