What is a comet: the history of discoveries, the most famous comets
People who are watching a star falling in the sky may have a question, what is a comet? This word is translated from Greek as “long-haired”. While approaching the Sun, the asteroid begins to heat up and takes on an effective form: dust and gas begin to fly away from the surface of the comet, forming a beautiful, bright tail.
The appearance of comets
The appearance of comets is almost impossible to predict. Scientists and amateurs have been paying attention to them since ancient times. Large celestial bodies rarely fly past the Earth, and such a spectacle is fascinating and frightening. In the story there is information about such bright bodies that sparkle through the clouds, overshadowing even the Moon with its glow. It was with the advent of the first such body (in 1577) the study of the movement of comets began. The first scientists were able to discover dozens of different asteroids: their approach to the orbit of Jupiter begins with the glow of the tail, and the closer the body is to our planet, the brighter it burns.
It is known that comets are bodies that move along certain trajectories. Usually it has an elongated shape, and is characterized by its position relative to the sun.
The comet's orbit may be the most unusual. From time to time, some of them return to the Sun. Scientists say that such comets are periodic: they fly around the planets after a certain period of time.
Since ancient times, any luminous body was called a star, and those behind which tails stretched were comets. Later, astronomers discovered that comets are huge solid bodies, representing large ice fragments mixed with dust and stones. They fly from the far space and can either fly past or rotate around the sun, periodically appearing in our sky. It is known that such comets move in elliptical orbits of very different sizes: some return once in twenty years, and some appear once in hundreds of years.
Scientists know a lot of information about comets of a periodic type. The orbits and time of return are calculated for them. The appearance of such bodies is not unexpected. Among them are short-period and long-period.
The short-period comets, which can be seen in the sky several times in life. Others may not appear in the sky for centuries. One of the most famous short-period comets is Comet Halley. It appears on Earth once every 76 years. The length of the tail of this giant reaches several million kilometers. It flies so far away that it seems to be a strip in the sky. Her last visit was recorded in 1986.
Scientists know many cases of the fall of asteroids on the planet, and not only on Earth. In 1992, the giant Shoemaker Levy came very close to Jupiter and was torn apart by its gravity into numerous pieces. The fragments stretched into a chain, and then moved away from the orbit of the planet. Two years later, the chain of asteroids returned to Jupiter and fell on him.
According to some scientists, if an asteroid flies in the center of the solar system, then it will live for thousands of years until it evaporates, flying once again at the Sun.
Comet, asteroid, meteorite
Scientists have identified the difference in the value of asteroids, comets, meteorites. Ordinary people call these names any bodies seen in the sky and having tails, but this is not correct.From a scientific point of view, asteroids are huge boulders floating in space in certain orbits.
Comets are like asteroids, but they have more ice and other elements. When approaching close to the Sun, comets have a tail.
Meteorites are small stones and other space debris, less than a kilogram in size. They are usually seen in the atmosphere as falling stars.
Comet Hale-Bopp has become the brightest comet of the twentieth century. It was opened in 1995, and two years later it became visible in the sky with the naked eye. In the sky, it could be observed more than a year. It is much longer than the glow of other bodies.
In 2012, scientists discovered the comet ISON. According to forecasts, it should have become the brightest, but, coming to the Sun, could not meet the expectations of astronomers. However, it was called in the media "comet of the century."
The most famous is the comet Halley. She played an important role in the history of astronomy, including helping to deduce the law of aggression. The first scientist who described the celestial bodies was Galileo. His information was processed more than once, changes were made, new facts were added. Once Halley drew attention to the very unusual pattern of the appearance of three celestial bodies with an interval of 76 years and moving on almost the same trajectory.He concluded that these were not three different bodies, but one. Later, Newton used his calculations to build a theory of gravity, which was called the theory of world wideness. The last time Halley’s comet was seen in the sky was in 1986, and its next appearance will be in 2061.
In 2006, Robert McNaught discovered the same celestial body. According to the assumptions, it was not supposed to glow brightly; however, as it approached the Sun, the comet began to rapidly gain brightness. A year later, she began to glow brighter than Venus. Flying near the Earth, the heavenly body made a real spectacle for earthlings: its tail arched in the sky.