The world of the unknown - Onua.org

Even the most General observations of the sky can be concluded that the Sun is among the many stars, the greatest number of which are located in the direction of the milky Way. Apart from its bright band of stars much less. Stars of the milky Way and visible separately form a single star system.

Basic information about the galaxies gathered in multiple directories. The first galactic directory was created in 1784 Charles Messier and P. Masinam. It includes 108 nebulae, which the authors nazvali motionless, not to be confused with comets moving. Objects included in the Messier catalogue, denoted by the letter M with a serial number. So, for example, M31 designation of the Andromeda nebula. Currently widely used "New General catalogue" Dreyer (its first part was published in 1888), it included about 13,000 objects. Galaxy M31 in the directory Dreyer designated NGC 224. In the late 60's. our century were created "Morphological catalog of galaxies" (group B. A. Vorontsov-Velyaminov) and "the Second bibliographic catalogue of bright galaxies" (group Gokudera). These directories contain tens of thousands of objects.

When autumn evenings get darker in the sky is visible wide shimmering band. This milky Way - a giant arch spanning the entire sky. "The heavenly river" is called the milky Way in Chinese tales. The ancient Greeks and the Romans called it "Heavenly road". The telescope gave the opportunity to clarify the nature of the milky Way. It is the radiance of the innumerable stars are so distant from us that they individually impossible to distinguish with the naked eye.

Galaxies are huge star systems that contain from several millions to hundreds of billions of stars. In addition to stars in the composition of galaxies are the interstellar gas of interstellar dust, cosmic rays. The amount of gas in galaxies mass substantially less than the stars and different from galaxies of various types. Number of other types of substances still substantially less than gas.

To this conclusion came the American astronomer Edwin Hubble, which repeated the experiments predecessors on a much more extensive observational material. In 1929 he said that not only established systematic red shift of spectral lines of galaxies, but also defined the law on which the speed of removal of galaxies from us increase as the distance increases. Thus it was proved that in the world of galaxies there is a Gulf stream, which carries them on outer space.

Every cubic centimeter of space contains about 500 photons. Substances on the same volume accounted for a much lower: about 10'6 baryons (the so-called heavy elementary particles, including the protons and neutrons). Since photons don't disappear (the space between galaxies is transparent), the ratio of photons to the number of baryons in the course of expansion of the Universe is preserved. But the energy of the photons decreases over time because of the red shift.

The spectacle of the starry night sky filled with stars, mesmerize any man whose soul is not lazy and not dry completely. The mysterious depths of Eternity opens in front of the startled human eye, causing thinking about the original, where it all started...

During the formation of the Sun conditions in protoplanetary disk were not, of course, the same at different distances from the Sun and have changed over time. The matter remained cold just away from the Sun. Near him was strongly heated and dust suffered complete or partial evaporation. Only later, when the gas is cooled down, she condense again, but most volatile substances contained in interstellar dust appeared to be lost in the new dust is not already included. The evolution of the protoplanetary disk led to the formation in it of planetesimals, which later grew planet. The composition of planetesimals formed at different heliocentric distances, due to the different composition of dust, gone to their building, was different.

Asteroids are so small that the force of gravity on them void. She was not able to give them a shape of a ball, what makes planets and their large satellites, crushing and stamping their substance. A great role is played by the phenomenon of fluidity. High mountains on the Earth at the foot of the "creeping", because the strength of the rocks is insufficient to withstand many tons per 1 cm3,and stone, not fractions, not raskalyvanii, flows, albeit very slowly.

Asteroids - through cold, lifeless body. In the distant last their bowels could be warm and even hot due to radioactive or any other heat sources. Since then, they have long cool. However, internal heat never warmed surface: the flow of heat from the interior was very small. The surface layers remained cold, and only clash from time to time caused short-term local heating.

In 1876, when it was known only about 150 asteroids, D. Kirkwood tried to understand "chaos" asteroid orbits and found about 10 groups of asteroids, each of which consisted of only 2-3 members moving on similar orbits. Among them were, for example, 3 Juno and 97 of the Clot.

The orbits of most of the numbered minor planets (98%) are located between the orbits of Mars and Jupiter. Their mean distances from the Sun ranges from 2.2 to 3.6 A. that is, They form the so-called main asteroid belt. All the small planets as big move in the forward direction. The periods of their circulation around the Sun are depending on the distance from three to nine years. It is easy to count, that the linear speed of approximately 20 km/S.

Asteroids is a small celestial body in size from a few metres to thousands of kilometres. In General, between them and meteoric bodies there is no clear difference. The number of such bodies in the Solar system more than they do less. Many scientists believe that most meteoroids are chips of asteroids. Asteroids, and meteorites consist of iron, Nickel and various stony rocks. They are close to the planets of terrestrial group.

The beginning of the 19th century. In Palermo, in Sicily, Italian astronomer by gioseppe Piazzi for many years led the observations of the positions of the stars for compiling star catalogue. The work was nearing an end. And now, the first night of the XIX century, on 1 January 1801, Piazzi discovered in the constellation Gemini weak star, with a brightness of about 7m, which for some reason was not in its own directory or in the directory Christian Mayer available to Piazza.

Asteroids first gave the names of the heroes of the Roman and Greek mythology, and then discoverer have the right to call it whatever you like, though his name. At first, the name was given only to women. Only asteroids with unusual orbit, got men (for example, Icarus, coming closer to the Sun, mercury). After, and it has ceased to be respected.