Near Earth Objects Essay Example | Topics and Well Written Essays - 1000 words

Near Earth Objects - Essay Example However, some asteroids which orbit near the sun can intersect with the earth’s path, and the results could vary from no-effect to catastrophic. Asteroids are floating masses of rocks which can also have a mix of iron and nickel. These irregularly-shaped chunks which can range from boulder-size to that of our very own moon are, thanks to Jupiter’s massive size and pull of gravity, held near the huge planet and Mars. There are different classes or types of NEAs depending on their aphelion distance, perihelion distance, and semi-major axes, namely, Aten, Apollo, and Amor. To show their differences, here is a table from the Near Earth Object Programpage of the NASA portal (â€Å"Neo Groups,† NASA Portal): Chunks of ice, dust, and rocky rubble that travel though space are called comets. Comets go much farther than asteroids do, reaching as far as the orbit of Neptune or even way beyond to a cloud surrounding the outer solar system known as the Oort cloud. Comet size usually ranges from half a mile to six miles across. A comet’s travel around the sun can take from a few years to thousands. Comets sometimes get â€Å"dislodged from their orbits by gravity and flung toward the sun, gases vaporizing off the surface create the familiar ‘tail’† (Wyckoff, â€Å"Asteroids and Comets†) that people see. Although this trail of gas and debris is considered a thing of beauty to behold, we must take note that this is due to a dislodgement in the comet’s orbit and things could certainly turn very ugly once size, speed, and direction come into play. One good example of that is the comet Shoemaker-Levy 9. In July of 1994, this catastrophic comet collided with Jupiter—the first collision of two heavenly bodies in the solar system to be observed. The comet was broken into fragments and left huge marks on the planet. Fragment A, for example, â€Å"struck