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NASA Aims for First Manned SpaceX Mission in Q1 2020 – NDTV

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SpaceX’s Crew Dragon astronaut capsule will be ready for its first manned test flight into orbit in the first quarter of next year, provided that “everything goes according to plan” in upcoming tests, NASA chief Jim Bridenstine said on Thursday.

On a visit to the SpaceX headquarters, Bridenstine praised Elon Musk’s company for its “fail fast, then fix” approach to spacecraft design after a personal tour and briefing at the sprawling manufacturing plant – a display of unity amid a rare public spat between the two key space figures.

But he also emphasised NASA’s concern for astronaut safety, saying the timeline could slip.

“We are not going to take any undue risk,” Bridenstine said, standing beside Musk outside a clean room that contained a Crew Dragon capsule.

The National Aeronautics and Space Administration is paying commercial launch contractors SpaceX and Boeing $6.8 billion to build rocket-and-capsule systems to return astronauts to the International Space Station from US soil for the first time since America’s space shuttle program ended in 2011.

Bridenstine’s visit to SpaceX headquarters in the Los Angeles suburb of Hawthorne comes as SpaceX works to overcome key technical challenges on the Crew Dragon. SpaceX has so far never flown humans into orbit, only cargo.

Musk and Bridenstine said they were working together through concerns over re-entry parachutes and other technical challenges, some of which were first publicly detailed by Reuters.

“It’s a pretty arduous engineering job to get the parachutes right,” Musk said, declaring that Crew Dragon’s parachutes will have “twice the safety factor” than those used in the Apollo era.

“Testing will be complete and hardware at the Cape (Canaveral) by the end of December,” he added.

While Musk and Bridenstine provided few concrete details on their joint investigation into an explosion during a capsule ground test in April, Musk said incidents were inevitable during complex development processes and rigorous testing.

The visit follows a dispute over the last two weeks between Musk and the NASA chief, who bristled at Musk on Twitter for celebrating an unrelated milestone achieved on SpaceX’s deep-space Starship rocket while completion of the Crew Dragon project remained delayed.

Musk quickly shot back during a series of interviews, at one point citing a rival NASA moon rocket dubbed the Space Launch System that is years behind schedule and billions of dollars over budget. He also told CNN “most of the work” left to complete on Crew Dragon was related to “a long series of safety reviews” by NASA.

Both the Boeing and SpaceX capsules have been beset by delays and testing mishaps that have prevented either company from achieving goals for manned orbital missions in 2019.

RACE TO THE STATION

SpaceX successfully launched an unpiloted Crew Dragon in March to the International Space Station, a $100 billion orbital research laboratory that flies about 250 miles (400 km) above Earth.

Bridenstine told reporters on Thursday that a high-altitude abort test of a system designed to propel the capsule to safety in the event of an emergency on the way to orbit would happen in “short order,” though he did not provide a specific date.

Other testing includes 10 additional mid-air “drop tests” to test parachute resilience and performance, Bridenstine said.

NASA and SpaceX have had a strained relationship at times in recent years. SpaceX’s rise to become a dominant launch services provider for satellites over the last decade has been fuelled in part by NASA contracts and the agency’s transformative strategy to buy services from private companies rather than owning the technology itself.

The top executive for Boeing’s rival Starliner program, John Mulholland, told a conference on Wednesday that its own key test of an abort system that propels astronauts to safety during an emergency was slated for November 4, while its unpiloted orbital test flight was set for December 17.

Under that time frame, the first Starliner manned mission is all but certain to slip into 2020.

With no current means of flying astronauts into orbit from US soil, NASA has been paying Russia about $80 million per ticket for rides to the space station.

Bridenstine said NASA was “still buying seats” for ride-alongs aboard Russia’s Soyuz as an “insurance policy” against future delays in the crew capsule development.

Asked about his jab at Musk on Twitter, Bridenstine said he was “signalling” to SpaceX and all other NASA contractors that “we need more realism built in to our development time frames.”

© Thomson Reuters 2019

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Climate change triggers a chain reaction that threatens the heart of the Pacific – Prince George Citizen

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SHIRETOKO PENINSULA, Japan – Lined up along the side of their boat, the fishermen hauled a huge, heavy net up from swelling waves. At first, a few small jellyfish emerged, then a piece of plastic. Then net, and more net. Finally, all the way at the bottom: a small thrashing mass of silvery salmon.

