Scientists discover most accurate clocks in the universe
Pulsars, or stars that pulse due to rapid spinning, may be the best way to keep time in space.
Tue, Jul 13, 2010 at 02:21 PM
An artist's conception of a pulsar planet. (Photo: NASA)
Time in space has always been an elusive issue for scientists who have long struggled to find a constant standard. But a new discovery may help us understand time as never before. Space.com reports that scientists are now using pulsars — rapidly spinning stars that pulse over time — to tell the universe’s time. This is due to a recent revelation about how pulsars function and rotate.
A pulsar is a rotating neutron star that emits a beam of electromagnetic radiation. When this radiation is pointed towards the Earth, we can see it much as we see the light from a lighthouse. Discovered in 1967 by Jocelyn Bell Burnell, pulsars occur in space when a star collapses, smashing the protons and electrons together into neutrons. They are so dense that one teaspoon of neutron star on Earth would weigh 1 billion tons.
It seems that these super heavy lighthouses of the universe are also predictable and steady in their actions. Their pulsing sweep of light is almost impeccably timed — almost. Until recently, scientists have been unable to account for a slight variation in the rate. But a new discovery shows that pulsars are slowly but surely slowing down and at two different rates. Further, they switch back and forth between the two rates. Now scientists must adjust the clocks to account for the difference. The end result? Constant time in space.
Why is constant time in the universe important? Andrew Lyne of the University of Manchester in England lead the recent pulsar study. As he told Space.com, "Mankind's best clocks all need corrections, perhaps for the effects of changing temperature, atmospheric pressure, humidity or local magnetic field. Here, we have found a potential means of correcting an astrophysical clock."
Further, experts hope that this new clock can help solve at least one space mystery. Albert Einstein suggested that gravitational waves — ripples in time-space caused by the merging of two black holes — exist in space. Scientists have never been able to find them, but this improved method of reading time may be the key to their discovery. If one of Einstein’s gravitational waves were to pass through a pulsar, it is possible scientists might be able to detect it.
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