An astronomical instrument is a term used to describe equipment and instruments used for observing celestial objects and demonstrating celestial phenomena.

These instruments include ground-based and space-based telescopes, radiation receivers, planetariums, and sundials.

The earliest known astronomical instrument was the Skaphe, a bowl-shaped sundial, invented by the ancient Greek astronomer Aristarchus.

In modern and contemporary astronomy, telescopes are the most important astronomical instruments.

The vast majority of celestial objects explored and studied in modern astronomy, with the exception of a few solar system objects, appear as very faint sources of cosmic radiation.

Astronomical instruments that collect cosmic radiation are called astronomical telescopes.

There are many types of astronomical telescopes, such as optical, infrared, radio, ultraviolet, X-ray, and v-ray telescopes, distinguished by the wavelength of observation.

Telescopes in a particular wavelength band can be further divided into different types according to differences in construction or function.

In addition, there are various special telescopes designed for more specific purposes, such as solar magnetic field telescopes and spectroscopic survey telescopes.

The primary functions of astronomical telescopes are to concentrate light or waves and to improve resolution.

The size of the light-gathering capability is proportional to the area of light gathering, which is proportional to the square of the aperture of the light passing through.

The larger the aperture, the stronger the light-gathering ability, and the better the ability to observe faint cosmic radiation sources.

The resolving power of an astronomical telescope is also proportional to its aperture.

Starting from the mid-19th century, photographic negatives were used in astronomical instruments, and in the 20th century, photoelectric devices such as phototubes, photomultiplier tubes, and charge-coupled devices were gradually introduced.

The radiation receivers fitted to different wavelengths and types of astronomical telescopes can vary considerably.

The faint nature of cosmic radiation requires a certain cumulative acquisition time.

The orientation of celestial bodies on the celestial sphere changes over time due to Sunday motion, which requires astronomical instruments to be able to track the observed cosmic radiation source.

The equipment that carries the astronomical telescope to track celestial objects is called a device.

Astronomical telescopes are usually carried by equatorial devices, which are driven and tracked mechanically and electrically.

The new generation of large telescopes tends to use geostrophic devices operated by computer control.

Astronomical instruments play a crucial role in modern astronomy, allowing astronomers to observe and study celestial objects and phenomena.

The continuous advancements and developments in technology have led to significant improvements in astronomical instruments, enabling astronomers to gather more accurate and detailed data about the universe.