科技英语新闻:NASA's Juno spacecraft ready to start journey to Jupiter

LOS ANGELES, July 27 (Xinhua) -- The Juno spacecraft of the National Aeronautics and Space Administration (NASA) arrived at its launch pad at the Cape Canaveral Air Force Station in Florida on Wednesday, ready for a mission to Jupiter to study the solar system, the Jet Propulsion Laboratory (JPL) said.

The solar-powered, Jupiter-bound spacecraft was secured into place on top of its rocket at 10:42 a.m. EDT (7:42 a.m. PDT), said JPL in Pasadena, California.

Juno will arrive at Jupiter in July 2016 and orbit its poles 33 times to learn more about the gas giant's interior, atmosphere and aurora, according to JPL.

"We're about to start our journey to Jupiter to unlock the secrets of the early solar system," said Scott Bolton, the mission 's principal investigator from the Southwest Research Institute in San Antonio, Texas. "After eight years of development, the spacecraft is ready for its important mission."

Now that the Juno payload is atop the most powerful Atlas rocket ever made -- the United Launch Alliance Atlas V 551 -- a final flurry of checks and tests can begin and confirm that all is go for launch, according to JPL.

The final series of checks begins Wednesday with an on-pad functional test. The test is designed to confirm that the spacecraft is healthy after the fueling, encapsulation and transport operations.

"The on-pad functional test is the first of seven tests and reviews that Juno and its flight team will undergo during the spacecraft's last 10 days on Earth," said Jan Chodas, Juno's project manager at JPL. "There are a number of remaining pre- launch activities that we still need to focus on, but the team is really excited that the final days of preparation, which we've been anticipating for years, are finally here. We are ready to go. "

The launch period for Juno opens Aug. 5, 2011, and extends through Aug. 26. For an Aug. 5 liftoff, the launch window opens at 11:34 a.m. EDT (8:34 a.m. PDT) and remains open through 12:43 p.m. EDT (9:43 a.m. PDT), JPL said.

Managed by JPL, the Juno mission is part of the New Frontiers Program managed at NASA's Marshall Space Flight Center in Huntsville, Alaska.