Mars Meteorite Sparks New Questions About Red Planet

Designated Northwest Africa (NWA) 7034, and nicknamed "Black Beauty," the Martian meteorite weighs approximately 320 grams. (Photo: NASA)

The Martian meteorite known as “Black Beauty” weighs approximately 320 grams. (Carl Agee/University of New Mexico)

Scientists have determined a meteorite discovered in the Sahara Desert in 2011 is about 2.1 billion years old and could be the first meteorite to come from the surface of Mars.

The meteorite, designated NWA (North West Africa) 7034 and nicknamed “Black Beauty,” weighs about 320 grams and is loaded with Martian water. It is so uniquely different from other Martian meteorites that scientists say it is in a class of its own.

They believe Black Beauty, which contains 10 times more water than other Martian meteorites from unknown origins, formed during the beginning of the most recent geologic period on Mars, known as the Amazonian.

“The age of NWA 7034 is important because it is significantly older than most other Martian meteorites,” said Mitch Schulte, program scientist for the Mars Exploration Program at NASA headquarters in Washington. “We now have insight into a piece of Mars’ history at a critical time in its evolution.”

The NASA-funded team of scientists from various universities and institutions analyzed the mineral and chemical composition, age, and water content of the meteorite.

Black Beauty’s chemical composition includes organic carbon, which is similar to other Martian meteorites, known as SNC meteorites. However, other aspects of Black Beauty’s composition are very different.

“The texture of the NWA meteorite is not like any of the SNC meteorites,” said Andrew Steele, who led the carbon analysis at the Carnegie Institution’s Geophysical Laboratory. “This is an exciting measurement in Mars and planetary science. We now have more context than ever before to understanding where they may come from.”

Black Beauty, according to the research team, is made of cemented fragments of basalt, rock  formed from rapidly-cooled lava. The fragments are primarily feldspar and pyroxene, most likely from volcanic activity.

NASA Funded scientists have found that the NWA 7034 meteorite came from the surface or crust of Mars - photo taken by the Mars rover, Spirit (Photo: NASA)

Scientists say the Black Beauty meteorite came from the surface, or crust, of Mars (NASA)

“This Martian meteorite has everything in its composition that you’d want in order to further our understanding of the Red Planet,” said Carl Agee, leader of the analysis team and director and curator at the University of New Mexico’s Institute of Meteoritics in Albuquerque. “This unique meteorite tells us what volcanism was like on Mars two billion years ago. It also gives us a glimpse of ancient surface and environmental conditions on Mars that no other meteorite has ever offered.”

Up until now,  SNC meteorites have been the only meteorite samples from the Red Planet  scientists have been able to study, however, their exact point of origin on Mars isn’t  known.  Scientists say recent data from NASA Mars lander and orbiter missions indicate the SNC meteorites are actually a mismatch with the Martian crust.

But Black Beauty does match up with surface rocks and outcrops studied by NASA’s Mars rovers, such as Curiosity, Opportunity and Spirit, as well as its orbiting satellites, like the Mars Odyssey Orbiter.

“The contents of this meteorite may challenge many long-held notions about Martian geology,” said John Grunsfeld, associate administrator for NASA’s Science Mission Directorate in Washington. “These findings also present an important reference frame for the Curiosity rover as it searches for reduced organics in the minerals exposed in the bedrock of Gale Crater.”

New Microbes May Hold Clues To Extraterrestrial Life

Scanning electron micrograph of very small and numerous bacterial cells inhabiting icy brine waters in Antarctica’s Lake Vida. (Photo:  Christian H. Fritsen, Desert Research Institute)

Scanning electron micrograph of very small and numerous bacterial cells inhabiting icy brine waters in Antarctica’s Lake Vida. (Photo: Christian H. Fritsen, Desert Research Institute)

Scientists say they have found ancient microbial life in dark and very salty water some 20 meters below the surface of a frozen and isolated Antarctic lake. The finding could provide scientists with insight into how life could possibly exist in the most extreme environments on Earth as well as elsewhere throughout the cosmos.

In a study recently published in the Proceedings of the National Academy of Science (PNAS) the researchers say they took the microbes from the Antarctic’s Lake Vida, which contains no oxygen but has the highest nitrous oxide levels found in any natural bodies of water on Earth. The scientists describe the icy environment in which the sample microbes were taken as a briny liquid, about six times saltier than normal seawater and with an average temperature of minus 13.5 degrees centigrade.

“This study provides a window into one of the most unique ecosystems on Earth,” said lead author Dr. Alison Murray from the Desert Research Institute (DRI) in Reno, Nevada. “Our knowledge of geochemical and microbial processes in lightless icy environments, especially at subzero temperatures, has been mostly unknown up until now. This work expands our understanding of the types of life that can survive in these isolated, cryoecosystems (ecosystems found in ice) and how different strategies may be used to exist in such challenging environments.”

