One of the instruments on a 2016 mission to orbit Mars will provide daily maps of global, pole-to-pole, vertical distributions of the temperature, dust, water vapor and ice clouds in the Martian atmosphere.
Weird Oblong Crater Deepens Mars Mystery
This amoeba-shaped depression on Mars, called Orcus Patera, has had planetary scientists scratching their heads for decades. Despite this sharp new image from the European Space Agency’s Mars Express spacecraft, the crater’s origin is a complete mystery.
Orcus Patera, discovered in 1965 by the Mariner 4 spacecraft, is located near Mars’ equator, between the volcanoes Elysium Mons and Olympus Mons. At 236 miles long, it would stretch from New York to Boston on Earth. Its rim rises over a mile above the surrounding plains, and its floor lies 1,300 to 1,900 feet below its surroundings.
But in spite of lying between two volcanoes and its designation as a patera — the name for deep, complex or irregularly shaped volcanic craters — scientists aren’t at all sure that Orcus Patera has a volcanic origin story. It could be a large impact crater that was originally round but later deformed by compressional forces. Or it could have formed after the erosion of aligned impact craters. The most likely explanation is that it was made in an oblique impact, when a small body struck the surface at a very shallow angle, like a rock skipping on a pond.
The new images show that the crater’s rim is criss-crossed by rift-valley-like structures called graben, which are evidence for active tectonic forces in the area. Smaller graben are also visible inside the depression itself, suggesting that several tectonic events have stretched the ground. The depression also shows “wrinkle edges,” which indicate that the ground has been compressed as well as stretched. The dark shapes near the center of the depression were probably formed when dark material dug up by small impacts in the depression was blown around by the wind.
But these features all appeared after Orcus Patera was formed.
The oblong crater’s origin is still a mystery.
Story: Wired Science
NASA’s Mars rover Opportunity looks back at its tracks in the Martian soil on August 4th, 2010. (NASA/JPL)
Stranded, stubborn Mars rover actually makes a big discovery.
Spirit, the poor Mars Rover that’s been stuck in Martian sand since last year, has actually contributed to a pretty fantastic discovery in its sedentary months: the evidence of subsurface water on Mars.
To recap: Spirit, one of two plucky Mars Rovers that had finished their initial missions in 2004 and had embarked upon, as NASA calls them, “bonus missions” ever since, slipped through Mars’ crust in April 2009 and ended up stuck in the soft sand underneath. Try as it did to back itself out, it remained stuck, and seven months later a second wheel broke down. From then it’s been considered a stationary scientific outpost.
But just as everything in the immediate proximity of your couch becomes slightly more fascinating when your leg is broken, the scientists let the Spirit Rover settle in and conduct some in-depth tests on the soil immediately surrounding it. Those tests found varied composition in the layers of soil underneath the Rover, with generally insoluble materials appearing near the surface and more soluble ones being found deeper down. This is leading scientists to hypothesize that water, perhaps in the form of frost or melted snow, has seeped down into the Martian ground recently and repeatedly.
The Spirit is currently in a low-power hibernation mode as he endures winter, and we’ll have to wait until March, when his solar panels will be in position to collect sun, to see if he wakes up. But in the meantime, good work, little guy—you’re a study in perseverance.
If life ever existed on Mars, then newly discovered mineral deposits on the flanks of a long-dead volcano would be a good place to dig for its remains.
Spotted by a high-powered orbital imager, they’re not the first deposits found on Mars of silica, a mineral used by some simple forms of life, including single-celled algae that evolved early in Earth’s volcanic past.
But the new deposits are the first from a locale with a definite volcanic pedigree, formerly rich in heat and water, as well as minerals — a locale formerly suited, by any earthly definition, for life.
Stand on the slopes of Nili Patera 3.7 billion years ago, and “you would see steam rising up out of the volcano. In the spots we see the deposits, that’s where the highest concentration of steam would be,” said geoscientist Jack Mustard of Brown University. “It’d be like standing on Hawaii, looking across a volcano, seeing the fumaroles where vapors are given off, or standing in Iceland where the hills are steaming.”
Mustard’s findings, co-authored with fellow Brown geoscientist J.R. Skok, were published October 31 in Nature Geoscience. His laboratory is among those that in recent years has processed an extraordinary flow of red planet data, returned by Mars-orbiting spacecraft and surface-exploring robots.
This data has moved researchers beyond looking for signs of water — the latest of which was reported just last week, by both the Spirit and Phoenix rovers — to evaluating potentially once-habitable environments in precise detail.
“It’s the most definitive hydrothermal system we’ve found on Mars. You can see the source of the heat, the driving of the fluids that left the deposits,” said Mustard. “In this deposit, you have the culprit right before you. In other deposits, they’re either sedimentary, or in the center of an impact crater. You have no idea how they happened.”
According to Mustard, traces of any organisms that existed could still be found in the silica, which is non-porous and ideal for preserving fossil remains from the ravages of time and weather. Even after 3.7 billion years, any degradation would come only from silica-penetrating cosmic rays. Those break down biological compounds, but would still leave telltale residues of carbon.
The ExoMars expedition robot, scheduled to launch in 2018, will be equipped with a six-foot-long drill perfect for digging beneath ray-damaged layers.
Mustard isn’t yet prepared to say the rover Curiosity, successor to the Phoenix and Spirit rovers, should visit Nili Patera when it lands on Mars in 2012. Curiosity lacks ExoMars’ planned drilling capacity, and already has a wealth of places to explore: the ancient lake deposits of Holden crater, a stack of sedimentary layers three miles thick in Gale crater, and the Mawrth Vallis river valley.
But Mustard couldn’t help but speculate. “It would be pretty intriguing” if Curiosity found carbon amidst the silica, he said. “Or the rover, as it’s going up the slopes, could dislodge some rocks and look underneath. That’s where the good stuff is.”
Written by: Brandon Keim