Technicians test the deployment of one of the three massive solar arrays that will power NASA's Juno spacecraft.

In this photo taken on Feb. 2, 2011, each solar array is independently deployed at a Lockheed Martin Space Systems facility in Denver, Colo. This critical test simulates flight-like conditions, with the spacecraft's own electronics providing the command to deploy the array.

When Juno arrives at Jupiter in 2016, it will be farther from the sun than any previous solar powered mission. The choice of solar power for Juno necessitates very large solar arrays with dimensions of 2.65 meters wide by 8.9 meters long (about 9 feet wide by 29 feet long). Once in orbit at the giant planet, the three arrays will provide about 450 watts of electricity for Juno.

Juno aims to understand the origin and evolution of Jupiter.

NASA's Jet Propulsion Laboratory, Pasadena, Calif., manages the Juno mission for the principal investigator, Scott Bolton, of Southwest Research Institute at San Antonio, Texas. Lockheed Martin Space Systems, Denver, is building the spacecraft. The Italian Space Agency in Rome is contributing an infrared spectrometer instrument and a portion of the radio science experiment. JPL is a division of the California Institute of Technology in Pasadena.

For more information about Juno, visit http://www.nasa.gov/juno.