| Asteroids Earth grazers and objects Apollo |
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Please enter the asteroids beyond Jupiter's orbit, would not others to penetrate beyond the orbit of Mars, closer to the Sun? The first such cases was discovered August 13, 1898 by a German astronomer Gustav Witt. Detected the asteroid 433 and saw that the period of revolution was only 1.76 years, which is 44 days shorter than that of Mars. Therefore, its average distance from the Sun must be less than that of Mars. The new asteroid was called Eros. Anyway, if Eros and Earth are at the appropriate points of their orbits, the distance between them is only 23 million miles. This is a little more than half the minimum distance between Venus and Earth, and means that if we do not have our own Moon, Eros was, at the time of its discovery, our closest neighbor. There is a very large body. Judging by the changes in brightness, is shaped like a brick, and its average diameter is about five miles. Anyway, one thing is not negligible. If you collide with Earth, a disaster happen. In 1931, Eros approached a distant point only 26 million kilometers from Earth, and established a vast astronomical project to determine its exact parallax, so that the distances in the solar system could be determined more accurately than ever. The project was successful, and the results were not improved until the radar beams were reflected from Venus. An asteroid comes close to Earth than Venus, is called (with some exaggeration) grazier from Earth. Between 1898 and 1932, only discovered three more Earth grazers, and each of them approached our planet unless Eros. However, this mark was broken on March 12, 1932, when a Belgian astronomer, Eugene Delporte, discovered the asteroid 1221, and saw that, although its orbit was a regular on the Eros, getting closer to 16 million miles Earth's orbit. He called the new asteroid Amor (the Latin equivalent of Eros). On 24 April 1932, exactly six weeks after the German astronomer Karl Reinmuth discovered an asteroid, which he called Apollo, because it was another grazier from Earth. It was an asteroid striking since, at perihelion, is only 95 million kilometers from the Sun is moving not only within the orbit of Mars, but also within the Earth, and even Venus . However, its eccentricity is so large that at aphelion is 353,000,000 miles from the sun, beyond what happens to Eros. The period of revolution of Apollo is, therefore, 18 days longer than that of Eros. On 15 May 1932, Apollo approached within 10,725,000 miles from Earth, less than 30 times the distance of the Moon. Apollo owns less than two miles wide, but large enough to be well come not as 'grazier'. Since then, anything that comes close to the Sun than Venus as it does, has been named Apollo object. In February 1936, Delporte, who had detected four years before Love, sighted another grazier Earth he called Adonis. Just a few days before its discovery, Adonis was now only 2,475,000 miles from Earth, or only a little over 6, 3 times the distance of the moon to us. What's more, the new grazier on earth has a perihelion of 65 million miles, and this distance is very close to the orbit of Mercury. Apollo was the second object discovered. In November 1937, Reinmuth (the discoverer of Apollo), sighted a third, which he called Hermes. Had passed 850. 000 kilometers from Earth, only slightly more than twice the distance of the moon. Reinmuth, with data available, calculated an orbit roughly according to which Hermes could pass just 313,000 kilometers from Earth (a distance less than what separates us from the Moon), as long as Hermes and Earth found in the appropriate points of its orbit. However, since then there has been again a Hermes. On 26 June 1949, Baade discovered the most unusual of Apollo objects. Its period of revolution was only 1, 12, and its orbital eccentricity was the largest known asteroids: 0.827. At its aphelion, is safe in the asteroid belt between Mars and Jupiter, but in its perihelion is close to 28,000,000 miles from the sun, closer than any planet, including Mercury. Baade called this asteroid Icarus, as the young man of Greek mythology, flying through the air with the wings his father Daedalus had designed was too near the sun, which melted wax is assuring the feathers of the wings on his back, and fell causing the death. Since 1949, other objects have been discovered Apollo, but none has come close to the sun like Icarus. However, some have orbital period of less than one year and at least one is closer, at every point in its orbit, the Sun than Earth. Some astronomers estimate there are in the Apollo space about 750 objects with diameters of one kilometer and more. It is believed that, over a million years, four have achieved respectable Apollo objects on Earth, three to Venus and Mercury one both as to Mars or the moon, and seven have had their orbits so that affected all have left the solar system. The number of Apollo objects, however, does not diminish with time, so it is likely to be added others from time to time because of gravitational perturbations of objects in the asteroid belt.
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