For years, astronomers and physicists have calculated the age of our universe by measuring the time elapsed since the Big Bang and by studying the oldest stars based on the redshift of light coming ...
About 150 hours of observing time on the 1,000-ft radio telescope at the Arecibo Observatory in Puerto Rico over the course of the last several years have been devoted to determining whether the most ...
Some numbers don’t change. These values are deeply connected to the very fabric of the Universe and our human existence. Until they aren’t, of course. Then we change them—for good reason. Scientists ...
The kilogram finally has a precise meaning despite defying a rigorous definition for over a century. Delegates of the General Conference on Weights and Measures unanimously voted Nov. 16 in favor of a ...
The kilogram — anywhere in the world, for any purpose — is based on the exact weight of a golf-ball-sized chunk of platinum and iridium stored under three glass bell jars in a vault in an ornate ...
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