October 7, 2013
Eyes On The Sky! – Annual Draconid Meteor Shower Starts Tomorrow
[ Watch the Video: Catch The Draconid Meteor Shower Tonight ]
Brett Smith for redOrbit.com - Your Universe Online
Astronomers are hoping for a good show Tuesday night in the form of the Draconid meteor shower. Because the shower is expected to start just after dusk, experts say the annual show is an ideal one for the casual astronomer.
The shooting stars are a byproduct of the Giacobini-Zinner comet, which orbits the sun every 6.6 years. With each pass, the comet leaves behind a thin filament of dust that Earth encounters every year in early October.
“Most years, we pass through gaps between filaments, maybe just grazing one or two as we go by,” Bill Cooke of NASA’s Meteoroid Environment Office noted ahead of the 2011 shower. “Occasionally, though, we hit one nearly head on–and the fireworks begin.”
Cooke’s office appears to be closed as of posting time due to the federal government shutdown.
The meteor shower gets its name Draconid because the meteors appear to come from the northern constellation Draco the Dragon, which can be seen just above the Little Dipper in the night sky. Experts say this year should provide especially good sky watching because the moon is waxing and won't significantly interfere with the display.
Although they are conveniently scheduled, the meteor shower is highly unpredictable and can be frustratingly lackluster some years. The erratic nature of the shower has been traced back to a close encounter Giacobini-Zinner had with Jupiter in the late 19th century. The encounter with Jupiter’s gravitational pull shifted the comet’s orbit and created some uncertainty as to where it will shed its debris. Various models place the filaments in different spots, resulting in meteor rate estimates ranging from dozens to hundreds per hour.
The comet was discovered on December 20, 1900 by the French astronomer Michel Giacobini. Another sighting in 1913 by Ernst Zinner resulted in the name Giacobini-Zinner. The relationship between the comet and its meteors was so studied and discussed in the early 20th century that the meteor shower is sometimes referred to by the name Giacobinids.
Two of the Draconid meteor shower’s most memorable display occurred in 1933 and 1946, with thousands of meteors falling per hour. In 2011, observers around the world saw a fantastic show despite a bright full moon.
For optimum viewing, experts recommend finding a dark area away from a major population center with as much open sky as possible. After locating an ideal spot, simply recline in a comfortable chair and look upward – preferably just as the sun goes down. Experts recommend allowing 20 minutes for the eyes to adjust to the darkness.
As the sun sets, the moon and two planets, Venus and Saturn, should be visible in the southwesterly section of the sky just above the horizon. The moon and planets will essentially serve as a warm-up act to the Draconid meteor show. A waxing crescent moon can be seen between the planets Venus and Saturn on Monday night. On Tuesday October 8, the moon will be near Venus and the star Antares, right in the middle of the constellation Scorpius.