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Neighbouring volcanoes on Mars

Copyright ESA

ESA’s Mars Express has returned images of mist-capped volcanoes located in the northern hemisphere of the red planet. Long after volcanic activity ceased, the area was transformed by meteor impacts that deposited ejected material over the lower flanks of the volcanoes.

Permanent and transient features are on display in this newly released image of Mars. The image is derived from data acquired during three orbits of ESA’s Mars Express between 25 November 2004 and 22 June 2006. In that time, these dead volcanoes were not expected to change but, during the middle orbit, Mars Express captured icy clouds drifting past the summit of Ceraunius Tholus.

By the time Mars Express crossed again and took the final strip of data needed for this image, the clouds had long since dispersed and so there is a sharp line across them in the finished mosaic.

The Latin word “tholus” means a conical dome and the base of Ceraunius Tholus is 130 km across, while the peak rises 5.5 km above the surrounding plains. At its summit is a large caldera 25 km across. With similar morphology to its neighbour and lying 60 km to the north, Uranius Tholus is [...]

Mars Express close flybys of martian moon Phobos

Copyright ESA

Mars Express has returned images from the Phobos flyby of 9 January 2011. Mars Express passed Mars’ largest moon at a distance of 100km.

Light and dark in the Phoenix Lake

Copyright ESA

They say you can’t judge a book by its cover but, with planets, first impressions do count. New images show where complex fault lines in Mars’ Phoenicis Lacus region have resulted in terrain with a distinctly contrasting appearance.

Nineteenth-century astronomers were the first to see Phoenicis Lacus on Mars. They identified it as a dark spot, and thought that it resembled a sea. Now we know that it is not a body of water but the southwestern extension of the complex Noctis Labyrinthus system, which stretches away from the giant volcanoes of Mars’s Tharsis region.

The brightness of a surface feature is still the first thing planetary astronomers notice. It is known as the albedo and is partly determined by the composition of the surface material. For example, ice is more reflective than rock. The texture of the surface also plays a part, with rough surfaces reflecting less sunlight and so appearing darker than smooth surfaces.

Phoenicis Lacus has an area of 8100 sq km (59.5 x 136 km), which corresponds to the size of Corsica. Only a small portion of it appears in this image, which was obtained on 31 July 2010 using the [...]

Study Links Fresh Mars Gullies to Carbon Dioxide

Copyright NASA

A growing bounty of images from NASA’s Mars Reconnaissance Orbiter reveals that the timing of new activity in one type of the enigmatic gullies on Mars implicates carbon-dioxide frost, rather than water, as the agent causing fresh flows of sand.

Researchers have tracked changes in gullies on faces of sand dunes in seven locations on southern Mars. The periods when changes occurred, as determined by comparisons of before-and-after images, overlapped in all cases with the known winter build-up of carbon-dioxide frost on the dunes. Before-and-after pairs that covered periods only in spring, summer and autumn showed no new activity in those seasons.

“Gullies that look like this on Earth are caused by flowing water, but Mars is a different planet with its own mysteries,” said Serina Diniega, lead author of a report on these findings in the November issue of the journal Geology. She analyzed these gullies while a graduate student at the University of Arizona, Tucson, and recently joined NASA’s Jet Propulsion Laboratory, Pasadena. “The timing we see points to carbon dioxide, and if the mechanism is linked to carbon-dioxide frost at these dune gullies, the same could be true for other gullies on Mars.”

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NASA Data Shed New Light About Water and Volcanoes on Mars

Copyright NASA

Data from NASA’s Phoenix Mars Lander suggest liquid water has interacted with the Martian surface throughout the planet’s history and into modern times. The research also provides new evidence that volcanic activity has persisted on the Red Planet into geologically recent times, several million years ago.

Although the lander, which arrived on Mars on May 25, 2008, is no longer operating, NASA scientists continue to analyze data gathered from that mission. These recent findings are based on data about the planet’s carbon dioxide, which makes up about 95 percent of the Martian atmosphere.

“Atmospheric carbon dioxide is like a chemical spy,” said Paul Niles, a space scientist at NASA’s Johnson Space Center in Houston. “It infiltrates every part of the surface of Mars and can indicate the presence of water and its history.”

Phoenix precisely measured isotopes of carbon and oxygen in the carbon dioxide of the Martian atmosphere. Isotopes are variants of the same element with different atomic weights. Niles is lead author of a paper about the findings published in Thursday’s online edition of the journal Science. The paper explains the ratios of stable isotopes and their implications for the history of Martian water and [...]

Missing Piece Inspires New Look at Mars Puzzle

Copyright NASA

Experiments prompted by a 2008 surprise from NASA’s Phoenix Mars Lander suggest that soil examined by NASA’s Viking Mars landers in 1976 may have contained carbon-based chemical building blocks of life.

“This doesn’t say anything about the question of whether or not life has existed on Mars, but it could make a big difference in how we look for evidence to answer that question,” said Chris McKay of NASA’s Ames Research Center, Moffett Field, Calif. McKay coauthored a study published online by the Journal of Geophysical Research – Planets, reanalyzing results of Viking’s tests for organic chemicals in Martian soil.

