Apparently the Earth has unexpectedly speeded up a bit. Since 1955 when the atomic clock was invented, and time therefore could be measured more precisely, it became clear that each year doesn't have exactly the same length. Thus, in 1972 an extra "leap second" was added to each year, in order to make things fit. Because, presumably, the earth is slowly rotating slower and slower. It is just that, in the last five years, the earth is no longer rotating as slow as it was then, so the leap seconds don't seem to be needed. In other words, the earth speeded up a little bit, contrary to expecation. I'm glad she has a mind of her own. [ Science | 2004-01-01 16:06 | | PermaLink ] More >
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