Halley's comet is the most famous comet that can be observed from Earth. Many stories and superstitions are associated with her. In different eras, people perceived its periodic occurrences differently. She was considered both a sign of God and a devilish curse. A bright star with a luminous tail inspired horror and promised changes.
Discovery of the comet
The comet was observed in antiquity. We have heard of it, dated 240 BC. For a long time, it was believed that comets are perturbations and vortices in the earth's atmosphere. Tito Brahe, a Danish astronomer, established by measuring in 1577 that the orbit of Halley’s comet lies outside the moon, in space. But it was just not clear whether the comet flies along a rectilinear trajectory or moves in a closed orbit.
Halley's research
The answer to this question was given by the English astronomer Edmund Halley in 1687. He noticed that the comet was either approaching the Sun or moving away from it, which did not correspond to rectilinear motion. Compiling a catalog of the orbits of comets, he drew attention to the records of observations of scientists who lived before him and made the assumption that comets 1531, 1607, 1687 are the same celestial body. After calculating in accordance with Newton's laws, Halley predicted the appearance of a comet in 1758. This prediction came true after his death, though with a delay of 619 days. The fact is that the period of revolution of Halley's comet depends on the gravitational interaction of the planets of the giants Jupiter and Saturn, and according to modern research, it can be from 74 to 79 years. The comet, the frequency of occurrence of which was discovered by Halley, was named after him.
Comet Properties
Halley's comet belongs to the class of short-period comets. These are comets with a rotation period of less than 200 years. It rotates around the Sun in an elongated elliptical orbit, the plane of which is tilted to the ecliptic plane by 162.5 °, and it moves in a direction that is opposite to the movement of the planets. The speed of the comet relative to the Earth is the highest among all the bodies of the solar system - it is 70.5 km / s. Mathematical modeling shows that the comet has been in orbit for approximately 200,000 years. But these data are approximate, since the influence of the Sun and other planets is very diverse and unpredictable deviations are possible. Its expected life in orbit is 10 million years.
Comet Halley belongs to the family of comets of Jupiter. Currently, the catalog of such celestial bodies includes 400 comets.
The composition of the comet
At the last appearance of the comet in 1986, research probes Vega-1, Vega-2 and Giotto were launched to it. Thanks to their research, it was possible to determine the composition of the comet. This is mainly water, carbon monoxide, methane, nitrogen and other frozen gases. The evaporation of particles leads to the formation of a comet tail, which reflects sunlight and becomes visible. The configuration of the tail can change under the influence of the solar wind.
The density of the comet is 600 kg / m 3 . The core consists of a pile of debris. The core consists of non-volatile materials.
Research on Halley's comet continues today.
Comet appearances
In the 20th century, Halley's comet appeared in 1910 and in 1986. In 1910, the appearance of a comet caused a panic. In the spectrum of the comet, cyan, a poisonous gas, was discovered. The properties of potassium cyanide, the strongest poison, were already well known. He was popular with suicides. All of Europe in horror was waiting for the arrival of a poisonous celestial guest, apocalyptic forecasts were published in newspapers, poets dedicated poetry to her. Journalists competed in wit, and a wave of suicides swept across Europe. Even Alexander Blok wrote in a letter to his mother about the comet:
Its tail, consisting of a synerod (hence the blue eye), can poison our atmosphere, and all of us, having reconciled before death, will sweetly fall asleep from the bitter smell of almonds on a quiet night, looking at a beautiful comet ...
Entrepreneurial charlatans put up for sale "antikomet tablets" and "antikomet umbrellas", which were instantly sold out. The newspapers had proposals for the rental of submarines during the flight of the comet. The comic ad said that you will spend several days under water, and then the whole Earth will belong to you undividedly. People discussed the possibility of escape, hiding in a barrel of water.
Comet Writers
Mark Twain wrote in 1909 that he was born in the year the comet appeared (1835), and that if he does not pass away at her next visit, this will greatly disappoint him. This prediction came true. He died in 1910 when the comet was perihelion. Voloshin, Blok wrote about the comet.
Igor Severyanin said that "Premonition is more languid than a comet."
Cataclysms and comet
With the advent of Halley's comet, humanity has been linked to the disasters occurring on Earth. In 1759 there was a huge eruption of Vesuvius, the king of Spain died, a wave of hurricanes and storms swept across the world. In 1835, a plague epidemic erupted in Egypt, a powerful tsunami passed in Japan, there was an eruption of a volcano in Nicaragua. In 1910, after the passage of the comet on Earth, massive epidemics began, including the famous "Spaniard", which claimed millions of lives. In India there was an epidemic of bubonic plague. In 1986, an accident occurred at the Chernobyl nuclear power plant, the echoes of which we still feel.
Of course, all this is nothing more than coincidence. Every year, and without the appearance of a comet, natural disasters and man-made disasters occur.
Next comet appearance
In 1986, when Halley's comet was the last time, it disappointed astronomers. The conditions for observing it from Earth over the past 2000 years have been the worst. The comet is best observed at perihelion when its tail is the longest and its nucleus is bright. But this year the comet arrived in February and its perihelion was on the opposite side of the Sun from the Earth, therefore it was closed for observation.
The next time Halley's comet flies is July 2061. It should be clearly visible. You can watch it for 4 months. It will be especially visible at dawn and before sunset.