Comets are Solar system bodies having the form of vague objects, usually with pale clot kernel in the center and tail. They are among the most beautiful celestial bodies. hazy Bright shell surrounding a core of hazy, long tail, extending sometimes to half the sky, fast motion among the stars – all this makes comet different from other heavenly bodies. The comet can be observed when a small ice body, called the nucleus of the comet is approaching the Sun at a distance that is less than 4-5.e. warmed by the sun, and it begins to stand out gases and dust that are visible as a result of their illumination by the Sun.
Gases and dust released from the nucleus, creating around him a hazy shell – atmosphere of the comet, components along with the core of the head of the comet. The atmosphere of a comet continuously dissipates in interplanetary space: under the action of radiation pressure and interaction with the solar wind gases and dust are carried away in the direction from the Sun forming the comet’s tail.
Most of the comets in the middle of the head there is a bright star-like “core”, representing the illumination of the Central, most dense zone of true gases around the comet’s nucleus. Continue reading
Halley’s comet is a bright, unique comet with a period of return to the Sun of about 75-76 years, which is visible even to the naked eye. The official astronomical name of this celestial body – 1P/Halley. For the comet Halley for the first time managed to determine the elliptical orbit and set the frequency of motion in the Solar system than did the Englishman Edmond Halley (1656-1742) the astronomer Royal, physicist, geophysicist, meteorologist, mathematician and demographer, in whose honor was named the comet.
In ancient times, people observed the appearance of Halley’s comet, but did not suspect that I see the same cosmic body. The first surviving written evidence about the emergence of a “heavenly sign” dates back to the year 249 BC, and since then the approaching comet was observed at least thirty times. The last observation of the comet Halley was possible in 1986, and the next is expected in the summer of 2061. I must admit that if an event of this magnitude is regarded as an auspicious time for space exploration, once the appearance of comets were regarded by the people as a “terrible sign” of the coming change, wars, government coups. For the most part, it’s because of “strong world” of those times. It is known that Genghis Khan saw a comet, regarded it as a personal message and a call for conquest of neighboring lands. The same happened in ancient China, and even at the dawn of our era in Europe. Continue reading
Comets fascinate the human mind since ancient people first noticed the white tail streaking through the night starry sky. We remember the date when the comet flies past the Earth once a century or even less often and remember all our lives. In the middle ages in Europe, the appearance of comets was often linked to various natural disasters and diseases. In religion, these heavenly bodies also play an important role. For example, in the New Testament, the comet heralded the birth of Christ.
Astronomers find comets also interesting and fascinating space objects, because they are witnesses of great historical events and even carry evidence of them.
The comet is a relatively small object in our solar system, usually having a diameter of several kilometers. Sometimes called “dirty snowballs” because of their component substances. Usually comets are composed of the following four elements:
Ice (water, ammonia, methane, carbon dioxide)
Some organic materials (e.g., resin)
Rocky ground (optional) Continue reading