Wolves striker Raul Jimenez has surgery on a fractured skull suffered in a clash of heads during his side's Premier League win at Arsenal.(2020/11/30 20:53)
Voice of America is an international news and broadcast organization serving Central and Eastern Europe, the Caucasus, Central Asia, Russia, the Middle East and Balkan countries
Learning English use a limited vocabulary and are read at a slower pace than VOA's other English broadcasts. Previously known as Special English.(2020/11/30 09:30)
New research suggests huge floods once flowed through an area on Mars. Scientists say the finding could be a new sign that the planet may have once had the right conditions to support some form of life.
The evidence comes from data collected by NASA’s Curiosity rover, an exploration vehicle. Curiosity landed on Mars in 2012 and has been exploring the planet’s Gale Crater ever since. Scientists believe Gale Crater was formed when a meteor hit Mars in its early history, about 3.5 to 3.8 billion years ago.
Scientists have already collected evidence suggesting that Mars once had a lot of water. In 2015, NASA’s Curiosity team said the rover had gathered evidence showing that the Red Planet could have stored water in large lakes billions of years ago.
Last year, European researchers reported that they had discovered the first evidence of a huge groundwater system that once existed below the surface of Mars. Another study from 2019 suggested that Gale Crater was also once home to a number of large, salty lakes.
Scientists have long linked the complex history of water on Mars to whether or not life ever existed on the planet.
The evidence that supported the earlier findings is similar to the latest evidence provided by the NASA rover. The data centers on formations - made by water and sediment – observed by Curiosity in the Gale Crater.
But the new findings, described in a study appearing in Nature Scientific Reports, suggest that huge “megafloods” once flowed through the area.
What caused “megafloods?”
Alberto G. Fairén is a visiting astrobiologist at New York’s Cornell University. He helped lead the research and was a co-writer of the study.
“We identified megafloods for the first time using detailed sedimentological data observed by the rover Curiosity,” he said in a statement. Fairén added that such deposits, “left behind by megafloods,” had not been identified by any past Mars observations.
The scientists believe the most likely cause of huge Mars flooding “was the sudden heat produced by a large impact,” the study states. Heat from the meteor hit likely caused melting ice from frozen bodies of water to release carbon dioxide and methane into the atmosphere.
The study suggests this event led to a temporary change on Mars from a cold, dry climate to a warm, wet period. This led to extended, heavy rainfall across the planet. This water “combined with water roaring down from (a mountain inside Gale Crater) to cause gigantic flash floods,” the study said.
The evidence includes Curiosity observations of large, wave-shaped elements in sedimentary layers of the Gale Crater. The researchers describe these elements as “antidunes,” small sand hills that form from water flows. The observed antidunes were about 9 meters high and spaced about 137 meters apart, said Ezat Heydari. He is a professor of physics at America’s Jackson State University in Mississippi and a co-writer of the study.
Heydari said the antidunes are evidence of flowing megafloods at the bottom of the Gale Crater about 4 billion years ago. He noted that they are exactly like elements formed by melting ice on Earth about 2 million years ago.
Growing evidence of a habitable planet
Cornell’s Fairén said the evidence from early Mars suggests that geologically, it was “an extremely active planet.” Mars “had the conditions needed to support the presence of liquid water on the surface,” he added.
The latest study adds to growing evidence that Mars had the conditions to be a habitable planet. Fairén says scientists will now attempt to uncover evidence that it was, in fact, inhabited.
He noted such evidence could come from NASA’s newest rover, Perseverance. The Mars explorer – which NASA calls its brainiest rover yet – launched into space on July 30.
Perseverance, which will aim to search for new signs of life on Mars, is set to reach the planet’s Jezero Crater in February 2021.
I’m Bryan Lynn.
Bryan Lynn wrote this story, based on reports from Cornell University, Nature Scientific Reports and NASA. Hai Do was the editor.
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crater – n. a large round hole in the ground made by the explosion of a bomb or by something falling from the sky
meteor – n. a rock from outer space that becomes very hot and burns brightly in the sky as it enters Earth's atmosphere
sediment – n. a solid substance that forms a layer at the bottom of a liquid
megaflood – n. a large, catastrophic flood
deposit – n. a layer of a substance that has developed from a natural or chemical process
impact – n. ta powerful effect something has on a particular person or situation
roar – v. moving fast and in a powerful way
gigantic – adj. very large
geologic – adj. the study of the rocks and similar substances that make up the Earth's surface
habitable – adj. able to support life (2020/11/30 07:02)
People who have had COVID-19 are unlikely to get the disease again for at least six months after their first infection, new research suggests.
