Why do shooting stars have glowing tails?
(Lansing State Journal, August 5, 1992)
Shooting stars are not stars at all, rather they are quickly moving bits of rock and debris that have entered the Earth’s atmosphere called meteors. Along with stars and planets, space contains many pieces of rock and dust called meteoroids. As Earth moves around the sun, some of these pieces are pulled toward Earth by gravity. When one of these piece enters Earth’s atmosphere it is moving so fast that it actually knocks electrons out of atoms in the atmosphere.
This leaves a trail of free electrons which are negatively and positively charged electrons called ions. Around one second after the shooting star has passes, the free negatively charged electrons are attracted to the nearby positively charged atoms and combine with them.
When this happens, energy is released by the electron in the form of light. The light emitted by these electrons form the glowing tail people see behind shooting stars.
The rock, ice and dust that make up the bulk of the meteoroid are heated by the friction between itself and the air. The material that was the meteoroid is burned up and the light given off by this burning forms the head of the meteor.
August provids a good opportunity to see shooting stars; Earth passes through a bend of meteoroids that orbits the sun much ike the Earth does. As Earth passes through the band, many of the pieces that make up the band will enter Earth’s atmosphere. This yearly event is called the Perseid meteor shower.