Orionids
From Wikipedia, the free encyclopedia
Meteor showers, such as the one named after the constellation Orion, are the fallen debris of a passing comet. Meteor showers are times when you can see many meteors or shooting stars in one night. There are several meteor showers that occur each year, such as the Leonids in November, the Geminids in December, or the Perseids in August. Most meteor showers can be seen for several nights. Usually, there is one night (possibly two) when you can see the most meteors. This night is called the peak of the meteor shower. The peak of the Orionid shower is around October 21st. The Orionid Meteor Showers are caused by the well known Halley’s Comet, named after the famous astronomer Edmund Halley. Although Halley’s Comet comes around once every 75-76 years, the meteor shower occurs every year in October. It has been 22 years (1986) since Halley's Comet last passed through the inner solar system. So if you happen to live to 2061 then you will be able to see Halley’s Comet with the naked eye, soaring through our atmosphere at high speeds around the sun’s gravitational force. When Halley’s Comet gets as near as it can to the Sun, the comet starts to heat up. Its ices melt and the dust is trapped in the ice as it escapes into space. The dust spreads out over the comet's orbit. When Earth passes through the debris stream of Halley’s Comet, the meteoroids hit the atmosphere at nearly 148,000mph (miles per hour). When they hit Earth's atmosphere, they burn up and glow; the glowing trails that they leave behind for a quick second or two are what we see as meteors. We typically spot 10-15 meteors an hour before dawn. A typical debris particle is about the same size as a grain of sand, but it is much less dense, weighing only 0.01 gram. During a meteor shower, it looks like the entire batch of meteors shoot outward from one place in the sky. That point in the sky is called the radiant of the meteor shower. Each shower has a different radiant. The radiant for the Orionid meteor showers is in the constellation Orion. This is why this shower is named the Orionids. The radiant of the Orionids is located near the left shoulder of Orion the Hunter, centered within a triangle consisting of Sirius (the brightest star in the sky) and the giant planets Jupiter and Saturn (These are in the south-eastern sky before dawn, as viewed from mid-northern latitudes).
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 Orionid |
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 Two Orionids and Milky Way |
 Multi-colored Orionid |
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 The brightest meteor, a fireball, leaves a smokey persistent trail drifting in high-altitude winds, which is seen at the right-hand side of the image. |
