Although this year's Perseid meteor shower won't peak until Saturday night, the best viewing may well be just before tomorrow at dawn, since the waxing moon will wash out the show somewhat by this weekend. Perseus rises near midnight this time of year. It lies right along the Milky Way in the northeast sky, near the distinctive "W" shape of Cassiopeia, to the left of the Great Square of Pegasus. Perseus is between Cassiopeia and the brilliant star Capella in the constellation Auriga. The constellation contains the variable star Algol, considered the Medusa head that Perseus holds, which is not a single star but a triple-star system that waxes and wanes every three days depending on whether one of the system's dimmer or brighter stars is in front eclipsing the others.
The Perseid cloud stretches along the 130-year orbit of the comet Swift-Tuttle and consists of a stream of particles ejected each time the comet approaches the sun. The August meteor shower, which results from the Earth's annual passage through the relatively static stream, has been observed for about 2000 years. Most of the meteors we see this week will have been ejected about a thousand years ago, but there is a new filament that was ejected only in 1862, which generates a higher volume of visible falling stars than the older portion of the stream.
For years I've wanted to try a trick I read about: you set out a large flat pan the first time it rains after a meteor shower, then carefully let the pan dry out. Supposedly the remaining dust will react to a magnet, because it contains traces of iron from meteor dust in the upper atmosphere. I've never made it work. It would be hard to try this year, as we're beginning to wonder if it will ever rain again.
That reminds me of a quotation of Mark Twain that my husband cited to me yesterday: During a thunderstorm, someone asked whether he thought the rain would stop. "It always has before," he replied.
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