It was just after dawn at the height of the autumn fishing season, but something was wrong.

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“When are the fish coming?” boat captain Teruhiko Miura asked himself.

The salmon catch is collapsing off Japan’s northern coast, plummeting by about 70 percent in the past 15 years. The disappearance of the fish coincides with another striking development: the loss of a unique blanket of sea ice that dips far below the Arctic to reach this shore.

The twin impacts – less ice, fewer salmon – are the products of rapid warming in the Sea of Okhotsk, wedged between Siberia and Japan. The area has warmed in some places by as much as 3 degrees Celsius (5.4 degrees Fahrenheit) since preindustrial times, making it one of the fastest-warming spots in the world, according to a Washington Post analysis of data from the nonprofit organization Berkeley Earth.

That increase far outstrips the global average and exceeds the limit policymakers set in Paris in 2015 when they aimed to keep Earth’s average temperature rise “well below” 2 degrees Celsius (3.6 degrees Fahrenheit).

The rising temperatures are starting to shut down the single most dynamic sea ice factory on Earth. The intensity of ice generation in the northwestern Sea of Okhotsk exceeds that of any single place in the Arctic Ocean or Antarctica, and the sea ice reaches a lower latitude than anywhere else on the planet. Its decline has a cascade of consequences well beyond Japan as climate dominoes begin to fall.

When sea ice forms here, it expels huge amounts of salt into the frigid water below the surface, creating some of the densest ocean water on Earth. That water then sinks and travels east, carrying oxygen, iron and other key nutrients out into the northern Pacific Ocean, where marine life depends on it.

As the ice retreats, that nutrient-rich current is weakening, endangering the biological health of the vast northern Pacific – one of the most startling, and least discussed, effects of climate change so far observed.

“We call the Sea of Okhotsk the heart of the North Pacific,” said Kay Ohshima, a polar oceanographer at the Institute of Low Temperature Science at Hokkaido University. “But the Sea of Okhotsk is significantly warming, three times faster than the global mean.

“That causes the power of the heart to weaken,” he said.

The cascade starts more than a thousand miles away in a uniquely frigid area of Siberia known as the “Cold Pole,” where the coldest temperature ever recorded in the Northern Hemisphere (-67.7 degrees Celsius or-89.9 degrees Fahrenheit) was measured in 1933.

The Cold Pole, too, is warming rapidly, by about 2.7 degrees Celsius (4.9 degrees Fahrenheit) since preindustrial times in the village of Oymyakon. That means the bitter north wind that blows down onto the Sea of Okhotsk is also warming.

The warmer wind inhibits the formation of sea ice. Across the Sea of Okhotsk, ice cover during the peak months of February and March has shrunk by nearly 30 percent in the past four decades, a vanishing of about 130,000 square miles of ice, an area larger than Arizona.

Masanori Ito, 67, recalls how, during his childhood, the ice would drift down from the sea’s northern reaches – a thick, white carpet descending on Abashiri, a city on the northeastern shore of Hokkaido, Japan’s northernmost prefecture.

“The drift ice used to arrive with a force, pushed and pushed from behind, from far out at sea,” said Ito, senior executive director at the Okhotsk Sightseeing Federation. It would pile up upon itself, forming “mountains over 10 meters high.”

Today, those mountains are long gone, and the coast of Hokkaido is hemmed in by ice for fewer than 25 days a year on average, said Arctic scientist Shuhei Takahashi, who runs the Okhotsk Sea Ice Museum of Hokkaido in Mombetsu.

A century ago, the coast typically had ice for more than 50 days each winter, Takahashi said. Based on current trends, he said, the drift ice could disappear entirely by the end of this century.

Meanwhile, the ice itself is also changing. Those who know it well say it sounds different, less intense, no longer an indomitable winter colossus.

“Years ago, our nose hair froze and stuck out. And our eyelashes would get moist and go all white,” said Shigeru Yamai, 66, captain of the icebreaker Garinko II. “When we walked on the ice, we heard squeaking sounds. The sound today is different. It hardly gets that severe anymore.”

– – –

For fisherman Nobuo Sugimura, 63, the changing climate is evident in his steadily diminishing catch. At home after a fishing trip on Miura’s vessel the Hokushin Maru, Sugimura brought out his logbooks and diaries, pulling records for his most recent catch in late September and for the same period seven years ago.

