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Home | Meteors
A meteor, sometimes called a "shooting star," can be the brightest object in the night sky, yet meteoroids are the smallest bodies in the solar system that can be observed by eye. Wandering through space, perhaps as debris left behind by a comet, meteoroids enter the earth's atmosphere, are heated by friction, and for a few seconds streak across the sky as a meteor with a glowing trail.
A brilliant meteor, called a fireball, may weigh many kilograms, but even a meteor weighing less than a gram can produce a beautiful trail. Some of these visitors from space are large enough to survive (at least partially) their trip through the atmosphere and impact the ground as meteorites. Fireballs are sometimes followed by trails of light that persist for up to 30 minutes; some, called bolides, explode with a loud thunderous sound.
How can a particle the size of a grain of sand produce such a spectacular sight? The answer is the speed at which the meteoroid enters the earth's atmosphere. Many meteoroids travel at 60-70 kilometers per second. As a comparison, the shuttle moves around the earth at about 8 kilometers per second.
During its trip through the atmosphere, meteoroids collide with air molecules, knocking away materials and stripping electrons from the meteor. When the stripped atoms recapture electrons, light is emitted. The color of the light depends on the temperature and the material being "excited."
On almost any night a few meteors an hour will be seen from any one place. However, periodically there are meteor showers, with hundreds of meteors emanating from the same apparent spot in the sky. These showers typically last from a few hours to several days. These showers are usually associated with comet paths, and are caused by debris expelled by the comet.
Each day as many as 4 billion meteors, most miniscule in size, fall to earth. Their masses total several tons, seemingly a large amount, but negligible compared to the earth's total mass of 6,600,000,000,000,000,000,000 tons.
|Quadrantids (QUA)||January 1||January 3||January 5||230 deg||49 deg||-|
|Cancrids (DCA)||January 1||January 17||January 24||130 deg||20 deg||More Info|
|Centaurids (ACE)||January 28||February 7||February 21||210 deg||-59 deg||More Info|
|Leonids (DLE)||February 15||February 24||March 9||168 deg||16 deg||-|
|Normids (GNO)||February 26||March 13||March 22||249 deg||-51 deg||More Info|
|Virginids (VIR)||January 26||March 24||April 15||195 deg||-4 deg||-|
|Lyrids (LYR)||April 16||April 22||April 25||271 deg||34 deg||-|
|Puppids (PPU)||April 15||April 24||April 28||110 deg||-45 deg||-|
|Aquarids (ETA)||April 19||May 5||May 28||338 deg||-1 deg||More Info|
|Sagittarids (SAG)||April 15||May 19||July 15||247 deg||-22 deg||-|
|June Bootids (JBO)||June 26||June 27||July 2||224 deg||48 deg||-|
|Pegasids (JPE)||July 7||July 9||July 13||340 deg||15 deg||More Info|
|July Phoenicids (PHE)||July 10||July 13||July 16||32 deg||-48 deg||More Info|
|Piscis Austrinids (PAU)||July 15||July 28||August 10||341 deg||-16 deg||More Info|
|South. Aquarids (SDA)||July 12||July 28||August 19||339 deg||-30 deg||More Info|
|Capricornids (CAP)||July 3||July 30||August 15||307 deg||-10 deg||More Info|
|South. Aquarids (SIA)||July 25||August 4||August 15||334 deg||-15 deg||More Info|
|North. Aquarids (NDA)||July 15||August 8||August 25||335 deg||-5 deg||More Info|
|Perseids (PER)||July 17||August 12||August 24||46 deg||58 deg||More Info|
|Cygnids (KCG)||August 3||August 17||August 25||286 deg||59 deg||-|
|North. Aquarids (NIA)||August 11||August 19||August 31||327 deg||-6 deg||-|
|Aurigids (AUR)||August 25||September 1||September 8||84 deg||42 deg||More Info|
|Aurigids (DAU)||September 5||September 9||October 10||60 deg||47 deg||More Info|
|Piscids (SPI)||September 1||September 19||September 30||5 deg||-1 deg||-|
|Draconids (GIA)||October 6||October 8||October 10||262 deg||54 deg||More Info|
|Epsilon Geminids (EGE)||October 14||October 18||October 27||102 deg||27 deg||-|
|Orionids (ORI)||October 2||October 21||November 7||95 deg||16 deg||-|
|Southern Taurids (STA)||October 1||November 5||November 25||52 deg||13 deg||More Info|
|Northern Taurids (NTA)||October 1||November 12||November 25||58 deg||22 deg||More Info|
|Leonids (LEO)||November 14||November 17||November 21||153 deg||22 deg||-|
|Monocerotids (AMO)||November 15||November 21||November 25||117 deg||1 deg||More Info|
|Orionids (XOR)||November 26||December 2||December 15||82 deg||23 deg||More Info|
|Dec Phoenicids (PHO)||November 28||December 6||December 9||18 deg||-53 deg||More Info|
|Puppid/Velids (PUP)||December 1||December 7||December 15||123 deg||-45 deg||More Info|
|Monocerotids (MON)||November 27||December 9||December 17||100 deg||8 deg||More Info|
|Hydrids (HYD)||December 3||December 12||December 15||127 deg||2 deg||More Info|
|Geminids (GEM)||December 7||December 14||December 17||112 deg||33 deg||-|
|Coma Berenicids (COM)||December 12||December 19||January 23||175 deg||25 deg||-|
|Ursids (URS)||December 17||December 22||December 26||217 deg||76 deg||More Info|
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