Who invented the astrolabe? In which country and when

Astrolabe: It is an ancient astrological computer that solves the problem of time and tells the position of the stars in the sky. Although it was invented by the ancient Greeks, it was the Islamic prophet who first invented the portable astrolabe, which was a revolutionary astrological discovery.

The inventors of legend include Hibachas, Apollonius, and others, but there is a lack of sufficient evidence. Probably the earliest account of the astrolabe is Ptolemy's Treatise on the Supreme, in which he devotes an entire section to detailing the construction and use of the astrolabe. He did not make it clear whether this was a previous invention or his own.

However, the structure of the astrolabe described by him is very consistent with what later generations have seen.

The main body of the astrolabe, consisting of a disk surface and a copper ring. The upper grey ring is called a "web ring" (Latin rete, from the Arabic word for "spider web"), and it rotates on the north celestial axis above the lower disk. The pole is also on the axis of the North Celestial Pole and can be rotated arbitrarily on the plane of the astrolabe.

Using the geometric projection method, the horizon coordinate network is projected on the astrolabe disk. Special attention should be paid to the determination of the position of the zenith in the horizon coordinate network - the angular distance between the zenith and the north celestial pole (or the position of the north celestial pole in the astrolabe horizon coordinate network) varies according to the local geographical latitude. In other words, any of these astrolabes can only be used at a specific geographical latitude to obtain accurate data.

Curved and pointed stars (some charts are also made in a straight pointed shape) are used to indicate special stars (such as those that are particularly bright or have special astrological significance).

The astrolabe was an instrument used in ancient times to measure the height of celestial bodies. Probably born in the 3rd century BC Astrolabe (circa 1572).

Dried meat. The oldest astrolabe is a wooden disc with a ring, the degree of an arc engraved on the edge. Later astrolabes were often changed to metal.

One side of the disk is equipped with a speculum that rotates around the center, and the disc is hung vertically during observation, from which the human eye is pointed at the sun or star, and the height of the measured object can be obtained from the scale on the edge of the disk. The other side of the disk is engraved with a star map, a horizon coordinate network and a grid related to the ecliptic and equator, and through the observation of the sun and other celestial bodies and some conversions, the observation time and latitude of the observation can also be obtained. The astrolabe can be used for teaching, navigation, and surveying, and has long been popular in Europe and Islamic countries.

It was only replaced by the sextant after the middle of the 18th century.