In 2012, Sugimura’s records show he and fellow crew members brought in between 21 and 52 metric tons of fish per day. This year, the catch one day was a meager six tons.

“We had a bad time 30 or 40 years ago, and this reminds me of that,” he said. “But that only lasted a year or two, not this long.”

In the nation that invented sushi, there is no region better known for its seafood than Hokkaido. And there is no fish more synonymous with Hokkaido, more central to its culture, than the salmon.

The relationship stretches back as long as humans have lived here. The indigenous Ainu people had 133 words for salmon and used its skin to make boots. The fish and its orange roe are critical ingredients in Hokkaido’s famous seafood sashimi rice bowl, savored by foodie tourists across this gourmet nation. The image of a bear clamping a salmon between its powerful jaws is an iconic symbol of Hokkaido, reproduced on T-shirts and in wood carvings on sale in almost every souvenir shop.

Though Hokkaido’s salmon hatcheries are working harder than ever, releasing a billion juvenile fish into the island’s rivers every spring, the number of returning chum salmon has declined sharply, from 68 million fish in 2003 to just 28 million in 2018. Nationwide, Japan’s annual chum salmon catch has also fallen from 258,000 metric tons in 2003, when a sharp decline began, to 80,000 last year, according to the North Pacific Anadromous Fish Commission.

Salmon are highly sensitive to changes in water temperature. As they swim into the Sea of Okhotsk at the start of their long migration across the Pacific, the warmer waters act as a force field, pushing them off their ancient track.

Compelled to travel faster and farther to reach cooler northern waters, the young salmon use up stores of energy when they can least afford it. If they delay their departure date, they won’t survive at all.

Masahide Kaeriyama, an emeritus professor in the Arctic Research Center at Hokkaido University, said Japanese salmon migrate up what he calls a “ladder” of suitable temperatures. For more than a decade, he has been predicting that climate change would cut Hokkaido’s salmon catch in half. Now, he says global warming is happening even faster than he expected.

“As the optimal temperature moves away from Hokkaido, the ladder of migration is being taken away,” he said.

Japan’s loss has been Russia’s gain. Waters near the Siberian coast – once too cold for salmon – are now in the optimum range for the fish. Even as Japan’s catch began to decline in 2003, Russia’s chum salmon quadrupled to a record high of nearly 144,000 metric tons in 2015. The same phenomenon is happening around the world, as warmer waters cause key species to seek cooler habitats closer to the poles. The lobster population off the Northeast coast in the United States is seeing a similar disruption.

If the Hokkaido salmon survive the first leg of their journey, they move into the Bering Sea, and then on to the Gulf of Alaska for their second winter. By the age of 4 or 5, they return to Japan, to the very same river where they hatched.

The smaller number of returning fish is keenly felt on Hokkaido’s Shiretoko Peninsula, home to the largest concentration of brown bears in the world. Each fall, as the salmon amass offshore, the bears are waiting, splashing in the streams at the mouth of every river. Here, the iconic image of a bear catching a salmon comes to life.

Salmon nourish the bears, and the bears’ leftovers discarded in the forest nourish birds, insects and plants, creating “one of the richest integrated ecosystems in the world,” according to UNESCO, the educational, scientific and cultural agency of the United Nations.

UNESCO made Shiretoko National Park a World Heritage Site in 2005. But as the drift ice recedes and the salmon catch shrinks, UNESCO worries that the park’s unique ecosystem will be irrevocably damaged.

“Japanese people see salmon as a source of food,” Kaeriyama said. “But salmon is, in fact, the very foundation of the ecosystem where we live.”

– – –

 

The link between sea ice and prosperity is not lost on the towns and cities of northern Hokkaido and the Shiretoko Peninsula, where the ice drives a vital tourism industry.

In the spring, as the ice melts and sunlight hits the water, the sea blooms with phytoplankton, the anchor of marine life and the base of the ocean’s food web.

That makes the Sea of Okhotsk a spectacularly bountiful stretch of water, home to whales and dolphins, sea lions and seals, scallop and crabs, and hundreds of species of fish. Its shores provide homes to many migratory and sea birds, from the largest owl in the world – the endangered Blakiston’s fish owl – to the heavy Steller’s sea eagle.

In Abashiri alone, about 110,000 people, nearly half of them foreigners, took sightseeing cruises last year across the vast expanse of sea ice. On the eastern side of the peninsula, tourist boats set out from the town of Rausu every winter to gaze at eagles perched on the ice and seals bobbing through it, and in the spring, summer and fall to watch humpback, sperm and killer whales splash through the waves.

