In the 17th century, an instrument called a telescope was invented. What is it for? Thanks to him, it became possible to observe the movement of planets, the formation of galaxies and the study of the mysterious. The view through the telescope is incredible and... it is available to anyone person interested in astronomy.

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Operating principle of the device

What is a telescope ? This is a tool with which you can observe a distant object, thanks to certain lenses and electromagnetic radiation from the object itself. How many times does this technique increase?

It all depends on the model: the simplest children's telescopes are 10 times, and the most powerful Hubble is more than 1000 times.

The telescope works by refraction of light and a set of correctly selected lenses. It's all about the ability of the optics to collect light, and the larger its lens, the more light it collects and, accordingly, the better it transmits the image.

From this it follows that it is light, or rather its quantity, plays a role in the quality of the final image and its details. The diaphragm is responsible for collecting light - a plate with a hole through which light rays pass, so when purchasing optics you should pay great attention to this particular detail.

Important parameters

In addition to the diaphragm, there are others, no less important details. These include:

1. Lens diameter – it is responsible for the instrument’s ability to collect light: the larger this parameter, the smaller the details can be seen.
2. Focal length is the distance from the lens to the focus, and it is responsible for the magnification power of the device.
3. An eyepiece is two or more lenses held together by a cylinder whose job is to magnify the resulting image.
4. Lens – forms the image. A Barlow lens is often used and can double the focal distance.
5. Diagonal mirror - with its help you can deflect the flow of light at an angle of 90°. This is convenient when you need to observe bodies located strictly vertically above the observation site.
6. Viewfinders are an additional tool that is used in conjunction with the main equipment.
7. Straightening prisms - since images come out upside down, these details help to correct and view them at an angle of 45°.
8. Mounts are devices that can be used to secure and point equipment.

When purchasing a device, you should carefully read these details to choose the best option for your purpose.

Kinds

Like any optics, there are telescopes:

1. Amateur optics are optics that can magnify objects several hundred times;
2. Professional scientific ones are higher quality and more powerful devices.

Types of telescopes

Professional and scientific are divided on the:

• optical – magnify more than 250 times, but after this threshold the quality of the pictures begins to deteriorate;
• radio telescopes - they measure the energy of objects and provide the highest quality image;
• X-ray;
• Gamma-ray telescopes.

In addition, they are divided and by optical class:

• refractive – they use a large lens as a light-gathering part;
• reflective - with a concave mirror that collects the light flux and forms a picture;
• mirror-lens - in this optics both types of light-collecting parts are used simultaneously.

Some instruments in space are needed to take better pictures. They grouped by radiation frequencies:

• gamma;
• X-ray;
• ultraviolet;
• visible;
• infrared;
• microwave;
• radio emission.

note! A certain optical device captures the radiation and, based on it, builds a picture that is transmitted to the observatory. On Earth, the most popular devices are reflex technology, which is used by both amateurs and professionals.

What is visible

Optical instruments are necessary for space exploration. The most convenient telescope for this is After all, it can be seen quite clearly:

1. The moon - with special optics you can see its detailed relief, and even its ashen light;

Telescope and starry sky

Available for study:

• Mercury - it will be visible like a star, and only with lenses larger than 100 mm in diameter can you observe the phase of the planet in the form of a small crescent;
• Venus is the brightest celestial body, it is easy to see the phase of the planet using any technique;
• - will be visible as a small circle and only 2 times a year;
• Jupiter - even with a homemade telescope, Galileo was able to examine its 4 satellites, so it is easy to fully examine this planet and its rings;
• Saturn is the most beautiful planet in the system. It will be visible along with the rings even through 50-60 mm lenses;
• Uranus and Neptune - these distant planets, even with professional lenses, look like small stars or blue disks.

Important! You should never try to look at it with a telescope. This will cause permanent eye damage and equipment damage.

What else is possible see through a telescope:

1. Star clusters - they can be viewed through optics with any diameter, but only through lenses with a diameter of 100-130 mm will individual stars be visible.
2. Galaxies - distant systems of planets and stars are visible even with simple binoculars, but with lenses of 90-100 mm, you can already observe their shape, and with lenses with a diameter of 200-250 mm you can even see the stellar arms.
3. Nebulae are clouds of gas and dust that are illuminated by stars. With amateur equipment, you can see them as faint spots, but more professional equipment will show their gas structure.
4. Double stars - stars can not only be lonely like the Sun, but also represent a system of two, three or more copies. With special instruments, even double stars can be seen as points, since they are located at a great distance from the Earth.
5. Comets—“tailed guests”—can be seen with your eyes, but through eyepieces you can even see their tails in detail.

