The Leonid Meteor Shower is a prolific meteor shower associated with the Tempel-Tuttle coment. The Leonids are named from the location of their radiant based in the constellation Leo as they appear to radiate from that point in the sky. As the Earth moves through the meteoroid stream, frozen gases, solid particles, and meteoroids (particles ejected from the passage of the comet) evaporate under the head of the sun a comet.
The Leonids are bright meteors or fireballs, are fast moving and come close to or cross the path of the Earth at the impact of 72 km/s, can cause meteor showers or storms, and deposit 12 or 13 tons of particles across the entire Earth. Leonids sometimes produce meteors or fireballs 9 mm across with a mass of 85 g, a force in the atmosphere similar to the kinetic energy of a car impacting a wall at 60 mph.
The Leonids tend to peak on November 17 but can occur in the days proceeding or following and are the most reliable "shooting star" sky shows annually. In 2010, the Leonids will be best viewed in areas with clear, dark skies in the predawn hours of Thursday, November 18, 2010.