Astrolabe is an ancient astronomical instrument

Many people think that our civilization is a source of constant progress, and all the most interesting discoveries and developments are yet to come. However, profound philosophical works, some masterpieces of architecture and even devices created long before us clearly highlight the incompleteness of this concept. Ancient scientists also knew a lot, they created structures and things, the principle of work and the purpose of which is incomplete. A clear consistency of the functioning of certain devices with the laws of physics and the irrefutability of the information obtained with their help are often shrouded in legends. The number of such instruments includes astrolabe, an ancient astronomical instrument.

Appointment

As is clear from the name ("astra" in Greek means "star"), the device is associated with the study of celestial bodies. Indeed, astrolabe is a tool that allows us to calculate at what altitude the stars and the Sun are relative to the surface of our planet, and on the basis of the obtained data to determine the location of a particular earthly object. In long travels by land and sea, the astrolabe helped determine the coordinates and time, sometimes served as the only landmark.

Structure

The astronomical instrument consists of a disk representing a stereographic projection of the starry sky, and a circle with a high rim in which the disc is nested. The base of the device (the element with a bead) has in the central part a small hole, as well as a suspension ring, necessary to facilitate the orientation of the entire structure relative to the horizon. The middle part is made up of several circles with lines and points on them defining the latitude and longitude. These discs are called tympanum. The goniometer astronomical instrument had three such elements, each of them was suitable for a certain latitude. The order in which the tympans were embedded was dependent on the terrain: the upper disc should contain the projection of the sky corresponding to this section of the Earth.

Above the tympani there was a special lattice ("spider"), equipped with a large number of arrows indicating the brightest stars indicated on the projection. Through the holes in the center of the tympanum, the lattice and the base, there was an axle fastening the parts. Alidade was attached to it, a special ruler for calculations.

The accuracy of the astrolabe's testimony is striking: some instruments, for example, are capable of showing not just the movement of the Sun, but also the deviations that periodically arise in it. It is interesting that an ancient astronomical instrument was created at the time when the geocentric picture of the world dominated. However, the idea that all the celestial bodies spin around the Earth did not prevent the ancient scientists from creating such an accurate instrument.

A bit of history

The astronomical instrument has a Greek name, but many of its components bear names of Arab origin. The reason for this seeming inconsistency is in the long journey that the device overcame during its period of formation.

The history of the development of astronomy, like many other sciences, is inextricably linked with ancient Greece. Here about two centuries before the beginning of our era a prototype of an astrolabe appeared. Its creator was Hipparchus. Already in the second century after the birth of Christ, the description of a similarly astrolabe goniometer was made by Claudius Ptolemy. He also built a tool capable of determining the location of stars in the sky.

These first instruments differed somewhat from the astrolabes, as they are represented by modern man and which are exhibited in many museums around the world. The first tool of the customary structure is the invention of Theon of Alexandria (4th century AD)

Eastern sages

The history of the development of astronomy during the early Middle Ages began to unfold in the territory of Islamic states. This was due to the persecution of scientists by the church, with the attribution of instruments, similar to the astrolabe, of satanic origin.

Arabs have perfected the instrument, they began to apply it not only to determine the location of stars and orientation in the terrain, but also as a time meter, a tool for some mathematical calculations, a source of astrological predictions. The wisdom of the East and the West merged, the result was the astrolabe device, which combined the European heritage with Arab thought.

Pope and devil instrument

One of the Europeans who wanted to revive the astrolabe was Herbert of Aurillac (Sylvester II), who briefly occupied the post of Pope. He studied the achievements of Arab scholars, learned to use many tools that had been forgotten since antiquity or banned by the church. His talents were recognized, but the connection with alien Islamic knowledge contributed to the emergence of a number of legends around him. Herbert was suspected of having a succubus and even a devil. The first gave him knowledge, and the second helped to take such a high position in the church hierarchy. The impurity was attributed to his ascent. Despite all the rumors, Herbert managed to revive a number of important instruments, including the astrolabe.

Return

After a while, in the XII century, Europe again began to use this device. At first, only the Arabian astrolabe was in motion. This was for many a new tool and only for some - a forgotten and modernized heritage of ancestors. Gradually began to appear analogues of local production, as well as long scholarly works related to the use and device of the astrolabe.

