Since the XVII century, the most important goal of astronomers has been the study of the Milky Way – this giant collection of stars that Galileo saw through his telescope. The efforts of many generations of observer astronomers were aimed at finding out what is the total number of stars of the Milky Way, determining its actual shape and boundaries, and estimating its size. It was only in the 19th century that it was possible to understand that this is a single system that contains all the visible stars. On an equal footing with all, our Sun enters into this system, and with it the Earth and planets. Moreover, they are far from being located in its center, but on its outskirts.
It took many decades of careful observation and deep thought before the structure of the Galaxy was revealed to astronomers in its entirety. So they began to call the star system that we see – of course, from the inside – like a strip of the Milky Way. (The word “galaxy” is derived from the Greek “galacticos”, which means “milky.”)
It turned out that the Galaxy has a fairly regular structure and shape, despite the apparent raggedness of the Milky Continue reading
The formation of astronomy as an exact science began thanks to the work of the outstanding Greek scientist Hipparchus. He first began systematic astronomical observations and their comprehensive mathematical analysis, laid the foundations for spherical astronomy and trigonometry, developed the theory of the motion of the Sun and the Moon, and on its basis – methods for predicting eclipses.
Hipparchus discovered that the apparent movement of the sun and moon in the sky is uneven. Therefore, he came to the point of view that these luminaries move uniformly in circular orbits, but the center of the circle is shifted relative to the center of the Earth. Such orbits were called eccentrics. Hipparchus compiled tables by which it was possible to determine the position of the sun and moon in the sky on any day of the year. As for the planets, according to Ptolemy, he “made no other attempt to explain the motion of the planets, but was content to tidy up the observations made before him, adding to them even more of his own. He limited himself to pointing out to his Continue reading
Despite the high level of astronomical information of the peoples of the ancient East, their views on the structure of the world were limited to direct visual sensations. Therefore, in Babylon, views have developed that the Earth has the appearance of a convex island surrounded by the ocean. Inside the Earth, as if there is a “kingdom of the dead.” The sky is a solid dome resting on the earth’s surface and separating the “lower waters” (the ocean flowing around the earth’s island) from the “upper” (rain) waters. Celestial bodies are attached to this dome, as if gods live above the sky. The sun rises in the morning, leaving the eastern gate, and sets through the western gate, and at night it moves underground.
According to the ideas of the ancient Egyptians, the Universe looks like a large valley, stretched from north to south, in the center of it is Egypt. The sky was likened to a large iron roof, which is supported on pillars, on it in Continue reading
In the solar system there are many different types of free celestial bodies that do not have their own orbits. Such bodies can be asteroids, meteorites, comets, as well as free moons that do not belong to the solar system. In Space, there is also enough “garbage” – debris destroyed by a collision or explosion of celestial bodies. It has long been known that meteorites and other celestial bodies often fall on Earth, moons, and other planets. The earth and other planets are well protected from such “bombing” with their atmosphere, in which most of the small falling objects burn up. But the moons that do not have an atmosphere are literally dotted with impact craters. For example, the satellite of Saturn Mimas in the photo on the left, taken by Cassini in 2005, almost all is covered with craters from the smallest to the gigantic. The sun is not only an exception, but, on the contrary, due to its gigantic attraction, it is thousands of times more likely to undergo such Continue reading
Venus was known to people from ancient times. (See a brief description of this planet and interesting facts about it.) It received its modern name in honor of the Roman goddess of beauty, whom the Greeks called Aphrodite. The Babylonians called this planet Astarta, also named after the goddess of love. In ancient China, Venus was designated as the “golden star” and associated with the “element of gold.” In ancient India, Sura (Ushanas Kawya), the mentor of the asura demons, rivals of the Indian gods, was considered the lord of Venus.
Venus rises in the sky either in the evening or in the morning. The ancient Greeks long considered the “evening” and “morning” star two different bodies, calling the first Hesperus (“Evening”), and the second Continue reading