NASA Delays Shuttle Launching After Finding Hydrogen Leak and Crack - New York Times

KENNEDY SPACE CENTER, Fla. — The shuttle Discovery, already delayed three times by technical problems and bad weather, was grounded again Friday, this time by a potentially dangerous gaseous hydrogen leak in a vent line attached to the ship’s external tank.

The Discovery was initially scheduled to make its 39th and final flight last Monday, bearing fresh supplies and an intelligent robot for the International Space Station. But complications delayed the flight from Monday to Friday, when the hydrogen leak led NASA to conclude that the shuttle would not be ready to launch before its flight window closed this Monday.

Almost at the same time that NASA managers were deciding to delay another attempt until Nov. 30, the opening of the next available launching window, engineers spotted a 7-inch-long crack in protective foam insulation on the side of the giant tank.

The crack, on the side of the tank facing the Discovery, represented a possible source of debris that could have posed a threat to the shuttle’s fragile heat shield during the climb out of the dense lower atmosphere.

Officials said the crack would have been spotted during normal prelaunching inspections and most likely would have prompted a delay even if the hydrogen leak had not developed. In the end, senior NASA managers decided to take the time needed to make sure the problems were well understood and repaired before making another attempt.

“We will come back in late November and give it another shot,” said Michael Leinbach, the launching director. “We’re going to fly when we’re ready, and clearly we were not ready to fly today.”

The Discovery’s six-member crew — Cmdr. Steven W. Lindsey; Col. Eric A. Boe of the Air Force, the shuttle pilot; Col. Benjamin A. Drew Jr., also of the Air Force; Col. Timothy L. Kopra of the Army; Nicole P. Stott; and Dr. Michael R. Barratt, a physician-astronaut — flew back to Houston after the launching scrub was announced.

The Discovery is attempting an 11-day mission to deliver critical supplies and equipment to the International Space Station. It will be loaded with a new cargo module, more than 6,000 pounds of supplies and equipment and a spare set of cooling system radiators that will be stored outside the lab complex.

Because of temperature issues related to the space station’s orbit, NASA will have only about one week, from Nov. 30 through Dec. 5 or 6, to get the Discovery off the ground this year. Otherwise, the flight could be delayed until late February, throwing a wrench into NASA’s plans for carrying out a final three missions and retiring the shuttle fleet by next summer.

“Discovery’s not going out easy,” Mr. Leinbach joked earlier in the week. “She’s giving us a little bit of trouble. But that’s fine — she’ll fly perfectly when she does.”

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3 share Nobel Prize in chemistry for finding new ways to bond carbon atoms - Washington Post

An American and two Japanese scientists won the Nobel Prize in chemistry Wednesday for finding new ways to bond carbon atoms together, methods now widely used to make medicines and in agriculture and electronics.

Richard F. Heck, Ei-ichi Negishi and Akira Suzuki were honored for their development in the 1960s and '70s of one of the most sophisticated tools available to chemists today, called palladium-catalyzed cross coupling.

It lets chemists join carbon atoms together, a key step in the process of building complex molecules. Their methods are used worldwide in commercial production of pharmaceuticals, including potential cancer drugs, and molecules used in the electronics industry, the Royal Swedish Academy of Sciences said.

The method invented by Heck is used in herbicide production, the academy said.

Heck, 79, a professor emeritus at the University of Delaware, now lives in the Philippines. Negishi, 75, is a chemistry professor at Purdue University in West Lafayette, Ind., and Suzuki, 80, is a retired professor from Hokkaido University in Sapporo, Japan.

The techniques developed by the three scientists have been used to artificially produce cancer-killing substances first found in marine sponges, the academy said in its citation. It is not yet clear whether the artificial substances will turn out to be useful drugs.

The techniques are also being used to create new antibiotics that work on resistant bacteria and a number of commercially available drugs, including the anti-inflammatory naproxen, prize committee member Claes Gustafsson said.

"There have been calculations that no less than 25 percent of all chemical reactions in the pharmaceutical industry are actually based on these methods," he said.

Palladium-catalyzed cross coupling is also used by the electronics industry in the coating of electronic circuits and as a tool to develop thinner computer screens in the future, said prize committee member Jan Erling Backvall.

Heck started experimenting with using palladium as a catalyst while working for an American chemical company in Delaware in the 1960s. In 1977, Negishi developed a variant of the method, and two years later, Suzuki developed another.

Heck was the only American among the Nobel science winners this year. There had been at least two U.S. scientists among the medicine, physics and chemistry laureates since 1991, when there was none.

- Associated Press

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