Researchers studied 12,219 British healthcare workers involved in treating people infected with the new coronavirus. COVID-19 is the disease caused by that virus.
The findings could be important for tens of millions of people worldwide who have been infected, researchers at the University of Oxford said.
“This is really good news, because we can be confident that, at least in the short term, most people who get COVID-19 won’t get it again,” said David Eyre. He was one of the leaders of the study.
Rare cases of re-infection had caused concern that immunity from the virus might not last and that recovered patients might get sick again.
But the results of the study suggest cases of reinfection are likely to remain extremely rare. The study was carried out on healthcare workers who are among those at highest risk of getting COVID-19.
“Being infected with COVID-19 does offer protection against re-infection for most people for at least six months,” Eyre said. “We found no new symptomatic infections” in any of the workers who had tested positive for antibodies.
The study is part of a major employee testing program. It covered a 30-week period between April and November 2020. The results have not yet been studied and confirmed by other scientists but were published early on the website MedRxiv.
During the study, 89 of 11,052 healthcare workers without antibodies got a new infection with symptoms. However, none of the 1,246 workers with antibodies got a symptomatic infection.
The workers with antibodies were also less likely to test positive for COVID-19 without symptoms, the researchers said. Seventy-six of them without antibodies tested positive, compared to three with antibodies. Those three are all well and did not get COVID-19 symptoms, they added.
Eyre told Reuters news agency that the researchers would keep watching the workers carefully “to see how long protection lasts.” And they will watch to see whether an earlier infection affects the severity of a new infection.
I’m Alice Bryant.
Reuters news agency reported this story. Alice Bryant adapted it for Learning English. Mario Ritter, Jr. was the editor.
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Words in This Story
confident –adj. have the belief that something will happen or is true
immunity –n. protection from being affected by infectious disease
symptomatic –adj. showing that a disease is present, showing signs of disease
positive –adj. showing that a chemical, substance or germ is present(2020/11/30 06:58)
America’s first restaurant was called Delmonico’s. It started in 1830 in New York. And Yale University history professor Paul Freedman says it had a big effect on the food Americans eat.
“It defined what elegant food was in the 19th century United States, and that has influenced…the food that is eaten today,” Freedman said.
Delmonico’s invented famous foods like lobster Newberg and baked Alaska. It continues to serve those and other favorites at its New York City location.
“It's created in the 1830s, but in 1890, it's still considered the best restaurant in the U.S.,” Freedman said. A lot of restaurants elsewhere called themselves “the Delmonico's of” whatever city they were in, he added.
In his book, “Ten Restaurants That Changed America,” Freedman names nine other restaurants that greatly influenced what Americans eat.
“I chose them both for just the delight of restaurants as places, but also as a way of talking about American history,” he says. “Because you can't talk about restaurants without talking about ethnicity, immigration…and different social settings. So, this was intended… as a history of American society seen through its restaurants.”
Howard Johnson’s is on the list. It was one of America’s first chain restaurants. A chain restaurant provides exactly the same food selections no matter which restaurant a person visits.
Howard Johnson’s were built along highways. “It was roadside food. It was chain food. It pioneered the franchise as a way of expansion, Freedman said. The company’s founder, Howard Deering Johnson, built his restaurants so that drivers could easily identify them, he added.
Howard Johnson’s did not survive the competition it helped create, like McDonald’s and other fast-food restaurants.
Also on the list is the Mandarin, a Chinese restaurant opened in San Francisco in 1961 by Cecilia Chang. She remade Americans’ idea of Chinese food, making it luxurious, Freedman said.
Other women-run restaurants Freedman writes about include Sylvia’s in Harlem. Born in South Carolina, Sylvia Woods brought Southern cooking and the idea of a neighborhood restaurant as a community gathering place to New York.
It “is also an example of the story of African American migration from the South to the North,” Freedman said.
Mamma Leone’s, also in New York, helped bring Italian food to the American people. Luisa Leone opened her eatery in 1906 and was able to expand beyond Italian American diners. She created a model for other immigrant business owners to follow.
