Thursday, January 17, 2013

Shuttles, Turning Sedentary, Leave Pieces Behind for Science and Safety

As the agency gets its space shuttles ready to be shipped out to museums, it will not be sending them off lock, stock and barrel. The crews doing the prep work have been flooded with requests to squirrel away parts of the spacecraft for analysis. Valves, flight-control instruments, even the tires and windows — little is safe from the clutches of NASA engineers.

“I’ve got a list of hundreds of items that have to come off the ship,” said Stephanie S. Stilson, who is directing the preparation of the shuttle Discovery for delivery to the Smithsonian Institution next year in what NASA calls its “transition and retirement” program.

In April, NASA named the permanent old-age homes for its shuttles, which have been escorting astronauts to space for 30 years. The Endeavour, which completed its last mission early Wednesday with a pinpoint landing after 16 days in orbit, will bask in glory only briefly before it is groomed for delivery to the California Science Center in Los Angeles. The Atlantis, which will make its final flight next month, is destined to live at the visitors’ center here at the space center.

The Discovery made its last flight in March and now sits in a maintenance bay, enclosed by platforms that would normally be crawling with workers inspecting and maintaining its many systems — including the thousands of thermal tiles that cover its skin — to be ready for its next liftoff. These days, as the shuttle program winds down and the staff has been winnowed by layoffs, technicians work on the Discovery only when there are no more pressing tasks. And rather than sprucing it up for another trip to space, likely as not they are taking something out of it.

“We in engineering, we want to hold on to things that we could potentially use, or we want to study them, which is a smart thing to do,” Ms. Stilson said. The shuttles are the only spacecraft that have been launched into orbit multiple times — the Discovery is the most-traveled, with 39 missions — and a better understanding of how the materials and equipment have fared could help future aerospace designers.

Ms. Stilson spoke near one of the Discovery’s main landing gears, where the tires used on the last flight had been removed in favor of what NASA calls “roll-around tires” — basically a bunch of old spares. On a higher platform, workers were putting the finishing touches on replacement windows for the spacecraft, the originals having been taken out so engineers could study what effect the microdebris encountered in so many trips in space had on the glass.

While those who are to receive the shuttles say they understand the need for research, they are a little surprised by how much will be missing.

“We’re considered to be the nation’s official repository of our past,” said Valerie Neal, curator for contemporary human spaceflight at the Smithsonian, which will display the Discovery at the National Air and Space Museum’s annex near Dulles Airport. “Our point of view would be to receive an orbiter in as intact a state as possible.”

Ms. Neal said that when she first started discussing the fate of the shuttle with NASA several years ago, “I rather naïvely thought it would be intact.”

Some of the removal work is dictated by safety concerns. There are small explosive charges all around the shuttle, including one designed to blow a latch and deploy the front landing gear should the normal systems fail. Although the firing mechanism has been disabled, “We don’t want to take a chance that if it’s sitting in the Smithsonian it could somehow detonate,” Ms. Stilson said.

The thrusters near the shuttle’s nose and the podlike maneuvering engines in the rear both contain propellants that are highly toxic and corrosive, even in tiny amounts. So these components have been removed and sent to a special facility where workers in hazardous materials suits will “cut and gut” them, removing much of the insides before shipping them back. “We’ll reinstall them, and from the outside they’ll look exactly the same,” Ms. Stilson said.


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Wednesday, January 9, 2013

Ambitious Plan for China’s Water Crisis Spurs Concern

A chronic drought is ravaging farmland. The Gobi Desert is inching south. The Yellow River, the so-called birthplace of Chinese civilization, is so polluted it can no longer supply drinking water. The rapid growth of megacities — 22 million people in Beijing and 12 million in Tianjin alone — has drained underground aquifers that took millenniums to fill.

Not atypically, the Chinese government has a grand and expensive solution: Divert at least six trillion gallons of water each year hundreds of miles from the other great Chinese river, the Yangtze, to slake the thirst of the north China plain and its 440 million people.

The engineering feat, called the South-North Water Diversion Project, is China’s most ambitious attempt to subjugate nature. It would be like channeling water from the Mississippi River to meet the drinking needs of Boston, New York and Washington. Its $62 billion price tag is twice that of the Three Gorges Dam, which is the world’s largest hydroelectric project. And not unlike that project, which Chinese officials last month admitted had “urgent problems,” the water diversion scheme is increasingly mired in concerns about its cost, its environmental impact and the sacrifices poor people in the provinces are told to make for those in richer cities.

Three artificial channels from the Yangtze would transport precious water from the south, which itself is increasingly afflicted by droughts; the region is suffering its worst one in 50 years. The project’s human cost is staggering — along the middle route, which starts here in Hubei Province at a gigantic reservoir and snakes 800 miles to Beijing, about 350,000 villagers are being relocated to make way for the canal. Many are being resettled far from their homes and given low-grade farmland; in Hubei, thousands of people have been moved to the grounds of a former prison.

“Look at this dead yellow earth,” said Li Jiaying, 67, a hunched woman hobbling to her new concrete home clutching a sickle and a bundle of dry sticks for firewood. “Our old home wasn’t even being flooded for the project and we were asked to leave. No one wanted to leave.”

About 150,000 people had been resettled by this spring. Many more will follow. A recent front-page article in People’s Daily, the Communist Party’s mouthpiece, said the project “has entered a key period of construction.”

Some Chinese scientists say the diversion could destroy the ecology of the southern rivers, making them as useless as the Yellow River. The government has neglected to do proper impact studies, they say. There are precedents in the United States. Lakes in California were damaged and destroyed when the Owens River was diverted in the early 20th century to build Los Angeles.

Here, more than 14 million people in Hubei would be affected if the project damaged the Han River, the tributary of the Yangtze where the middle route starts, said Du Yun, a geographer at the Chinese Academy of Sciences in Wuhan, the provincial capital.

Officials in provinces south of Beijing and Tianjin have privately raised objections and are haggling over water pricing and compensation; midlevel officials in water-scarce Hebei Province are frustrated that four reservoirs in their region have sent more than 775 million cubic meters, or 205 billion gallons, of water to Beijing since September 2008 in an “emergency” supplement to the middle route.

Overseers of the eastern route, which is being built alongside an ancient waterway for barges called the Grand Canal, have found that the drinking water to be brought to Tianjin from the Yangtze is so polluted that 426 sewage treatment plants have to be built; water pollution control on the route takes up 44 percent of the $5 billion investment, according to Xinhua, the official news agency. The source water from the Han River on the middle route is cleaner. But the main channel will cross 205 rivers and streams in the industrial heartland of China before reaching Beijing.

“When water comes to Beijing, there’s the danger of the water not being safe to drink,” said Dai Qing, an environmental advocate who has written critically about the Three Gorges Dam.

Li Bibo, Jonathan Kaiman and Jimmy Wang contributed research from Beijing.


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