NEW BEAUTY FOUND ON MARS
We’re blown away by what looks like a hurricane, tens of thousands of miles away. Reminiscent of the cottony swirls we see in weather satellite photos, this composite image of Mars’s north polar ice cap, looks like an abstract golden hurricane swirling around its eye. The image, released just now to mark the tenth anniversary of the European Space Agency’s June 2003 launch, is made up of 57 separate photos, taken by ESA's high resolution stereo camera, as it orbited the planet 300-500 km above its surface, during the course of the Mars Express Mission.
The ice cap is approximately 1000 km in diameter and is made up of layers of dusty ice, which are, together, about 2 km thick, and covered by a mercurial frosting of carbon dioxide ice, waxing and waning between Martian winters and summers. The spirals you see, spinning out from the center of the cap, are said to be caused by whirling Martian winds, gouging troughs through the cap’s layers.
Beyond its high resolution cameras, Mars Express came loaded and ready with an awesome toolbox, containing sophisticated spectrometers and radar, enabling it to study a full range of Martian atmosphere and climate, as well as surface and subsurface mineralogy and geology. The color-coded image above, originally taken this past January (2013), shows the varying depths of the twin Arima craters in Mars’s Thaumasia Planum region.
During its 10-year Martian adventure, Mars Express served up 10 major accomplishments, including the first detection of hydrated minerals to the discovery of glacial land formations, the largest volcanoes found in our solar system, and localized auroras.
NASA’s twin robot geologists, the Mars Exploration Rovers, also launched in 2003, have complemented the Mars Express mission in the pioneering explorations of Mars. While one rover, the Spirit, got stuck and ceased to operate in 2010, the solar-powered Opportunity rover has long outlived its original life expectancy to produce an invaluable cache of data and images that reveal the beautiful evolution of this red planet. During its 10-year tenure, the Opportunity has discovered numerous pieces of evidence pointing to water once present on Mars, however the samples were highly acidic, and not conducive to life, as we know it.
Last month, the most exciting Opportunity discovery yet is of a mineral-laden clay deposit, called, “Esperance,” on the rim of “Endeavor,” the largest of five Martian craters investigated by the rovers. It is the first evidence of pH-neutral water, the kind of water with prebiotic chemistry that could very well have led to the origin of life about three and a half billion years ago. “This is water you can drink,” says Steven W. Squyres, the principal investigator in the project.
Aluminum, calcium, and magnesium deposits, gathered and analyzed by Opportunity’s rock abrasion tool, alpha particle X-ray spectrometer, and microscope, were likely formed as water rushed over volcanic rocks. These rocks are similar to those usually laid down in riverbeds. “This is powerful evidence that water interacted with this rock and changed its chemistry, changed its mineralogy in a dramatic way,” explained Squyres.
The image above is a composite of the 817 photos, taken by the Opportunity rover, while it rested, soaking up the diluted sun in order to recharge its batteries, at the edge of the Endeavor crate, during the 6-month Martian winter last year.
The Opportunity will attempt to survive another Martian winter, which will begin in February, 2014, as it travels to Solander Point, a hill less than a mile away from the Endeavor crater, where the hill’s steep slope will tilt the rover’s solar panels northward, towards the sun, and, hopefully enabling it to capture more enlightening images from the surrounding landscape.
The image above, taken by Opportunity, shows “soft” rock, with a high sulfur content, another indication of water passing through.
While the Opportunity’s capabilities are primarily limited to detecting carbon-based molecules, key building blocks of life, NASA’s newest rover, the Curiosity, which landed on another part of Mars, last August (2012), is larger and has a much more sophisticated chemistry lab on board.
In its relatively short line of duty, Curiosity has also confirmed there was once fresh water on the surface of Mars. Curiosity’s first analysis of powder drilled from an ancient mudstone showed signs of pH-neutral water, plus elements needed to support microbial life. Results from the rover’s second sample analysis are pending. Curiosity has the additional advantage of being powered by a thermoelectric nuclear battery, which will enable it to operate for several decades without having to recharge.
According to an article published in Nature Geoscience magazine (2010), data from the NASA rovers and the ESA satellite led geoscientists from Colorado University to conclude that more than one third of Mars’s surface was covered by water about 3 billion years ago.
You can follow the rovers’ journeys on these maps published by NASA Jet Propulsion Laboratory at California Institute of Technology.
When we see the red ball hanging low in our terrestrial horizon, it is beautiful enough. But, thanks to our latest abilities to see it more closely and deeply, Mars is looking way more beautiful now.
