‘Black Beauty’ found in Sahara could yield Martian secrets

Updated 05 January 2013
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‘Black Beauty’ found in Sahara could yield Martian secrets

WASHINGTON: A fist-sized meteorite nicknamed “Black Beauty” could unlock vital clues to the evolution of Mars from the warm and wet place it once was to its current cold and dry state, NASA said Thursday.
Discovered in Morocco’s Sahara Desert in 2011, the 11-ounce (320-gram) space rock contains 10 times more water than other Martian meteorites and could be the first ever to have originated on the planet’s surface or crust.
After more than a year of intensive study, a team of US scientists determined the meteorite formed 2.1 billion years ago during the beginning of the most recent geologic period on Mars, known as the Amazonian, NASA said.
The abundance of water molecules in the meteorite — about 6,000 parts per million, 10 times more than other known rocks — suggests water activity persisted on the Martian surface when it was formed.
It is generally accepted that Mars had abundant water early in its existence — scientists ponder if life might once have existed there — but the nature of its evolution to a cold and dry place remains a mystery.
“Many scientists think that Mars was warm and wet in its early history, but the planet’s climate changed over time,” lead scientist Carl Agee, whose study was published in “Science Express,” told Space.com.
Known technically as NWA (Northwest Africa) 7034, “Black Beauty” is made of cemented fragments of basalt, a rock that forms from rapidly cooled lava.
“Perhaps most exciting is that the high water content could mean there was an interaction of the rocks with surface water either from volcanic magma, or from fluids from impacting comets during that time,” co-author Andrew Steele said.
“It is the richest Martian meteorite geochemically and further analyzes are bound to unleash more surprises.”
Unlike most Martian meteorites, it is thought to be from the planet’s surface, not deeper inside, as its chemistry matched surface rocks NASA has studied remotely via Mars rovers and orbiting satellites.
“Researchers theorize the large amount of water contained in NWA 7034 may have originated from interaction of the rocks with water present in Mars’ crust,” NASA said.
“The meteorite also has a different mixture of oxygen isotopes than has been found in other Martian meteorites, which could have resulted from interaction with the Martian atmosphere.”
More than 100 Martian meteorites have been discovered on Earth to date but most come from three meteorites: Shergotty, Nakhla, and Chassigny.
NWA 7034 has unique characteristics and it took scientists several months to ascertain that it did indeed come from Mars and not another planet, or from an asteroid belt.
“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.”
Agee echoed those comments.
“This Martian meteorite has everything in its composition that you’d want in order to further our understanding of the Red Planet,” he said, noting that it “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,” Agee added. It was not until the 1980s that scientists were able to determine the origin of meteorites by analyzing small pockets of atmospheric gas trapped inside.
Gases are released by heating the rock in a laboratory and then analyzed and compared, in this case, to the information gathered by probes orbiting Mars or on its surface.
The latest probe, the Curiosity rover — the most sophisticated ever sent to another planet — has since August been searching for signs the planet was ever suitable for microbial life.
“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.”


San Francisco restaurants open kitchens to refugee chefs

Updated 10 min 47 sec ago
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San Francisco restaurants open kitchens to refugee chefs

  • The Refugee Food Festival started in Paris in 2016 and came to the US for the first time this year
  • The program lets refugees aspiring to be chefs work in professional kitchens

SAN FRANCISCO: At San Francisco’s Tawla restaurant, Muna Anaee powdered her hands with flour and gently broke off a piece of golden dough to prepare bread eaten in Iraq, the country she fled with her family.
Anaee was preparing more than 100 loaves for diners Wednesday night as part of a program that lets refugees aspiring to be chefs work in professional kitchens.
The Refugee Food Festival — a joint initiative of the United Nations Refugee Agency and a French nonprofit, Food Sweet Food — started in Paris in 2016 and came to the US for the first time this year, with restaurants in New York participating as well. The establishments’ owners turn over their kitchens to refugee chefs for an evening, allowing them to prepare sampling platters of their country’s cuisine and share a taste of their home.
Restaurants in 12 cities outside the US are taking part in the program this month.
“It’s been a big dream to open a restaurant,” said Anaee, 45, who now has a green card.
Anaee was among five refugees chosen to showcase their food in San Francisco — each at a different restaurant and on a different night, from Tuesday through Saturday. Organizers say the goal is to help the refugees succeed as chefs and raise awareness about the plight of refugees worldwide.
It’s important to “really get to know these refugees and their personal stories,” said Sara Shah, who brought the event to California after seeing it in Belgium.
Anaee and her husband and two children left Baghdad in 2013 over concerns about terrorism and violence. She worked as a kindergarten teacher in Iraq, not a chef, but was urged to pursue cooking as a career by peers in an English class she took in California after they tasted some of her food.
Azhar Hashem, Tawla’s owner, said hosting Anaee was part of the restaurant’s mission to broaden diners’ understanding of the Middle East — a region that inspires some of its dishes.
“Food is the best — and most humanizing — catalyst for having harder conservations,” she said.
The four other aspiring chefs serving food in San Francisco are from Myanmar, Bhutan, Syria and Senegal.
Karen Ferguson, executive director of the Northern California offices of the International Rescue Committee, said San Francisco was a good city for the food festival.
“We have so much diversity, and we see the evidence of that in the culinary expertise in the area,” she said.
The Bay Area has a high concentration of refugees from Afghanistan, Honduras, Guatemala, El Salvador, Eritrea and Burma, though exact numbers are unclear, according to the rescue committee. Its Oakland office settled more than 400 refugees in the Bay Area last year, but the number of refugees settling in the region has fallen dramatically since the Trump administration this year placed a cap on arrivals, Ferguson said.
Pa Wah, a 41-year-old refugee from Myanmar, presented dishes at San Francisco’s Hog Island Oyster Co. on Tuesday. She said she didn’t consider a career in cooking until she moved to California in 2011 and got her green card.
Cooking was a means of survival at the Thailand refugee camp where she lived after escaping civil conflict in Myanmar as a child. Participating in the food festival showed her the challenges of running a restaurant, but also helped her realize she was capable of opening her own, she said.