Meanwhile, key nutrients, especially iron, flow into the Sea of Okhotsk from Russia’s Amur River. Undersea currents carry those nutrients into the North Pacific, forming an intermediate layer of water roughly 600 to 2,600 feet below the surface. Eventually, the water rises back up, bringing the iron that is vital for phytoplankton with it.

The Okhotsk sea ice decline jeopardizes that giant convection current. Ohshima, his fellow scientists from Hokkaido University and other institutions in Japan have documented a marked warming in the North Pacific’s intermediate layer, much more rapid than the general warming of the ocean – a sign that less cold, dense water is being formed in the Sea of Okhotsk.

Scientists have also documented growing zones in the North Pacific, at depths of about 1,300 and 2,300 feet, where ocean oxygen levels are in fast decline.

In other words, the “heart of the Pacific” is indeed weakening. The scientists don’t know all of the consequences yet, but they’re worried because of the irreplaceable contribution of the Sea of Okhotsk to a much larger region.

– – –

Back on Hokkaido, the falling salmon catch is triggering cascading economic impacts.

Last year, salmon processors paid high prices for dwindling supplies of Japanese chum salmon, only to find that consumers weren’t prepared to pay more. Japanese salmon was soon displaced by cheaper imports from places such as Norway, Chile, Russia and Alaska.

Tetsuya Shinya, head of the Abashiri Fisheries Cooperative, said he is reluctantly considering something once unthinkable: raising salmon on fish farms.

“It’s still not the right time to do it,” he said. “Even so, I feel we are getting into a pretty tough time.”

Wild salmon tend to be hardier and more resistant to changing temperatures than salmon reared in the more-controlled environment of a hatchery. One solution is a campaign to reduce Hokkaido’s dependence on salmon hatcheries by encouraging more wild salmon to return to the island’s rivers.

Scientists and volunteers are clearing rivers along the Shiretoko Peninsula, where anything from silt to concrete dams can prevent wild salmon from returning to spawn.

Among the volunteers is Yuto Sugimura, 32, the son of the fisherman whose records document the salmon’s startling decline.

Yuto said he never used to think much about climate change beyond what he saw on the news. But as he dove into the sea in September to set salmon nets, he didn’t need any records to tell him the temperature is rising.

“I’ve been going under the water for 15 years, but these days it feels quite lukewarm,” he said.

“Until you feel it on your skin or experience it in reality, you don’t talk about it,” Yuto said of climate change.

“Today, with the changes in the water, I am beginning to feel it on my skin, and I am beginning to think about it.”

– – –

The Washington Post’s Akiko Kashiwagi contributed to this report.

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Human-induced climate change dates back much further than we think: study – Folio – University of Alberta

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Human-induced climate change has origins far earlier than commonly assumed, according to a study published in the journal Science.

Archeological evidence collected around the world suggests human activity began warming the global climate about 5,000 years ago, according to U of A anthropologist Jack Ives, one of many scientists who contributed data to the study.

The authors found that “existing global reconstructions underestimatethe impact of early human land use onEarth’s current ecology,” since most studies of climate change focus on the recent past.

“While there has been an exponential increase in human impacts on climate in the last two centuries, that impact has a long tail running back at least 10,000 years, particularly with the advent of agriculture,” said Ives.

“We have been affecting the global environment for some time as a species,” he said, “and while known by archeologists, these findings have not received the attention they deserve.”

Major events in human history, such as the rise of extensive agriculture in the Fertile Crescent in the Middle East, rice agriculture in China and maize agriculture in parts of North, Central and South America “were beginning to impact methane and other greenhouse gases,” said Ives.

Ives said scientists use a model called the Milankovitch Cycle to predict climate change over thousands of years, based on changes in the Earth’s rotation, axial tilt and precession.

However, the accuracy of that model breaks down about 5,000 years ago, suggesting human intervention. 

“Things were becoming noticeably warmer, and couldn’t be explained by that Milankovitch patterning,” he said.

Crowdsourcing data

In the largest crowdsourcing study of its kind, published last August, 255 archeologists contributed data from more than 700 regional questionnaires describing hunting and gathering, pastoralist and agricultural land use at 10 time intervals—beginning 10,000 years ago and extending to the 19th century—across all continents except Antarctica.

