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Meteor Showers (A Condensed Listing)

There are dozens of meteor showers each and every year. Listed here are several of the annual showers, including viewing dates, Peak dates and the Zenithal Hourly Rate (ZHR). In a nutshell, the ZHR is the number of meteors per hour you could expect to see in optimal conditions: new moon and no clouds, away from city light pollution. These numbers are not however a guarantee. Some showers with a high ZHR can be disappointing for several years and then put on a spectacular show. Showers with a low ZHR will occasionally astound viewers with a massive display. The thing is, you just never know!

Photo Credit: Nigel Cooke

Quadrantids (QUA)
Jan. 1 - Jan. 5, Peak Jan. 3, ZHR - 120
The first meteor shower of the year, the Quadrantids is one of the best and also one of the shortest. The peak of this winter shower lasts only a few hours. Although this shower typically produces in excess of 100 meteors per hour at its peak, the cold and overcast conditions of January keep most watchers indoors. Recently NASA teams took extreme measures to get decent views of this quick shower: they took an airplane to the Arctic Circle and rose above the clouds for viewing.

Alpha Centaurids (ACE)
Jan. 28 - Feb. 21, Peak Feb. 8, ZHR - 6
Although a very weak shower in terms of meteors per hour, with its over three-week duration, chances are good that on a cold, clear night a brilliant "shooting star" will be seen.

Gamma Normids (GNO)
Feb. 22 - Mar. 22, Peak Mar. 13, ZHR - 8
This rather small shower comes from the rather small constellation Norma, located in the Southern Hemisphere. Situated between Scorpius and Centaurus, the constellation's name is Latin for normal. The Latin word refers to a right angle, quite appropriate considering the constellation resembles a carpenter's square.

Lyrids (LYR)
Apr. 16 - Apr. 25, Peak Apr. 22, ZHR - 15
The Lyrids are a fairly steady shower, averaging 10 meteors per hour. On occasion the Earth will pass through a thicker part of the dust trail of Comet Thatcher. What then follows is a meteor storm. During one such storm in 1982, viewers were treated to 90 Lyrids per hour. The best time for viewing this shower is during the darkest hours before dawn.

Eta Aquariids (ETA)
Apr. 19 - May 28, Peak May 5, ZHR - 60
The outbound particles of Halley's comet produce this rather lengthy shower, best seen in the Southern Hemisphere. This shower is noted for producing a very high percentage of meteors with visible trains, almost 50%, making the Eta Aquariids the strongest annual shower in the Southern Hemisphere. For a week around the peak date, over 30 meteors may be seen per hour.

Alpha Capricornids (CAP)
Jul. 3 - Aug. 15, Peak Jul. 30, ZHR - 4
A low rate shower best seen from the Southern Hemisphere.What makes this shower stand out is its bright, vividly colored fireballs that frequently fragment while in flight. This is an ideal shower for the patient photographer.

Perseids (PER)
Jul. 17 - Aug. 24, Peak Aug. 12, ZHR - 60
The Perseids are undoubtedly the most well-known in the Northern Hemisphere, largely due to the time of year in which this shower occurs. The ZHR has fluctuated wildly in the last twenty years, most likely due to the reappearance of Swift-Tuttle, the parent comet of the Perseids. In 1991 and 1992, the ZHR was reported to be over 400 per hour.

Orionids (ORI)
Oct. 2 - Nov. 7, Peak Oct. 21, ZHR - 20
Produced by the inbound particles from Halley's comet, this shower has remained fairly consistent in the past twenty years. The Orionids can be seen equally well from both hemispheres; however, viewers in the Southern Hemisphere generally see twice the number of meteors per hour as those in the north.

Draconids (GIA)
Oct. 6 - Oct. 10, Peak Oct. 8, ZHR - Varied
Parented by the periodic comet Giacobini-Zinner, the hourly rate is impossible to predict. In both 1933 and 1946, this shower's ZHR was in the thousands. In 1998, viewers in Japan and eastern Asia were treated to over 500 meteors per hour, as reported by the Nippon Meteor Society.

Leonids (LEO)
Nov. 14 - Nov. 21, Peak Nov. 17, ZHR - Varied
This shower is quite noted for bright, different colored meteors that leave long-lasting trains. Composed of particles from the Comet Temple-Tuttle, this shower produces brilliant displays when the comet is close to Earth, often becoming meteor storms. In one of the most magnificent storms in recorded history, over one hundred thousand meteors fell per hour east of the Rocky Mountains in North America in 1833.

Geminids (GEM)
Dec. 7 - Dec. 17, Peak Dec. 13, ZHR - 120
Relatively new in space time, the Geminids were first noted only 150 years ago. The parent object, asteroid 3200 Phaethon, was discovered in 1983 by the Infrared Astronomical Satellite. High hourly rates and yearly reliability make this a shower of choice among seasoned meteor watchers. It is thought that this shower is producing more meteors each year and is definitely one to keep an eye on.

Two artists' portrayals of the Leonid Meteor Showers in 1866 and 1833, respectively

Author Resource: Written by Starr Hendon


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