“Mamma Leone’s served something like 3,000 people a day, many of them tourists, so a lot of people got their idea of what Italian food ought to be,” Freedman said.
Alice Waters opened Chez Panisse in Berkeley, California, in 1971. She changed American cooking by using only local and in-season foods - a tradition that continues today.
Although these female restaurateurs served widely different foods, they all created restaurants that valued quality food.
It “was familiar but better,” Freedman said. “Better than the competition."
The other restaurants on Freedman’s list include The Four Seasons in New York. It opened in 1959 and offered American food at a time when French food was popular.
He includes Le Pavillon in New York, Antoine’s in New Orleans and Schrafft’s in Boston.
Most of Freedman’s picks are on the East or West Coast.
“I think it has to do with New York and San Francisco being ports, and so, the first place where immigrants opened up restaurants,” he said.
I’m Jill Robbins.
VOA’s Dora Mekouar reported this story. Susan Shand adapted it for Learning English. Bryan Lynn was the editor.
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Words in This Story
elegant – adj. showing good taste : graceful and attractive
delight – n. a strong feeling of happiness
pioneer – v. a person who helps create or develop new ideas, methods
franchise – n. the right to sell a company's goods or services in a particular area
luxurious – adj. very comfortable and expensive
tourist– n. one who visits a place for pleasure
familiar – adj. frequently seen, heard, or experienced (2020/11/30 06:57)
Children around the world can rejoice. Santa Claus will follow his yearly path and give presents to good children everywhere this Christmas. The worldwide pandemic will not interfere.
In traditional stories, Santa Claus is a happy old man who gives gifts to good children all over the world on the Christmas holiday.
The North American Aerospace Defense Command (NORAD) announced that it will follow Santa Claus on Christmas Eve, December 24. It has provided the service for 65 years.
There will, however, be some changes to NORAD’s usual Christmas Eve activities. With fewer volunteers, not every child will be able to reach NORAD’s call center to find out where Santa Claus is, as they have in years before.
Usually, 150-160 volunteers sit in a large office at Peterson Air Force Base in Colorado Springs. The volunteers spend two hours answering the telephone, talking to children who want to know when Santa Claus, or Father Christmas, will arrive in their town.
In the past, about 1,500 people have taken more than 130,000 phone calls from children, starting at 11:00 Universal Time on December 24. NORAD receives calls for 20 hours, about the time it takes Santa Claus to circle the earth.
This year, NORAD must follow safety restrictions forced by the COVID-19 pandemic. The number of volunteers has been cut to what NORAD expects will be fewer than 100 people.
“We understand this is a time-honored tradition, and we know undoubtedly there is going to be some disappointment,” said NORAD spokesman Preston Schlachter. “We’re trying to keep it safe for everyone involved,” he added.
So, some children may be able to get through to a member of the military or other volunteers when they call the NORAD Tracks Santa toll-free number, 1-877-Hi-NORAD. But others will get a recorded voice message stating Santa’s location.
Schlachter said NORAD will be limiting volunteers to people who already work there and their family members. But that could be expanded later. He said this year's volunteers will answer health questions and have their temperature taken when they arrive. Cleaners will wipe down surfaces throughout the day, and every two hours the room will be sanitized.
The military command has been taking Christmas Eve calls from children since 1955. That year, the commander on duty was Air Force Colonel Harry Shoup. He got a call from a child who was trying to speak to the Santa Claus at a local store, but had the wrong telephone number. Shoup quickly explained that he was Santa Claus, and the tradition began.
Today, most early calls come from Japan and Europe, and as the day goes on the callers from the U.S. and Canada increase.
Besides the call center, there is a NORAD Tracks Santa website, noradsanta.org, as well as social media pages. Amazon Alexa, Onstar and a new mobile app will also provide Santa’s location. A social media team will operate from a separate large office at the base.
The tracking Santa apps will soon be available on Google Play and the Apple App Store.
I’m Susan Shand.
The Associated Press reported this story. Susan Shand adapted it for Learning English. Mario Ritter, Jr. was the editor.
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Words in This Story
rejoice– v. to feel or show that you are very happy
pandemic– n.the fast spread of an infectious disease over a very large area or the whole world
disappointment– n. a feeling of unhappiness or sadness because something did not happen as expected
location– n. a place or position
sanitize– v. to make something free from dirt or infection
app– n.(computer) short for a computer application(2020/11/30 06:56)
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