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You can think of NASA's Discovery program as a sort of outer-space American Idol: every few years the agency invites scientists to propose unmanned planetary missions. The projects have to address some sort of fundamental science question, and (this is the tough part) they have to be relatively cheap to pull off — say, half a billion dollars or so. Then the proposals go through a grueling competition before judges who aren't as nasty as Simon Cowell but who are every bit as tough. The one left standing at the end gets the equivalent of a recording contract: NASA supplies the funding and the launch vehicle, and away the winner goes — to orbit Mercury, as the Messenger spacecraft is doing right now; or to rendezvous with a couple of asteroids, as the Dawn mission will start doing this July; or to smash into a comet on purpose, a feat achieved by Deep Impact in 2005, a mission not to be confused with the movie of the same name. Now it's time for the next contenders. NASA has just announced that the first round of the latest Discovery competition is over, with three entries out of 28 moving on to the finals. They are, in increasing distance from Earth: the Geophysical Monitoring Station (GEMS) lander, which would use seismometers to study the interior of Mars; the Comet Hopper, which would do just that, leaping from place to place across the surface of Comet 46P/Wirtanen to see how different parts of the tumbling body react to heating by the sun; and the Titan Mare Explorer (TiME), which would plop into a sea of liquid hydrocarbons on Saturn's moon Titan — the first oceangoing vessel ever to set sail on another world. If you had to come up with a theme that ties all three missions together, it would be "origins." The Titan explorer, for example, will be studying a place that — in a crude way, at least — resembles the early planet Earth at a time when life arose here. Titan, with a thick atmosphere and a bizarro-world form of weather featuring toxic winds and hydrocarbon rain, is home to a mix of complex chemistry, complete with organic molecules. The oceans provide a medium in which the molecules can move around and interact with each other. It's even conceivable, though clearly a long shot, that some form of microscopic life already exists on this frigid moon. The Mars lander, by contrast, would visit a place where the seas — plain water in this case — vanished long ago. But the mission of GEMS goes far deeper than that. By analyzing Marsquakes on the Red Planet, GEMS will try to get a handle on what the interior of Mars is like. Scientists don't currently know whether the planet's core is liquid, like Earth's, or solid, or some mushy consistency in between. It all depends on how efficiently Mars has cooled since it formed 4.5 billion years ago, and that depends in turn on the planet's internal structure. "That's the mission," says Bruce Banerdt, of NASA's Jet Propulsion Laboratory, the lead scientist for GEMS. "We want to understand how Mars was built." Along with sensitive seismographic equipment, GEMS will drill down about 20 ft. (6 m) with a thermometer-equipped probe, trying to figure out how quickly the temperature rises with depth. "That will let us extrapolate all the way down to the center," Banerdt says, "which will tell us how fast Mars is cooling."

BEIJING, Feb. 4 (Xinhua) -- The Chinese government Friday initiated a relief and assistance program for eight drought-ravaged provinces, said a statement on the website of Ministry of Agriculture.The government had implemented a grade II emergency response, meaning a 24-hour alert, daily damage reports, and the dispatching of experts and relief materials, said the statement.The ministry had sent teams to help with relief work in the provinces of Hebei, Shanxi, Jangsu, Anhui, Shandong, Henan, Shaanxi and Gansu, said the statement.The four-month drought had affected 35.1 percent of wheat crops, -- 96.11 million mu (6.4 million hectares) -- accounting for 21.7 percent of total farmland in the provinces, it said.The wheat growing area in the eight provinces accounted for more than 80 percent of the country's total, said the statement.The provinces have received little rainfall since October last year, it said.

BEIJING, Jan. 25 (Xinhua) -- The central parity rate of yuan, the Chinese currency, Tuesday gained 2 points to 6.5881 against the U.S. dollar, according to the China Foreign Exchange Trading System.China's central bank announced in June 2010 it would further reform the exchange rate formation mechanism to improve its flexibility.On China's foreign exchange spot market, the yuan can rise or fall 0.5 percent from the central parity rate each trading day.The central parity rate of the RMB against the U.S. dollar is based on a weighted average of prices before the opening of the market each business day.

BEIJING, Feb. 9 (Xinhua) -- China's Ministry of Agriculture on Wednesday urged more measures be taken to minimize the impact of a drought due to the possibility that the winter drought may continue into spring.The country's winter wheat producing regions have suffered severe drought since October last year, and the possibility of spring drought is surfacing, Minister of Agriculture Han Changfu said in a statement posted on the ministry's website.Spring drought following the winter one will be a significant threat to summer grain production, he said.As of Wednesday, the drought had affected about 115.95 million mu (7.73 million hectares) of winter wheat in the country's eight key producing provinces, which account for 42.4 percent of the total winter wheat growing areas in the regions, the statement said.China's main wheat growing regions include the provinces of Shandong, Henan, Hubei, Anhui, Shanxi, Shaanxi, Gansu and Jiangsu.Han urged agricultural authorities to be "fully aware of the extreme significance" of a summer harvest this year and strengthen their efforts to assure a successful harvest.Summer grain and oil production is crucial to easing inflation pressures and stabilizing grain output for the entire year, he said. "To have a summer harvest, the current pressing job is to protect winter wheat from drought," he said.There are currently positive factors for a summer harvest, including an adequacy of water for spring irrigation, according to Han.He ordered local agricultural officials to work to stabilize spring planting areas and ensure that the areas for grain planting will be equal to that of last year.Local agricultural officials were also asked to strengthen supervision over market supplies of agricultural materials to keep prices stable.Also on Wednesday, the State Council, or the nation's cabinet, pledged to boost grain production by raising minimum purchase prices of grain, subsidizing the purchase of anti-drought technologies and adding funding for farm irrigation.

BEIJING, May 19 (Xinhuanet) -- Google on Wednesday began fixing a security hole in some 97 percent of Android phones that could let hackers snatch important credentials at public WiFi hotspots.The fix, which addresses a hole allowing hackers to access the contacts, calendars and photos on an Android phone connected to an open WiFi network, will take a few days to cover every phone, a Google spokesman said.Unlike a traditional software update, the problem exists on Google's servers, so Android users won't need to manually take action.The newest versions of Android, including the new wave of tablets running its Honeycomb software, are not affected by the bug, according to the researchers at Germany's University of Ulm who initially reported the issue.The vulnerability could also cause devices synchronizing with Google Picasa web albums to transmit sensitive data through unencrypted channels, the researchers added.The Google spokesman said the company's security team is still investigating those claims.