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Gridley Herald - Gridley, CA
  • Looking Up: Perseids meteor shower - the highlight of summer

  • Meteors can be seen any night of the year, and there are a great many known showers.
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  • It's a highlight of the year among night sky gazers. Marking the height of summer year after year is the Perseids meteor shower, one of the strongest of displays. This year is highly favored, with only a crescent moon in the pre-dawn sky.
    Meteors can be seen any night of the year, and there are a great many known showers. They are generally named for the constellation from which they appear to radiate in the sky. They appear suddenly, any place in the sky. You can also see them at any hour of the night, although by far the most Who isn't startled by a meteor? Traditionally known as shooting stars, we should know that they aren't stars at all. They are bits of rock traveling through the solar system, caught by the Earth's gravity. They shine as they fall through the upper atmosphere, not by burning but by pressure against the air, causing the meteoric rock to heat up and glow.
    This also creates a shining trail of gases and melted meteoric particles. The meteor remains visible for only a matter of seconds. Fainter meteors appear like a quickly moving star. Bright ones often have a bright glowing head with a dim gray trail leading behind. A few rare, bright meteors leave a trail that lingers for several seconds after the head fades out. This will quickly become distorted in the high winds of the upper atmosphere.
    Unusually bright meteors are known as fireballs.
    Most meteors are around 60 to 100 miles up when you see them. If the rock is large enough, a piece will make it to the ground; we then call it a meteorite.
    Most meteoroids travel great loops around the sun, amassed together and spread around its orbit. Those that intersect the Earth's orbit rain down as "showers" when our planet comes by once a year. These meteor streams are left over from comets that have disintegrated. Other stray meteors may be bits of asteroid circling the sun.
    The Perseids meteor shower peaks on the night of Aug. 11, but a good display may be seen for several nights before and after. Under excellent conditions, you may see around 50 an hour. That means having a clear, dark and wide-open sky, and observing well after midnight.
    They seem to radiate from an area in the constellation Perseus (under the W-shaped constellation Cassoipeia), which is just rising in the northeast around midnight.
    Meteor showers are best after midnight because the morning side of Earth is on the forward side as the planet moves along in its orbit. Before midnight, we are on the trailing side; we rotate along with the Earth under our feet, and move into the forward side, plowing into the path of incoming meteors.
    Dress warm (it can get surprisingly chilly in August). Try using a lawn chair and plan on being patient. You can see some before midnight as well, but not as many. While you wait you can always enjoy the stars and constellations. Binoculars and telescopes aren't needed! Hot chocolate and cookies help.
    Page 2 of 2 - Planet parade
    Meanwhile, don't miss the parade of planets in the evening dusk and morning dawn. Looking west-southwest after sunset, findthe bright star Spica (white), Mars (reddish) above it or to the right, and Saturn (yellowish) above Mars. The crescent moon passes by these on Aug. 21.
    Look in the east during morning twilight for brilliant Jupiter up high, and brilliant Venus to the lower left. Farther to the lower left is Mercury, harder to see in the glow. The crescent moon passes by Jupiter on Aug. 11-12.
    Let me know about any meteors that you see. Send notes to news@neagle.com. Please mention where you read this column.
    Last-quarter moon is Aug. 9.
    Keep looking up!
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