Expected jitter performance has been verified on the integrated spacecraft using CSA's sensitive instrumented test stand. Results indicate that the small amount of jitter reaching the instrument will have negligible affect on image quality. In the end, the isolation system provides tremendous risk reduction for the spacecraft by drastically increasing the spacecraft margins.

The CMG Advantage
CMGs are high-speed motors and flywheels attached to gimbals, which quickly move the spinning wheels to different orientations. The mechanical advantage of CMGs is a rapid transfer of momentum between the CMG array and the spacecraft using only a modest amount of power. The CMG array nominally contains zero momentum, with large amounts of momentum in each individual CMG pointed in the opposite direction to the other CMGs in the array, ready to transfer it at a moment's notice.

The CMGs aboard WorldView-1 and WorldView-2 reduce slew time from over 60 seconds to only nine seconds to cover 300 kilometers. This means WorldView-2 will be able to rapidly swing a massive two-ton spacecraft, with a huge onboard camera, precisely from one target to another, allowing extensive imaging of many targets, as well as stereo imaging, in a single orbital pass. With a mission life of 7.25 years, and operating at an altitude of 770 kilometers, the WorldView-2 system is expected to bring unsurpassed agility, capacity, accuracy and spectral diversity to commercial Earth imaging.

Spacecraft Compatibility
Both WorldView satellites use the Ball Commercial Platform (BCP) 5000 spacecraft, a flight-proven, fixed-price system that offers increased resolution and rapid retargeting, as well as accommodates future optical, scientific and Synthetic Aperture Radar remote sensing payloads. The BCP 5000's power, stability, agility, data storage and data transmission capabilities combine to deliver comprehensive Earth remote sensing information.
 

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