NASA Spacecraft Detects Impact Glass on Surface of Mars

Researchers have found deposits of impact glass (in green) preserved in Martian craters, including Alga Crater, shown here. The detection is based on data from the instrument Compact Reconnaissance Imaging Spectrometer for Mars (CRISM) on NASA's Mars Reconnaissance Orbiter.
Credits: NASA/JPL-Caltech/JHUAPL/Univ. of ArizonaNASA's Mars Reconnaissance Orbiter (MRO) has detected deposits of glass within impact craters on Mars. Though formed in the searing heat of a violent impact, such deposits might provide a delicate window into the possibility of past life on the Red Planet.

During the past few years, research has shown evidence about past life has been preserved in impact glass here on Earth. A 2014 study led by scientist Peter Schultz of Brown University in Providence, Rhode Island, found organic molecules and plant matter entombed in glass formed by an impact that occurred millions of years ago in Argentina. Schultz suggested that similar processes might preserve signs of life on Mars, if they were present at the time of an impact.

Fellow Brown researchers Kevin Cannon and Jack Mustard, building on the previous research, detail their data about Martian impact glass in a report now online in the journal Geology.

“The work done by Pete and others showed us that glasses are potentially important for preserving biosignatures,” Cannon said. “Knowing that, we wanted to go look for them on Mars and that’s what we did here. Before this paper, no one had been able to definitively detect them on the surface.”

Cannon and Mustard showed large glass deposits are present in several ancient, yet well-preserved, craters on Mars. Picking out the glassy deposits was no easy task. To identify minerals and rock types remotely, scientists measured the spectra of light reflected off the planet’s surface. But impact glass doesn’t have a particularly strong spectral signal.

“Glasses tend to be spectrally bland or weakly expressive, so signature from the glass tends to be overwhelmed by the chunks of rock mixed in with it,” said Mustard. “But Kevin found a way to tease that signal out.”

In a laboratory, Cannon mixed together powders with a similar composition of Martian rocks and fired them in an oven to form glass. He then measured the spectral signal from that glass.

Once Mustard had the signal from the lab glass, he used an algorithm to pick out similar signals in data from MRO’s Compact Reconnaissance Imaging Spectrometer for Mars (CRISM), for which he is the deputy principal investigator.

The technique pinpointed deposits in several Martian crater central peaks, the craggy mounds that often form in the center of a crater during a large impact. The fact the deposits were found on central peaks is a good indicator that they have an impact origin.

Knowing that impact glass can preserve ancient signs of life -- and now knowing that such deposits exist on the Martian surface today -- opens up a potential new strategy in the search for ancient Martian life.

“The researchers’ analysis suggests glass deposits are relatively common impact features on Mars,” said Jim Green, director of NASA’s planetary science division at the agency’s headquarters in Washington. “These areas could be targets for future exploration as our robotic scientific explorers pave the way on the journey to Mars with humans in the 2030s.”

One of the craters containing glass, called Hargraves, is near the Nili Fossae trough, a 400-mile-long (about 650-kilometer-long) depression that stretches across the Martian surface. The region is one of the landing site contenders for NASA’s Mars 2020 rover, a mission to cache soil and rock samples for possible return to Earth.

Nili Fossae trough is already of scientific interest because the crust in the region is thought to date back to when Mars was a much wetter planet. The region also is rife with what appear to be ancient hydrothermal fractures, warm vents that could have provided energy for life to thrive just beneath the surface.

“If you had an impact that dug in and sampled that subsurface environment, it’s possible that some of it might be preserved in a glassy component,” Mustard said. “That makes this a pretty compelling place to go look around, and possibly return a sample.”

MRO has been examining Mars with CRISM and five other instruments since 2006.

"This significant new detection of impact glass illustrates how we can continue to learn from the ongoing observations by this long-lived mission," said Richard Zurek, MRO project scientist at NASA's Jet Propulsion Laboratory (JPL) in Pasadena, California.

The Johns Hopkins University Applied Physics Laboratory in Laurel, Maryland, provided and operates CRISM. JPL manages MRO for NASA's Science Mission Directorate in Washington. Lockheed Martin Space Systems in Denver built the orbiter and supports its operations.
Bron:http://www.nasa.gov/press-release/nasa-spacecraft-detects-impact-glass-on-surface-of-mars

NASA Seeks Ideas for Where on Mars the Next Giant Leap Could Take Place

NASA is advancing the Journey to Mars by starting the conversation about where humans may one day land on the Red Planet. The agency is hosting a conference this fall to collect proposals on areas on Mars that would be of high scientific research value while also providing natural resources to enable human explorers to safely land, live and work on Mars. 

NASA's first Landing Site/Exploration Zone Workshop for Human Missions to the Surface of Mars will be held Oct. 27-30 at the Lunar and Planetary Institute in Houston. The conference will start the process for choosing sites on Mars that NASA's Mars Reconnaissance Orbiter and Mars Odyssey spacecraft along with any future missions over the coming decades could then further image to create better maps and provide valuable scientific data of these potential Exploration Zones.

NASA hopes to engage scientists, technologists and experts in human exploration during the conference, fostering collaboration among the teams that will enable humans to live on and explore Mars in the coming decades.

Potential "Exploration Zones" will need to offer compelling science research while also providing resources that our astronauts can take advantage of during their pioneering of the Red Planet. First explorers are expected to be limited to about 60 miles (100 km) of travel from their landing site due to life support and exploration technology requirements. 

The life expectancy of the existing MRO and Odyssey spacecraft being limited, NASA is eager to take advantage of the remaining operational years of those Martian imagers to gather high resolution maps of potential exploration zones while the spacecraft, already well beyond their design lifetime, are still operational.

NASA’s efforts for building the knowledge and capabilities for sending humans to Mars is underway today, with spacecraft monitoring Mars from orbit and rovers on the surface, the International Space Station being used to test systems and to learn more about the health impacts of extended space travel, and the development and testing of the next generation of launch and crew vehicles -- the Space Launch System rocket and Orion crewed spacecraft underway

As we explore the path to Mars, we gain new knowledge and capabilities that will make life better here on Earth, right now. This preliminary work on potential landing sites will facilitate dialogue about this next giant leap in human experience.
Bron:http://www.nasa.gov/journeytomars/mars-exploration-zones | Gewijzigd: 1 februari 2017, 13:39 uur, door Joyce.s