NASA Orbiter Reveals Big Changes in Mars' Atmosphere

A newly found, buried deposit of frozen carbon dioxide - dry ice - near the south pole of Mars contains about 30 times more carbon dioxide than previously estimated to be frozen near the pole.

by Staff Writers Pasadena CA (JPL) Apr 25, 2011

NASA's Mars Reconnaissance Orbiter has discovered the total amount of atmosphere on Mars changes dramatically as the tilt of the planet's axis varies. This process can affect the stability of liquid water, if it exists on the Martian surface, and increase the frequency and severity of Martian dust storms. Researchers using the orbiter's ground-penetrating radar identified a large, buried deposit of frozen carbon dioxide, or dry ice, at the Red Planet's south pole. The scientists suspect that much of this carbon dioxide enters the planet's atmosphere and swells the atmosphere's mass when Mars' tilt increases. The findings are published in this week's issue of the journal Science.
The newly found deposit has a volume similar to Lake Superior's nearly 3,000 cubic miles (about 12,000 cubic kilometers). The deposit holds up to 80 percent as much carbon dioxide as today's Martian atmosphere. Collapse pits caused by dry ice sublimation and other clues suggest the deposit is in a dissipating phase, adding gas to the atmosphere each year. Mars' atmosphere is about 95 percent carbon dioxide, in contrast to Earth's much thicker atmosphere, which is less than .04 percent carbon dioxide.

US Space Wing sharpens focus on contested environment

A graphic depicting satellites and their orbits demonstrates how the space around Earth is contested and congested.

by Staff Writers Schriever AFB CO (SPX) Apr 25, 2011

During the summer of 1861, a pair of competing visionaries ushered in the concept of aerial reconnaissance when they successfully piloted gas-filled balloons hundreds of feet into the air. In separate events, John LaMountain and Thadeus Lowe viewed Confederate troop encampments and reported their findings to Union Army officers. As soon as Confederate soldiers learned their adversaries had developed eyes in the sky, they quickly developed strategies to shoot them down - ushering in the concept of contested air space.
While time and technology have served to transform the domains of contention, 150 years later the notions of contested space and cyberspace have become such strategically important concepts that the 50th Space Wing Commander, Col. Wayne Monteith, included them in the wing's revised vision statement. The terms have also been accentuated in the Air Force motto.
"It's about recognition," said Col. Michael Finn, commander, 50th Network Operations Group. "We enable information for the warfighter and national security decision makers. So we have to recognize a shift in thinking about the information domain, from one that is support centric, to one that is about preserving our freedom of action in the domain, while denying our adversary the same when called upon to do so."

Satellites track human rights abuses

Washington DC, US

Satellites images can help track human rights abuses from around the world, according to researchers who believe that this technology could one day help prevent such atrocities.

US researcher Lars Bromley proved its effectiveness when he watched the final days of the Sri Lankan conflict unfold with the help of satellites. Bromley observed the digital satellite photos as part of the Science and Human Rights Program at the American Association for the Advancement of Science (AAAS). This has been reported by Christian Science Monitor.

Bromley, a geographer, wanted to determine if the Sri Lankan Army was attacking a civilian safety zone during the war against the Tamil Tiger rebels in May 2009. Since the photos were not sufficiently fine-grain to reveal corpses, Bromley and his team focused on other damage like shattered buildings and mortar craters in places where refugees had previously gathered. The rectangular grids of Tamil Tiger cemeteries grew every day in the new photos, revealing dozens of new graves. The Sri Lankan government denied targeting civilian areas.

One of Bromley's team members who studied meteor craters on Mars noticed sprays of soil kicked up from mortar craters. The orientation of those sprays allowed him to extrapolate the trajectory of incoming shells - and ultimately, trace them back to Sri Lankan Army positions.

AAAS has also documented home demolitions by Zimbabwean leader Robert Mugabe's regime in its first satellite project in 2005. Burning of hundreds of villages in Darfur was revealed in a 2007 project. Others have probed abuses in Myanmar, Gaza, North Korea, Ethiopia, and the Democratic Republic of Congo.

Patrick Meier, a visiting scholar at Stanford University, in California, who co-founded the global network Crisis Mappers, said: "You're not just documenting human rights abuses so you can bring someone to justice in The Hague three years later." The question is "can you provide tactical data for people to act on and get out of harm's way?", the Monitor quoted him as saying.

Source: http://www.geospatialworld.net