Test Target

A test target is a common feature on interplanetary landing craft such as the Viking Lander and Mars Exploration Rovers.

The target is usually a visible marker or plate on the exterior of the vehicle within sight of the lander's imaging system (usually a CCD camera). The target possesses samples of primary colors and a grey scale. The camera uses this much like a photographer would use a chip chart on Earth; the color samples allow the camera to compensate for white balance and contrast. The target provides a visual reference as well, so that the initial orientation of the camera can be fixed.

On the Mars Exploration Rover, the target was designed with a pillar elevated above the main surface, so that it could be used as a sundial.


Famous quotes containing the words test and/or target:

    The test of a given phrase would be: Is it worthy to be immortal? To “make a beeline” for something. That’s worthy of being immortal and is immortal in English idiom. “I guess I’ll split” is not going to be immortal and is excludable, therefore excluded.
    Robert Fitzgerald (1910–1985)

    But this we know, the obstacle that checked
    And tripped the body, shot the spirit on
    Further than target ever showed or shone.
    Robert Frost (1874–1963)