Team Hollywood News Headline
All Science And Technology Articles News
Chase Credit Card
Supreme Court shuts out environmentalists
WASHINGTON, July 4 (UPI) -- The latest U.S. Supreme Court term was the worst one ever for environmentalis...
Genetically modified vines avoid virus
AACHEN, Germany, July 3 (UPI) -- Genetic engineering could make grapevines immune to a common virus that now r...
Old gene mutations may cause cancer today
BEERSHEBA, Israel, July 3 (UPI) -- Gene mutations that once helped humans evolve and survive could increase the ...
Fewer California sea otters reported
MONTEREY, Calif., July 3 (UPI) -- A decrease in California's endangered sea otter population likely means their...
No DNA link between Etruscans, Tuscans
FLORENCE, Italy, July 3 (UPI) -- Modern Tuscans show no genetic relationship to the Etruscans who occupied the...
Butterfly offers lessons in climate change
OXFORD, England, July 3 (UPI) -- The reintroduction of the Large Blue butterfly to Britain offers lessons in h...
ESA: Rubidium clocks operating as expected
PARIS, May 21 (UPI) --
The European Space Agency says Europe's first satellite-borne rubidium clocks have been in orbit for more than a year, operating mostly as expected. The ESA said the timekeeping of the clocks on the Galileo spacecraft will play an important role in determining the overall accuracy of the system, so evaluation of their performance is a crucial part of the Galileo in-orbit verification process. The orbit of GIOVE-A is precisely measured by a network of 10 ground-based laser ranging stations, to provide orbital data independent of the navigation data. The technique used to characterize clock performance is a statistical method with a precision so great that tiny orbit disturbances caused by the pressure of sunlight shining on the satellites is taken into account. Comparisons between the on-board clocks and identical units undergoing on-ground life testing show no unexpected aging or performance degradation is occurring due to the space environment, so they are expected to easily exceed their required 12-year operational lifetime. Galileo, when fully deployed during the early years of the next decade, will be the first civilian positioning system to offer global coverage.
Print article · Return to Website · Email This Article
© UPI, Headline News Powered by Bravenet.com
bravenet.com