ISIR-AL

Time period

May 1999 through December 1999

Project description

The ISIR-Atmospheric Lidar (AL) is a Lidar system designed for use from the Space Shuttle cargo bay. The ISIR-AL system does not have its own laser transmitter, but uses the return signal from the transmitter on the accompanying Shuttle Laser Altimeter (SLA) system.  The ISIR-AL system consists of a telescope which is an exact copy of that used in SLA. The light collected by the telescope is focused into a set of optics that collimates the beam, splits the light into two channels, and then focuses these two channels into fiber optics. The telescope assembly is shown in the cut-away view to the right. The telescope tube is the orange ribbed structure and the primary mirror is shown in blue at the bottom of the tube. The two fiber optic cables can be seen at the top of the telesocpe near the window (shown in green but actually clear). The fiber optics are held to the telescope tube with the three vanes shown in yellow. The entire telescope tube is lowered into a standard GAS (Get Away Special) can used for transporting instruments in the Space Shuttle cargo bay and is shown as the blue cut-away cylinder. Once in orbit, the lid of the cannister is opened and the ISIR-AL instrument views the Earth. The two fiber optic cables are routed to a pair of detectors (not shown) that are mounted to the brown plate shown at the bottom.

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