Sometimes you can sit back and watch the sky falling stars. They say that when you see a shooting star, it is necessary to make a wish, and it will be granted.
But what we take for falling stars, is just small stones flying from outer space. Approaching the planet, the stone hits the air shell and so much heat that begins to Shine like a star. Soon the asterisk, before reaching the Earth, burned and extinguished. These space aliens are called meteors. If part of a meteor reaches the surface, it is called a meteorite. Very bright meteors are called meteors.
Per day in the Earth's atmosphere there are hundreds of millions of meteors. Their mass is measured in thousands of tons per day. But, in addition, for days on Earth gets about 100 tons of dust particles, too small to cause the appearance of visible meteors.
Some days, the meteors appear in the sky more often than usual. This phenomenon is called meteor shower (people say that is star rain), when there are tens of thousands of meteors per hour.
If we look at the sky the way of meteors, it would appear that they all depart from the same point. It is called the radiant flux. This visual illusion occurs because of a phenomenon perspectives (like we see when we look at the railroad and see that the horizon rails converge). Actually meteoric particles parallel trajectories.
Astronomers have identified several dozen meteor showers. Many of which occur annually, and last from several hours to several weeks. Usually meteor showers referred to by the name of the constellation in which lies their radiant: for example, the Perseids, with the radiant in the constellation Perseus, the Geminids with radiant in Gemini.
Meteor shower, the Perseids
Where is the "star rain"? Meteor showers occur when the Earth crosses the path of a swarm of particles, formed during the destruction of the comet. When the comet approaches the Sun, it heats its rays and loses the substance. For several centuries under the action of gravity planets, these particles form an elongated Roy along the comet's orbit. If the Earth crosses this stream, we observed each year Starfall.