IT'S NOT just those with delicate skin that need a bit of protection from the sun.
Northrop Gunman has successfully completed a preliminary design review of its sunshield membrane management subsystem, which will protect Nasa's James Webb Space Telescope (JWST) from high temperatures by blocking harsh solar light.
 "The sunshield is designed to block solar light and keep the observatory operating at cryogenic temperatures. The [shield] will help enable the Webb Telescope's infrared sensors to see distant galaxies, early stars and planetary systems, and help astronomers better understand dark matter," Northrop spokesperson Sally Koris told The News. "It's a five-layer sunshield that consists of extremely thin membranes and a supporting structure composed of spreader bars and a large composite shell - the size of a tennis court. The JWST sunshield will block the sun with a giant beach-umbrella-like sunshield the size of a tennis court. If you could imagine, this would be like an SPF of 1.2 million."
According to Koris, the management subsystem consists of covers and constraint devices used to protect and manage the membranes while stowed during launch, as well as features used to control the membranes during the deployment process.
As The News previously reported, Northrop recently tested a sophisticated cryocooler used to reduce thermal noise in space-borne sensors. The device comprises a 3-stage pulse tube cooler that deploys high-pressure helium gas to maintain temperatures ranging from 4.4K (-451.75 F) to 50mK.
"Cryocoolers are an enabling technology for future space exploration missions, like IXO [the International X-ray Observatory], which will enable scientists to study the high-energy  universe to discover more black holes, the formation and evolution of galaxies, and life cycle of matter and energy," explained Mark Folkman, director of sensors and phenomenology for Northrop's aerospace sector. "Cooling sensors to this level reduces thermal noise in the detectors and associated electronics, allowing the sensors to operate with more sensitivity and efficiency."
According to Folkman, Northrop supplied the cryocooler for Japan's Greenhouse Gases Observing Satellite (GOSAT), which was recently launched to study the negative affects of global warming. Similar, high temperature cryocoolers were manufactured for the Geostationary Operational Environmental Satellite-R Series (GOES-R).
A number of future science missions are likely to benefit from cryocooler technology advancements, including the Single Aperture Far-Infrared Observatory, (SAFIR) and the Terrestrial Planet Finder (TPF).
"We've progressed beyond the 6K cooling point engineered for the Mid-Infrared Instrument (MIRI) on the James Webb Space Telescope," said Jeff Raab, manager of cryocooler systems for Northrop's aerospace sector. "We expect further work to extend cooling capabilities down to 2K, using this flight-proven technology that can enable mission life exceeding 10 years."
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