At the Astrotech Space Operations facility in Titusville Fla. an engineer monitors the movement of the antenna.

At the Astrotech Space Operations facility in Titusville, Fla., an engineer monitors the movement, or gimbaling, of the high-gain antenna on the Solar Dynamics Observatory, or SDO. All of the spacecraft science instruments are being tested in their last major evaluation before launch. SDO is the first space weather research network mission in NASA's Living With a Star Program. The spacecraft's long-term measurements will give solar scientists in-depth information about changes in the sun's magnetic field and insight into how they affect Earth. In preparation for launch, engineers will perform a battery of comprehensive tests to ensure SDO can withstand the stresses and vibrations of the launch itself, as well as what it will encounter in the space environment after launch. Liftoff on an Atlas V rocket is scheduled for Dec. 4. Photo credit: NASA/Jack Pfaller