July 28, 2011

NASA Readies Juno For Trip To Jupiter

NASA, looking forward to launching a Jupiter-bound mission next week, sent the Juno spacecraft to its final destination at the Cape Canaveral Air Force Station in Florida as the agency makes final preparations for the launch.

The solar-powered spacecraft was secured in place atop the United Launch Alliance Atlas V 55 rocket at 10:42 a.m. EDT on Wednesday.

The "most powerful Atlas rocket ever made" is sitting on the launch pad at the base while technicians carry out "a final flurry of checks and tests" before the first launch opportunity arises on August 5.

"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 NASA's Jet Propulsion Laboratory (JPL) in Pasadena, California. "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."

Juno is scheduled to spend one year orbiting inside Jupiter's radiation belts, far closer than any spacecraft has gone before, to learn how much water the giant planet holds, what triggers its massive magnetic fields and whether a solid core lies beneath the dense atmosphere. Juno will first need to travel 5 years through space before it reaches its destination sometime in July 2016.

"Jupiter holds a lot of key secrets about how we formed," lead scientist Scott Bolton, with the Southwest Research Institute in San Antonio, Texas, told Reuters.

"We're about to start our journey to Jupiter to unlock the secrets of the early solar system. After eight years of development, the spacecraft is ready for its important mission," he added.

Scientists believe Jupiter was the first planet to form after the birth of the Sun, though only speculation exists over how that occurred.

Any water content found on Jupiter would be directly tied to where -- and how -- the planet formed. Some evidence points to a planet that grew colder nether-regions of the solar system and then migrated inward. Other models show Jupiter formed at or near its present location by accumulating ancient icy snowballs.

However, as it grew, Jupiter ended up with a mass more than twice all its sister planets combined, giving it the gravitational muscle to hang on to all of its original building materials.

"That's why it's very interesting to us if we want to go back in time and understand where we came from and how the planets were made," Bolton told Reuters reporter Irene Klotz, adding that Juno will help scientists do that.

Only one other space probe got closer to Jupiter than Juno will get when it reaches the hot giant. A NASA probe released by Galileo was able to relay data for 58 seconds before succumbing to the planet's crushing pressure and intense heat.

Juno's electronics are protected in a vault of titanium, but it too will falter in the harsh Jovian environment after about a year. Juno's last job will be to dive into the planet's atmosphere to avoid any chance of contaminating Jupiter's potentially life-bearing moons.

"Three solar panels extend outward from Juno's hexagonal body, giving the overall spacecraft a span of more than 66 feet. The solar panels will remain in sunlight continuously from launch through end of mission, except for a few minutes during the Earth flyby. Before launch, the solar panels will be folded into four-hinged segments so that the spacecraft can fit into the launch vehicle," as explained by NASA.

The panels will power an array of kit which includes a six-wavelength microwave radiometer, plasma and energetic particle detectors, and ultraviolet and infrared imager/spectrometers. Juno is also carrying a color camera, promising Earthlings "the first detailed glimpse of Jupiter's poles," the agency said.

Juno is scheduled for a launch on August 5. However, NASA has a window that leads up to August 26 before it will no longer have favorable alignment to make the launch.

Juno was built by Lockheed Martin Astronautics of Denver, Colorado. The mission, the second in NASA's lower-cost, quick-turnaround New Frontiers planetary expeditions, will cost $1.1 billion.

JPL manages the Juno mission for principal investigator Scott Bolton. The Juno mission is part of the New Frontiers Program managed at NASA's Marshall Space Flight Center in Huntsville, Alabama. JPL is a division of the California Institute of Technology in Pasadena.


Image Caption: NASA's Juno spacecraft passes in front of Jupiter in this artist's depiction. The Juno mission is the first of NASA's three planetary missions launching this year, making 2011 one of the busiest ever in planetary exploration. Image credit: NASA/JPL-Caltech


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