File:Precision is Important in Moving the Webb's FGS (7727991920).jpg

When it comes to testing, precision is the key. In this photo, technicians in the giant clean room at NASA Goddard Space Flight Center in Greenbelt, Md. have just installed a lift sling to move the Fine Guidance Sensor/Near InfraRed Imager and Slitless Spectrograph (FGS/NIRISS) instrument.

The sling is the red object that is above and attached to the FGS. The FGS/NIRISS must be aligned perfectly so the instrument's weight is evenly distributed during a lift. Just a small difference in weight distribution could damage the "struts" (the two silver arms underneath the gold-colored FGS/NIRISS). The technician looking at the FGS is visually checking to see if the sling is square before the lift starts.

The Canadian Space Agency's contribution to the Webb mission, the FGS/NIRISS arrived at NASA Goddard on July 30, 2012. The FGS/NIRISS is the second instrument to arrive at NASA Goddard that will fly aboard the James Webb Space Telescope. The Fine Guidance Sensor will enable the telescope to accurately and precisely point at the correct, intended objects for it to observe.

For more information about the James Webb Space Telescope, visit: <a href="http://www.jwst.nasa.gov" rel="nofollow">www.jwst.nasa.gov</a>

Photo Credit: NASA/Chris Gunn

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