team of NASA and university scientists has achieved the first definitive detection of methane in the atmosphere of Mars. This discovery indicates the planet is either biologically or geologically active. The team found methane in the Martian atmosphere by carefully observing the planet throughout several Mars years with NASA’s Infrared Telescope Facility and the W.M. Keck telescope, both at Mauna Kea, Hawaii. The team used spectrometers on the telescopes to spread the light into its component colors, as a prism separates white light into a rainbow. The team detected three spectral features called absorption lines that together are a definitive signature of methane.
January 13th, 2009
Wind-driven reorganization of coarse clasts on the surface of Mars Geology
Coarse (pebble to cobble sized) clasts on the intercrater plains of the Mars Exploration Rover Spirit landing site exhibit a nonrandom (i.e., uniformly spaced) distribution. This pattern has been attributed to the entrainment and redistribution of coarse clasts during extreme wind events. Here we propose an alternative mechanism readily observable in wind tunnels and numerical models at modest wind speeds. In this process, coarse clasts modify the air flow around them, causing erosion of the underlying substrate on the windward side and deposition on the leeward side until a threshold bed-slope condition is reached, after which the clast rolls into the windward trough. Clasts can migrate across an erodible substrate in repeated cycles of trough formation and clast rolling, “attracting” or “repelling” one another through feedbacks between the local clast density, substrate erosion and/or deposition rate, and substrate elevation. The substrate beneath areas of locally high clast densities aggrades, building up a topographic high that can cause clasts to repel one another to form a more uniform distribution of clasts through time. This self-organized process likely plays a significant role in the evolution of mixed grain size eolian surfaces on Earth and Mars.
November 24th, 2008
Mars Express observes aurorae on the Red Planet
Scientists using ESA’s Mars Express have produced the first crude map of aurorae on Mars. These displays of ultraviolet light appear to be located close to the residual magnetic fields generated by Mars’s crustal rocks. They highlight a number of mysteries about the way Mars interacts with electrically charged particles originating from the Sun.
The aurorae on Mars were discovered in 2004 using the SPICAM ultraviolet and infrared atmospheric spectrometer on board Mars Express. They are a powerful tool with which scientists can investigate the composition and structure of the Red Planet’s atmosphere.
November 21st, 2008
Buried Glaciers Found on Mars
Mars has vast glaciers hidden under aprons of rocky debris near mid-latitude mountains, a new study confirms, pointing to a new and large potential reservoir of life-supporting water on the planet.
These mounds of ice exist at much lower latitudes than any ice previously found on the red planet.
“Altogether, these glaciers almost certainly represent the largest reservoir of water ice on Mars that’s not in the polar caps,” said John Holt of the University of Texas at Austin and the main author of the study. “Just one of the features we examined is three times larger than the city of Los Angeles and up to one-half-mile thick, and there are many more.”
September 30th, 2008
Phoenix lander spots falling snow on Mars
NASA’s Phoenix spacecraft has discovered evidence of past water at its Martian landing site and spotted falling snow for the first time, scientists reported Monday. Soil experiments revealed the presence of two minerals known to be formed in liquid water. Scientists identified the minerals as calcium carbonate, found in limestone and chalk, and sheet silicate.
But exactly how that happened remains a mystery.
“It’s really kind of all up in the air,” said William Boynton, a mission scientist at the University of Arizona at Tucson.
A laser aboard the Phoenix recently detected snow falling from clouds more than two miles above its home in the northern arctic plains. The snow disappeared before reaching the ground.
September 27th, 2008
Signs of Underground Plumbing Seen on Mars
A NASA probe has spotted hundreds of small surface fractures near Mars’ equator that may have acted as underground natural plumbing to channel groundwater billions of years ago.
Geologists compare the fractures in the sandstone rock deposits on Mars to features called deformation bands on Earth, which can arise from the influence of groundwater in the underground bedrock. The bands and faults have strong influences on groundwater movement on Earth, and seem to have played the same role on Mars. Other research has examined how surface water from rain or snow shaped the planet surface, but many agree that groundwater has an equally important influence.
“Groundwater often flows along fractures such as these, and knowing that these are deformation bands helps us understand how the underground plumbing may have worked within these layered deposits,” said Chris Okubo, a geologist with the U.S. Geological Survey in Flagstaff, Ariz. who headed up a new study of the Martian fractures.
August 5th, 2008
Scientists debate the meaning of mineral found on Mars Arizona Daily Star
The unanticipated discovery of a mineral in Mars’ arctic soil doesn’t rule out the possibility that the red planet could support life, scientists with the Phoenix lander said today.
While cautioning that the discovery of perchlorate, an oxidizing agent found in rocket fuel, still had to be confirmed by more experiments, scientists with the UA-led Phoenix Mars Mission rejected speculation that the mineral’s presence killed the possibility of life on the planet.
“These compounds are quite stable and don’t destroy organic compounds,” said Peter Smith, the UA’s lead scientist for the mission. “This is an important piece in the puzzle and it is neither good nor bad for life.” While perchlorate can be hazardous to some life forms on Earth, others use the molecules for life, including in remote arid desert regions.
“The interesting thing is perchlorate is a relatively inert oxidant,” said Richard Quinn, a mission scientist. “There are some microbes that use it as an energy source.”
July 19th, 2008
How Mars and Alaska Are Alike
Little did Bucknell University geology professors Craig Kochel and Jeffrey Trop know, as they were working in Alaska, that they would soon predict one of the most important planetary observations ever made.
The pair was in Alaska for an eight-day trip in July 2006, studying geological features and the processes that create them. As they studied photographs taken of the surrounding area, some features caught Kochel’s eye. He thought they were strangely familiar, and then realized they reminded him of images he’d seen when working on the Viking missions to Mars in the 1970s.
Kochel and Trop trekked to where the shots were taken overlooking a glacier. Spotting triangle-shaped landforms called “fans” sealed the deal: They looked strikingly similar to photographs taken of features on Mars.
June 27th, 2008
Ground Control to Farmer Tom: asparagus on Mars? The Times
If there ever was, is, or will be, life on Mars, it had better like eating asparagus.
Nasa scientists who have reviewed the results of the first analysis of soil collected by the Phoenix Mars lander say they were ‘flabbergasted’ to find that it contained all the basic requirements, in terms of minerals and nutrients, to sustain life on the Red Planet.
It was also much less acidic than the experts had expected – and suprisingly similar to garden dirt back on Earth.
“There is nothing about the soil that would preclude life. In fact it seems very friendly,” said Professor Samuel Kounaves of Tufts University, the project’s lead chemist, told reporters in a telephone conference. “The soil you have there is the type of soil you have in your backyard,” he added. “You may be able to grow asparagus very well.”
June 26th, 2008
Martian air once had moisture, new soil analysis says UC Berkeley
A new analysis of Martian soil data led by University of California, Berkeley, geoscientists suggests that there was once enough water in the planet’s atmosphere for a light drizzle or dew to hit the ground, leaving tell-tale signs of its interaction with the planet’s surface. The study’s conclusion breaks from the more dominant view that the liquid water that once existed during the red planet’s infancy came mainly in the form of upwelling groundwater rather than rain. To come up with their conclusions, the UC Berkeley-led researchers used published measurements of soil from Mars that were taken by various NASA missions: Viking 1, Viking 2, Pathfinder, Spirit and Opportunity. These five missions provided information on soil from widely distant sites surveyed between 1976 and 2006.