The peak popularity of the device fell on the era of the Great Discoveries. In the course was a marine astrolabe, helping to determine where the ship was. True, it had a feature that negated the accuracy of the data. Columbus, like many of his contemporaries who traveled the water, complained that this device can not be used in pitching conditions, it is effective only when the ground is stationary or the sea is completely calm.

A certain value for seafarers the device nevertheless represented. Otherwise, one of the ships on which the expedition of the famous explorer Jean Francois La Perouse would set off on a trip would not be named in his honor. The ship "Astrolabe" - one of two, participated in the expedition and mysteriously disappeared in the late eighteenth century.

Decoration

With the advent of the Renaissance, "amnesty" received not only various devices for exploring the world around, but also objects of decor, a passion for collecting. Astrolabe is an instrument, among other things, often used to predict the fate of the movements of the stars, and therefore it was decorated with various symbols and signs. Europeans have adopted from the Arabs the habit of creating accurate in terms of measurements and elegantly visible devices. Astrolabe began to appear in the collections of courtiers. Knowledge of astronomy was considered the basis of education, possession of the device emphasized the scholarship and taste of the owner.

Crown of the collection

Beautiful instruments were inlaid with precious stones. Pointers were given a shape of leaves and curls. Gold and silver were used for decorating the instrument.

Some masters devoted themselves almost entirely to the art of creating astrolabes. In the 16th century the most famous of them was the Flemish Gualterus Arsenius. For collectors, his products were the standard of beauty and grace. In 1568 he was ordered another astrolabe. The device for measuring the position of stars was intended for Colonel of the Austrian Army Albrecht von Wallenstein. Today, this copy is kept in the museum. M.V. Lomonosov Moscow State University.

Shrouded in mystery

Astrolabe, one way or another, slips in many legends and mystical events of the past. Thus, the Arab stage of its history gave the world the myth of treacherous sultans and the scientific abilities of the court astrologer Biruni. The ruler, after a hidden reason in the ages, took up arms against his predictor, decided with the help of cunning to get rid of him. The astrologer had to specify exactly which way out of the hall his master would use, or to suffer a fair punishment. In his calculations, Biruni took advantage of the astrolabe and, writing the result on a scrap of paper, hid it under the carpet. The tricky Sultan ordered the servants to cut a passage in the wall and went through it. Returning, he opened the paper with a prediction and read a message there, foreseeing all his actions. Biruni was acquitted and released.

The inexorable progress of progress

Today astrolabe is part of past astronomy. Orientation on the ground with its help has ceased to be appropriate since the beginning of the XVIII century, when the sextant appeared. Periodically, the device is still used, but even a century later or a little more astrolabe finally moved to the shelves of collectors and lovers of antiquities.

Modernity

Approximate understanding of the device and the functioning of the device gives its modern descendant - the planisphere. This is a map on which stars and planets are painted. Its components, stationary and mobile parts, in many respects resemble the base and disk. To determine the correct position of the luminaries in a particular part of the sky, an upper moving element is necessary, corresponding in parameters to the desired latitude. The astrolabe is similarly oriented. With your own hands, you can even make a likeness of the planisphere. Such a model will give an idea of the possibilities of its ancient predecessor.

Living legend

A ready astrolabe can be bought in souvenir shops, sometimes it appears in collections of decorative items that take as a basis the style of sim-punk. Unfortunately, working instruments are difficult to find. Planisfery are also rare on the shelves of our stores. Interesting specimens can be found on foreign websites, but such a mobile map will cost like the same cast-iron bridge. Self-design of the model may be a matter that requires a lot of time, but the result is worth it and will surely please the children.

The starry sky, so comprehensively occupied with the minds of the ancients, impresses with its beauty and mystery and modern man. Such devices as the astrolabe make it a little closer to us, a little more understandable. The museum or souvenir version of the device also makes it possible to feel the wisdom of our ancestors, and two thousand years ago they created tools that allow us to accurately display the world and find our place in it.

Today, astrolabe is a stylish souvenir, interesting for its history and attracting the look of unusual design. Once it was a significant breakthrough in astronomy, allowing to relate the position of celestial bodies to the terrain, almost the only chance of understanding where a traveler was lost in the vastness of the ocean or the desert. And let the device significantly loses its functional analogues to its modern counterparts, it will always be a significant part of history, an object wrapped in a romantic veil of mystery, and therefore is unlikely to get lost in the centuries.