Stargazing is a fascinating activity that not only develops, but also gives an idea of ​​the entire Universe. And so that what you see can be understood, you should use it in these classes. special star map.

How to choose a device for observing planets

Due to the abundance of optical instruments on the market, it is quite difficult to decide which technology to choose for observing planets. To simplify this process, you should pay attention to the diameter of the pipe - it is the aperture (diameter) that determines everything optical capabilities of the device.

The larger it is, the more light the lens transmits and, accordingly, the larger and better the final image and the ability to enlarge objects.

To calculate the maximum magnification, you should use the formula: 2x D, where D is diametrical millimeters. You should also consider the ultimate goal: will the technology be used to observe nature or space? What is the level of an astronomer? Based on the answers, you should choose. You should pay attention on the:

• aperture;
• focal length;
• lenses or mirrors;
• presence of a reflector.

The most important parameter of all is the aperture. What is this? This is the diameter of the lens. Why do you need the correct size? Based on it, you can simply look at distant spots, or in detail study the celestial body. These models should be chosen for novice astronomers:

• Sky-Watcher;
• Arsenal-GSO;
• Celestron.

What is best for a child?

Are there any differences between adult and children's technology for observing the sky? Of course, and the main one is increase. Children's specimens never will not enlarge the image just like the cheapest and simplest adult. But the advantages of children's options are in their size - they are all quite compact and easy to transport. Through such lenses you can see:

• Earth's satellite and its relief;
• constellations;
• all the planets in the solar system;
• Milky Way;
• Clusters of stars;
• nebulae.

Does a child need a telescope?

Of course, if he shows interest in science and astronomy.

Despite the small image, the child will be able to see almost all celestial bodies, which will not only satisfy his interest, but also encourage him to learn and explore the world.

Therefore, you should approach the choice carefully and pay attention to some characteristics of the purchased equipment:

• system: lens or mirror;
• focal length (ideal for a child is from 520 to 900 mm);
• lens diameter (from 40 to 130 mm).

Which models are ideal for a baby? Can choose:

• Bresser Junior;
• Levenhuk;
• Bresser Space;
• Sky-Watcher Dob.

Which telescope should I choose for my child? It is best to take a refractor in models specifically for children. It is easy to use and does not require settings.

Advice! There are devices with an auto-guidance system that can search for objects in the sky independently according to specified parameters.

For photography

How to photograph through such optics? For this you need a telescope and any camera. Photos can be taken even with the simplest model and mobile phone. For example, ocular projection is obtained by shooting even with a phone through the eyepiece. For better photographs, you will need a camera with a lens that can be removed, and a tripod, which should be used to avoid shaking hands. Photographs are also taken through an adjusted eyepiece, and it is best to shoot in clear weather to obtain a clear and high-quality image.

Why are telescopes needed, their functions

What can you see with a telescope

Conclusion

The ability to see does not come immediately. Experienced astronomers spend many hours using telescopes before they can independently discern small objects or distant stars. This talent develops just like any other, so you need to be patient and practice regularly.