Previous studies going back to 1996 show the Lake Vida brine and its microbial residents have had to do without outside resources that normally support life (i.e.: sunlight or oxygen) for more than 3,000 years. Despite what many would consider being an unlivable habitat, the researchers in this project found that the polar lake supports what they call a surprisingly diverse and large community of bacteria that can survive the harsh conditions.

To ensure that their samples and the microbe’s ecosystem weren’t affected or contaminated by human or other external influences, the researchers developed specialized equipment and a set of very strict procedures when they set out to retrieve them during expeditions to the Antarctic back in 2005 and 2010.

Members of the 2010 Lake Vida expedition team use a sidewinder drill inside a secure, sterile tent on the lake’s surface to collect samples for their research. (Photo: Desert Research Institute, Emanuele Kuhn)

Members of the 2010 Lake Vida expedition team use a sidewinder drill inside a secure, sterile tent on the lake’s surface to collect samples for their research. (Photo: Desert Research Institute, Emanuele Kuhn)

Regarding the high levels of nitrous oxide that was found in the lakes salty water, the scientists say that geochemical analyses are suggesting that the N2O was generated by chemical reactions between the salty water and the lake’s iron-rich sediments. The chemical reaction also produced an amount of molecular hydrogen, which the researchers say may be what has been providing the energy that was needed to sustain the community of diverse microbial life.

“It’s plausible that a life-supporting energy source exists solely from the chemical reaction between anoxic salt water and the rock,” explained co-author Dr. Christian Fritsen, also from DRI.

“If that’s the case,” Murray said, “this gives us an entirely new framework for thinking of how life can be supported in cryoecosystems on earth and in other icy worlds of the universe.”

Murray said that the scientists involved with the project are continuing their research by analyzing the non-organic components, the chemical interactions between Lake Vida brine and sediment, and by using various methods of genome sequencing, and are learning more about their rare microbial find.

They also suggested the research and findings produced for this study could also provide some help to others who conduct investigations into possible cryoecosystems that might be found in the soil, sediments, wetlands, and other lakes that lie beneath the Antarctic ice sheet.

Ancient Dog Mystery Remains Unsolved

(Photo: Michael Howard via Flickr/Creative Commons)

(Photo: Michael Howard via Flickr/Creative Commons)

Exactly where man’s best friend came from remains a mystery.

Thousands of years of cross-breeding have made it difficult for scientists to trace the ancient genetic roots of today’s dogs.

Still, British researchers gave it a try. They recently compared genetic data from 1,375 modern-day dogs, from 35 different breeds, to global archeological records of dog remains.

Although, other genetic studies suggest dogs descended from the grey wolf, the researchers found modern dog breeds, genetically speaking, have little in common with their ancient ancestors.

Dogs were the first animals domesticated by man about 15,000 years ago. However, we really didn’t start keeping them as pets until about 2,000 years ago.  Even so, until fairly recently, most dogs were kept and used to perform specific jobs.

Although some dog breeds – such as the Akita, Afghan Hound and the Chinese Shar-Pei – have been classified as ancient by canine experts, they’re no closer to the first domesticated dogs than any other modern breeds.  This, according to the study, is again due to cross-breeding through the years.

Other aspects affecting the dog’s genetic diversity include human movement and migration.  Major worldwide events, such as the two world wars, also impacted the dog population, the researchers said.

Certain breeds such as the Saluki appear genetically different because they were geographically isolated and were not part of the 19th century efforts to blend lineages to create most of the breeds we keep as pets today. (Photo: Keith Dobney)

Breeds like the Saluki appear genetically different because they were geographically isolated and were not part of the 19th century efforts to blend lineages to create most of the breeds we keep as pets today. (Photo: Keith Dobney)

Lead author Greger Larson, an evolutionary biologist in Durham University’s Department of Archaeology, said, “Ironically, the ubiquity of dogs combined with their deep history has obscured their origins and made it difficult for us to know how dogs became man’s best friend.  All dogs have undergone significant amounts of cross-breeding to the point that we have not yet been able to trace all the way back to their very first ancestors.”

Previous studies of breeds such Basenjis, Salukis and Dingoes indicated they had different genetic signatures, which provided evidence of an ancient heritage.

But the researchers say their new study shows the unique genetic signatures in these dogs were not necessarily due to being directly descended from ancient dogs, but merely appeared to be genetically different because they were geographically isolated and were not part of the 19th Century kennel clubs which blended various lineages in order to create most of the breeds we’re familiar with today.

As DNA sequencing becomes faster and cheaper, the scientists are hopeful more research will provide further insight into the evolution and domestication of our canine friends.

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