A relatively rare event happens Monday, May 9, 2016. Essentially an eclipse of the Sun, this is one few people will notice.Every several years, the little planet Mercury passes between the Sun and the Earth, visible to those with special protection to safeguard their eyes at a telescope, as a tiny round dot silhouetted against the brilliant face of the Sun.Although it acts like an eclipse when the Moon covers the Sun, astronomers refer to this as a transit. Much more rare is when the [...]
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