The only organic chemicals identified when the Viking landers heated samples of Martian soil were chloromethane and dichloromethane — chlorine compounds interpreted at the time as likely contaminants from cleaning fluids. But those chemicals are exactly what the new study found when a little perchlorate — the surprise finding from Phoenix — was added to desert soil from Chile containing organics and analyzed in the manner of the Viking tests.

“Our results suggest that not only organics, but also perchlorate, may have been present in the soil at both Viking landing sites,” said the study’s lead author, [...]

NASA’s Hibernating Mars Rover May Not Call Home

Copyright NASA

NASA mission controllers have not heard from the Mars Exploration Rover Spirit since March 22, and the rover is facing its toughest challenge yet – trying to survive the harsh Martian winter.

The rover team anticipated Spirit would go into a low-power “hibernation” mode since the rover was not able to get to a favorable slope for its fourth Martian winter, which runs from May through November. The low angle of sunlight during these months limits the power generated from the rover’s solar panels. During hibernation, the rover suspends communications and other activities so available energy can be used to recharge and heat batteries, and to keep the mission clock running.

On July 26, mission managers began using a paging technique called “sweep and beep” in an effort to communicate with Spirit.

“Instead of just listening, we send commands to the rover to respond back to us with a communications beep,” said John Callas, project manager for Spirit and its twin, Opportunity, at NASA’s Jet Propulsion Laboratory in Pasadena, Calif. “If the rover is awake and hears us, she will send us that beep.”

Based on models of Mars’ weather and its effect on available power, mission [...]

NASA Spacecraft Camera Yields Most Accurate Mars Map Ever

Copyright NASA

A camera aboard NASA’s Mars Odyssey spacecraft has helped develop the most accurate global Martian map ever. Researchers and the public can access the map via several websites and explore and survey the entire surface of the Red Planet.

The map was constructed using nearly 21,000 images from the Thermal Emission Imaging System, or THEMIS, a multi-band infrared camera on Odyssey. Researchers at Arizona State University’s Mars Space Flight Facility in Tempe, in collaboration with NASA’s Jet Propulsion Laboratory in Pasadena, Calif., have been compiling the map since THEMIS observations began eight years ago.

The pictures have been smoothed, matched, blended and cartographically controlled to make a giant mosaic. Users can pan around images and zoom into them. At full zoom, the smallest surface details are 100 meters (330 feet) wide. While portions of Mars have been mapped at higher resolution, this map provides the most accurate view so far of the entire planet.

The new map is available at: http://www.mars.asu.edu/maps/?layer=thm_dayir_100m_v11 .

Advanced users with large bandwidth, powerful computers and software capable of handling images in the gigabyte range can download the full-resolution map in sections at: http://www.mars.asu.edu/data/thm_dir_100m .

“We’ve tied the images to the cartographic control [...]

Rocky mounds and a plateau on Mars

Copyright ESA

When Mars Express set sail for the crater named after Portuguese navigator Ferdinand Magellan, it found a windblown plateau and mysterious rocky mounds nearby.

Stretching across 190 x 112 km, this region of Mars covers an area of about 21 280 sq km, which is roughly the size of Slovenia. It is located to the southwest of the volcanic region Tharsis on the southern highlands of Mars, near the crater Magellan.

Named after the famous Portuguese navigator and explorer Ferdinand Magellan, the impact crater is about 100 km across. Only a small portion of the crater rim is visible in this image, sitting at the lower right, because the Mars Express High-Resolution Stereo Camera (HRSC) has zeroed in on some intriguing features nearby.

In the west of this region (at the upper edge of the main image) there are light-coloured, irregular protrusions. These features are up to 2 km tall and are probably large rock fragments or mounds of rock. However, their formation is still debated.

One possibility is that the top layer of rock was shattered by the shockwaves from an impact. Another possible explanation would be from a process called subrosion. On [...]

Wet era on early Mars was global

Copyright ESA

Conditions favourable to life may once have existed all over Mars. Detailed studies of minerals found inside craters show that liquid water was widespread, not only in the southern highlands, but also beneath the northern plains.

ESA’s Mars Express and NASA’s Mars Reconnaissance Orbiter have discovered hydrated silicate minerals in the northern lowlands of Mars, a clear indication that water once flowed there.

The spacecraft have previously discovered thousands of small outcrops in the southern hemisphere where rock minerals have been altered by water. Many of these exist in the form of hydrated clay minerals known as phyllosilicates, and indicate that the planet’s southern hemisphere was once much warmer and wetter than it is today.

However, until this week, no sites with hydrated silicate minerals had been found in the northern lowlands, where thick blankets of lava and sediments up to several kilometres thick hamper efforts to probe the underlying bedrock.

The first hints that there may be hydrated silicates beneath the northern plains were provided by Mars Express’ OMEGA sensor. However, the outcrops were small and more detailed observations were required to confirm their presence. The OMEGA team sifted higher resolution data from [...]