OPTICAL TELESCOPE- used to obtain images and spectra of space. objects in optical range. The radiation of objects is recorded using photographs. or TV cameras, electro-optical converters, charge-coupled devices. The effectiveness of O. t. is characterized by extreme magnitude, achievable on a given telescope for a given signal-to-noise ratio (accuracy). For weak point objects, when the noise is determined by the background of the night sky, it depends mainly. from attitude D/, Where D- aperture size O. t., - ang. diameter of the image it produces (the larger D/, the greater, all other things being equal, is the limiting magnitude). Working in optimal O. t. conditions with a mirror diam. 3.6 m has a maximum magnitude of approx. 26 T with an accuracy of 30%. There are no fundamental restrictions on the maximum stellar magnitude of terrestrial stars.
Astr. O. t. was invented by G. Galilei in the beginning. 17th century (although he may have had predecessors). His O. t. had a scattering (negative) eyepiece. Approx. at the same time, J. Kepler proposed O. t. with positive. an eyepiece that allows you to install a cross of threads in it, which significantly increased the accuracy of sighting. Throughout the 17th century. astronomers used optical telescopes of a similar type with a lens consisting of a single flat-convex lens. With the help of these orbitals, the surface of the Sun (spots, faculae) was studied, the Moon was mapped, and the satellites of Jupiter and the rings and satellites of Saturn were discovered. In the 2nd half. 17th century I. Newton proposed and manufactured an optical lens with a metal lens. parabolic mirrors (reflector). With the help of a similar O. t. U. Herschel discovered Uranus. Progress in glass melting and optical theory. systems made it possible to create in the beginning. 19th century achromatic lenses (see Achromat).ABOUT. i.e. with their use (refractors) they had a relatively short length and gave a good image. With the help of such optical telescopes, distances to the nearest stars were measured. Similar tools are still used today. The creation of a very large (with a lens diameter of more than 1 m) lens refractor turned out to be impossible due to the deformation of the lens under the influence of its own. weight. Therefore, in con. 19th century The first improved reflectors appeared, the lens of which was a concave parabolic mirror made of glass. shape, coated with a light-reflecting layer of silver. With the help of similar O. t. in the beginning. 20th century Distances to nearby galaxies were measured and cosmological discoveries were made. redshift.
The basis of optical technology is its optics. system. Ch. mirror - concave (spherical, parabolic or hyperbolic). Parabolic the mirror builds a good image only on optical. axis, hyperbolic - does not build it at all, so lens correctors are used that increase the field of view (Fig., A). Optical option system is the Cassegrain system: a beam of converging rays from Ch. parabolic the mirror is intercepted to the focus by a convex hyperbolic. mirror (Fig. b). Sometimes this focus is carried out with the help of mirrors into a stationary room (coudet focus). Working field of view, within the optical range. modern system large O. t. builds undistorted images, does not exceed 1 - 1.5°. Wider-angle O. t. are performed according to the Schmidt or Maksutov scheme (mirror-lens O. t.). In O. t. Schmidt correction. the plate is aspherical. surface and is placed at the center of curvature of the spherical. mirrors Maksutov systems have aberrations (see. Aberrations of optical systems)ch. spherical mirrors are corrected by a meniscus with a spherical surfaces. Diameter mirror-lens mirrors O. t. no more than 1.5 - 2 m, field of view up to 6°. The material from which O. t. mirrors are made has low thermal properties. coefficient expansion (TCR) so that the shape of the mirrors does not change when the temperature changes during observations.

Some optical designs of large modern reflectors: A- direct focus; b- Cassegrain trick. A- main mirror, IN- focal surface, arrows indicate the path of rays.

