A Comet is a body revolving around the sun. A comet is characterized by a long, luminous tail, but only in the segment of the comet's orbit when it passes closest to the sun. Composed mostly of water ice with rooted dust particles, comets originally formed in the cold outer planetary system while most of the rocky asteroids formed in the warmer inner solar system. A Meteor is a small solid body that enters a planet's atmosphere from outer space and raised to combusti

Some 65 million years ago dinosaurs and 75 percent of those species then on Earth seem to have been executed to extinction by the impact of a 10-kilometer-diameter (6-mile) NEO. The Tunguska event of 1908 in Siberia, warns the United States Air Force on small objects entering Earth's atmosphere, and particularly, the impact of some two dozen fragments of comet Shoemaker-Levy 9 with Jupiter in 1994 all underscore that dangerous impacts may occur today. The best estimate of the probability of a civilization-threatening collision in the next century is nearly one in 1,000.

Some common words found in the essay are:
NEO Earth-impact, Astronomical Units, Earth Objects, Air Force, Near-Earth Objects, Mars Jupiter, Earth Object, NEO Tunguska, near earth, Near Earth, sizes craters moon, craters moon planet, using ground-based telescopes, earth's atmosphere, planet mercury, search neos, solar system, entering earth's, air force, telescopes inferred sizes, craters moon, sun comet, ground-based telescopes inferred, nearly 1000,
Approximate Word count = 651
Approximate Pages = 3 (250 words per page double spaced)