The authors conceded that the regional information was not uniformly strong, and “differs greatly from one region to another.”

“Hot spots” of intensive study were concentrated in Europe, Southwest Asia, and portions of the Americas, and “cold spots” receiving much less attention were concentrated in Southeast Asia and Central and West Africa.

According to the available data, human activity, including burning and clearing of land for farming, began to significantly alter global patterns of biodiversity, ecosystem functioning and climate around 5,000 years ago.

By 6,000 years ago, 42 per cent of human-occupied land “had at least minimal extensive agriculture,” the study found. Evidence of climate warming is also consistent with the appearance of domestic animals between 4,000 and 8,000 years ago.

However, the researchers also found that, even before the domestication of plants and animals, “widespread evidence of hunter-gatherer land use indicates ecological conditions across most of the terrestrial biosphere were influenced extensively by human activities, including the use of fire to enhance success in hunting and foraging.”

“And in the Amazon Basin and other forested regions, (there was) a prominent form of horticulture that involved slashing and burning portions of the forest to allow for crop planting,” added Ives, who has been researching prairie archeology for the past dozen years as executive director of the U of A’s Institute of Prairie Archaeology.

Harnessing fire

He said there is strong evidence that First Nations people in North America, like Indigenous people in many regions, had “a systematic understanding of fire and its power,” engaging in purposeful controlled burning of forests and grasslands.

“Some communities undertook strategic burning to keep trail systems and portages clear, to open up campsites and also at times to purposely change the character of a forest. 

“The burning of climax boreal forest communities, for example, releases nutrients back to the soil, opens up the canopy and generates a new succession of animals and plants. Blackfoot and other Plains peoples could influence prairie forage through systematic uses of fire.”

Ives said there are signs the Blackfoot in southern Alberta burned land surrounding Head-Smashed-In Buffalo Jump to “clean it up” and eradicate the unbearable stench from the kill. The site was used for thousands of years, beginning about 6,000 years ago, to kill bison by driving herds off of a cliff.

“Shortly after the burn, people discovered there was a new flush of grass that was extremely attractive to feed bison,” said Ives.

He said there are lessons to be learned today from the earliest First Nations practice of controlled burning.

“Many of these incredibly destructive fires we’re seeing, such as in California, British Columbia and the northern Prairie provinces, can be attributed not just to climate change or global warming, but to the buildup of fuel because we have been suppressing fires for so long.”

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Researchers Highlight Progress and Challenges of Phloem Research – Lab Manager Magazine

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Phloem as a long-distance transport system and a habitat for prokaryotic pathogens and piercing-sucking insects.Credit: JIANG Yanjuan

Numerous insects and pathogens extract nutrients from phloem tissue buried deep inside plants. These phloem-feeding insects and pathogens cause tremendous economic losses worldwide and represent some of the most difficult pests to understand due to their specialized feeding strategies. The resulting infestations and diseases are also among the most costly and difficult to manage. However, for historic and technical reasons, our knowledge of phloem-insect/pathogen interactions has been fragmentary.

Now, a new study by researchers from the Xishuangbanna Tropical Botanical Garden (XTBG) and their collaborators brings this knowledge together. In a survey of the relevant scientific literature, the scientists highlight significant advances in the understanding of phloem interactions with insects and prokaryotic pathogens as well as make recommendations for future research. The report was published in the latest issue of PNAS on November 12.

The researchers point out that several studies have focused on identifying the secretomes of phloem-limited insects and pathogens over the past decade. Progress has been made in understanding how some effector proteins of phloem-associated insects facilitate the feeding behavior and performance of insects in plants. However, research to understand how they influence plant and insect physiology is still at an early stage.

Related Article: Researchers Find Chemicals that Treat Citrus Greening in the Lab

The researchers propose that interactions with phloem-feeding insects and pathogens should be considered when studying phloem, since it contains a fascinating collection of unique and interactive cell types.

Unlike phloem-feeding insects, prokaryotes cannot actively enter the phloem; therefore, all known phloem-associated prokaryotes are passively delivered into the phloem by phloem-feeding insects.

Innovative culturing approaches are also required for future research, in order to remove one of the most formidable barriers to the study of phloem-pathogen interactions.

“Most importantly, identifying host genes that underlie plant interactions with phloem-feeding insects and pathogens would be an attractive target for improving host resistance via introgression of naturally occurring variants or genome editing,” said Dr. Jiang Yanjuan, first author of the study.

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