An overhead crane lowers the Cosmic Origins Spectrograph or COS into a protective enclosure on the Orbital Replacement Unit Carrier.

In the clean room of the Payload Hazardous Processing Facility at NASA's Kennedy Space Center, an overhead crane lowers the Cosmic Origins Spectrograph, or COS, into a protective enclosure on the Orbital Replacement Unit Carrier, part of the payload for the fifth and final Hubble servicing mission, STS-125. Other payloads include the Flight Support System, the Super Lightweight Interchangeable Carrier and the Multi-Use Lightweight Equipment, or MULE, carrier. COS will be the most sensitive ultraviolet spectrograph ever flown on Hubble and will probe the "cosmic web" - the large-scale structure of the universe whose form is determined by the gravity of dark matter and is traced by galaxies and intergalactic gas. The COS far-ultraviolet channel has a sensitivity 30 times greater than that of previous spectroscopic instruments for the detection of extremely low light levels. Launch of Atlantis on the STS-125 mission is targeted for Oct. 8. Photo credit: NASA/Kim Shiflett