GeoWorld

NEWSLINK NASA's Deep Space Atomic Clock to Improve Navigation Technology When people think of space technologies, many think of high-tech solar panels, complex and powerful propulsion systems or sophisticated, electronic guidance systems. Another critical piece of spaceflight technology, however, is an ultra-stable, highly accurate device for timing—essential to NASA's success on deep-space exploration missions. NASA is preparing to fly a Deep Space Atomic Clock (DSAC) demonstration that will revolutionize the way it conducts deep-space navigation by enabling a spacecraft to calculate its own timing and navigation data in real time. This one-way navigation technology would improve upon the current two-way system in which information is sent to Earth, requiring a ground team to calculate timing and navigation, and then transmitted back to the spacecraft. A laboratory representation of the Deep Space Atomic Clock (top) shows a quarter alongside the unit for size comparison. A CAD drawing (bottom) describes the clock's linear ion trap—the "heart" of the clock's physics package. DigitalGlobe Turns to Crowdsourcing for Oklahoma Tornados NASA/JPL 6 G E O W O R L D / A U G U S T 2 O 1 3 "Adopting DSAC on future NASA missions will increase navigation and radio science data quantity by two to three times, improve data quality by up to 10 times, and reduce mission costs by shifting toward a more flexible and extensible one-way radio navigation architecture," said Todd Ely, principal investigator of the DSAC Technology Demonstration at NASA's Jet Propulsion Laboratory in Pasadena, Calif. The project is part of NASA's Technology Demonstration Missions program, managed by the Marshall Space Flight Center in Huntsville, Ala., for NASA's Office of the Chief Technologist in Washington, D.C. The one-way deep-space navigation enabled by DSAC uses the existing network more efficiently than the current two-way system, expanding the network's capacity without adding new antennas or their associated costs. This is important, because future human exploration of deep space will demand more tracking from the deep-space network than currently delivered. The clock is a miniature mercury-ion atomic device the DSAC team will fly as a payload on an Earth orbiter in a one-year experiment to validate its operability in space and its usefulness for one-way navigation. Ground-based atomic clocks have long been the cornerstone of most space-vehicle navigation, because they provide root data necessary for precise positioning. DSAC will deliver the same stability and accuracy for spacecraft exploring the solar system. In much the same way that modern GPS uses one-way signals to enable terrestrial navigation services, the DSAC will provide a similar capability in deep-space navigation. Following deadly tornadoes that ripped through Oklahoma in spring 2013, imagery provider DigitalGlobe turned to a "crowdsourcing" approach to enhance information provided to disaster responders. The company also applied crowdsourcing techniques to find burned buildings in the wake of Colorado's devastating Black Forest wildfire. In Oklahoma, the approach involved launching the company's recently acquired Tomnod Crowdsourcing System and alerting—via e-mail, Facebook and Twitter—a "crowd" of public users who could provide basic analysis and supplemental information

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