THURSDAY, OCTOBER 6 If you go outside and face south this evening at around 11 p.m., you'll be greeted by the alluring sight of a waxing gibbous Moon bracketed by Saturn and Jupiter. The two planets are nearly 44° apart, and the Moon is roughly in the middle - a couple of degrees closer to Saturn than to Jupiter. But the apparent distances between these worlds presents only a two-dimensional picture. To fully appreciate the scene before you, consider the extreme depth-of-field (to borrow a photographic term) involved. Sunlight reflecting off the lunar surface takes just a touch longer than 1 second (1.23 seconds, to be precise) to reach your eyes this evening. Even though Jupiter has just had its closest opposition in nearly six decades, it's obviously much more distant than the Moon.
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