Comets, meteors, and asteroids: their origin, properties, and geology

Comets are small celestial bodies, consisting mainly of form and gases that look at in an elongated elliptical or nearly parabolical mountain chain around the sun. When a comet is far from the sun, it consists of a soften solid body or conglomerate of bodies called the nucleus, made up of frozen gases with excite off the groundicles of heavier substances interspersed through discover. This is a a few(prenominal) miles in diameter. As it approaches the sun, a luminous cloud of dust and gases called the syncope envelops the nucleus. The comas luminosity is caused by the molecules absorbing and reflecting the radiation of the sun. As the comet approaches the sun, the solar worm drives particles and gases from the nucleus and coma to form a tail which can extend as much as 160 million km in length. The solar wind always makes the tail stream out in the counsellor opposite the sun; i.e., it follows the head as the comet approaches the sun and precedes it as the comet pas ses perihelion (its closest point to the sun) and moves away. Modern theories suggest that comets were organise during the organization of the solar system and are permanent members of it. principalgazer J. H. Oort has theorized that a spherical shell or cloud of to a great extent than 100 billion long-period comets surrounds the solar system at a distance of 75,000-150,000 AUs.

While the comets move very slowly in this huge storage cloud, a passing star whitethorn change their orbits enough to force some of them into the home(a) part of the solar system. (Seeds, 410) Astronomer G. P. Kuiper, noniced that Oor ts cloud of comets did not adequately peak ! for the short-period comets (those wit solar orbits less than two hundred years), proposed the existence of a disk-shaped region of minor planets outside the orbit of Neptune as... If you want to get a full essay, order it on our website: BestEssayCheap.com

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