Optical elements of optical telescopes are fixed in the optical telescopic tube. To eliminate decentering of the optics and prevent deterioration in image quality when the pipe is deformed under the influence of the weight of optical telescopic parts, the so-called. compensation pipes type that do not change the direction of the optical fiber when deformed. axes.
Installation (mounting) of the O.T. allows you to point it at a selected space object. object and accurately and smoothly accompany this object in its daily movement across the sky. The equatorial mount is widespread: one of the axes of rotation of the O. t. (polar) is directed towards the celestial pole (see. Astronomical coordinates), and the second is perpendicular to it. In this case, the object is tracked in one motion - rotation around the polar axis. With an azimuth mount, one of the axes is vertical and the other is horizontal. The object is tracked by three movements simultaneously (according to a program specified by the computer) - rotations in azimuth and altitude and rotation of the photographic plate (receiver) around the optical lens. axes. An azimuthal mount makes it possible to reduce the mass of the moving parts of the pipe, since in this case the pipe rotates relative to the gravity vector in only one direction. O.T. mount bearings provide low static friction. Usually hydrostatic is used. bearings: rotation axes of the O.T. float on a thin layer of oil supplied under pressure.
O. t. installed in special. towers. The tower must be in thermal equilibrium with the environment and with the telescope. O.t., intended for observations of the Sun, are installed in high towers - to reduce the influence of turbulence near the soil heated by the Sun, which noticeably worsens the image quality. Raising an optical telescope intended for night observations to a height of 10–20 m does not improve image quality (as was previously assumed).
Modern O. t. can be divided into four generations. The 1st generation includes reflectors with a main glass (TKR7 x 10 -6) parabolic mirror. shapes with a thickness to diameter ratio (relative thickness) of 1/8. Focuses - direct, Cassegrain and coude. The pipe - solid or lattice - is made according to the principle of max. rigidity. Bearings are usually ball bearings. Examples: 1.5- and 2.5-meter reflectors of the Mount Wilson Observatory (USA, 1905 and 1917).
O. t. of the 2nd generation is also characterized by parabolic. Ch. mirror. Focuses - direct with corrector, Cassegrain and coude. The mirror is made of pyrex (glass with TCR reduced to 3 x 10 -6), relates. thickness 1/8. Very rarely the mirror was made lightweight, that is, it had voids on the back side. The pipe is lattice, the principle of compensation is implemented. Ball or hydrostatic bearings. Examples: 5-meter reflector of the Mount Palomar Observatory (USA, 1947) and 2.6-meter reflector of the Crimean Astrophysics. observatory (USSR, 1961).
O. t. 3rd generation began to be created at the end. 60s They are characterized by optical scheme with hyperbolic Ch. mirror (the so-called Ritchie-Chretien scheme). Focuses: direct with corrector, Cassegrain, coude. Mirror material - quartz or glass-ceramic (TKR 5 x 10 -7 or 1 x 10 -7), relative. thickness 1 / 8 . Compensation pipe scheme. Hydrostatic bearings. Example: 3.6-meter reflector of the European Southern Observatory (Chile, 1975).
O. t. 4th generation - instruments with a mirror dia. 7 - 10 m; They are expected to enter service in the 90s. They involve the use of a group of innovations aimed at meaning. reducing the weight of the tool. Mirrors are made of quartz, glass-ceramic and, possibly, pyrex (lightweight). Relates. thickness less than 1/10. Compensation pipe. The mount is azimuth. Hydrostatic bearings. Optical scheme - Ritchie - Chretien.
The world's largest telescope is the 6-meter telescope installed in the Special. astrophysics observatory (SAO) of the USSR Academy of Sciences in the North Caucasus. The telescope has a direct focus, two Nasmyth focuses and a coude focus. The mount is azimuth.
A certain perspective is available in O. t., consisting of several. mirrors, the light from which is collected in a common focus. One of these O. t. operates in the USA. It consists of six 1.8-meter parabolics. mirrors and the collecting area is equivalent to a 4.5-meter O. t. The mount is azimuthal.
Solar telescopes are characterized by very large spectral equipment, so the mirrors and spectrograph are usually made motionless, and the light of the Sun is applied to them by a system of mirrors called a coelostat. Diameter modern solar O. t. is usually 50 - 100 cm. Small highly specialized. solar instruments are made in the form of conventional refractors. It is planned to create a solar O. t. dia. 2.5 m.
Astrometric O. t. (intended to determine the positions of space objects) are usually small in size and higher. mechanical stability. O.t. for photography astrometry have special. lenticular lenses and equatorial mount. Passage instrument, meridian circle, photogr. anti-aircraft tube and a number of other astrometric. O. t. are not intended for tracking the daily movement of objects. Their equipment records the passage of an object through an optical lens. the axis of the instrument, the position of the cut relative to the meridian and vertical is known.
To eliminate the influence of the atmosphere, it is planned to install O. t. in space. devices.

A telescope is a unique optical instrument designed for observing celestial bodies. The use of instruments allows us to examine a variety of objects, not only those that are located close to us, but also those that are located thousands of light years from our planet. So what is a telescope and who invented it?

First inventor

Telescopic devices appeared in the seventeenth century. However, to this day there is debate about who invented the telescope first - Galileo or Lippershei. These disputes are related to the fact that both scientists were developing optical devices at approximately the same time.

In 1608, Lippershey developed glasses for the nobility to allow them to see distant objects up close. At this time, military negotiations were conducted. The army quickly appreciated the benefits of the development and suggested that Lippershey not assign copyright to the device, but modify it so that it could be looked at with both eyes. The scientist agreed.

The scientist’s new development could not be kept secret: information about it was published in local print media. Journalists of that time called the device a spotting scope. It used two lenses that allowed objects and objects to be magnified. Since 1609, trumpets with threefold magnification were sold in full swing in Paris. From this year, any information about Lippershey disappears from history, and information about another scientist and his new discoveries appears.

Around the same years, the Italian Galileo was engaged in grinding lenses. In 1609, he presented to society a new development - a telescope with threefold magnification. The Galileo telescope had higher image quality than the Lippershey telescope. It was the brainchild of the Italian scientist that received the name “telescope”.

In the seventeenth century, telescopes were made by Dutch scientists, but they had poor image quality. And only Galileo managed to develop a lens grinding technique that made it possible to clearly enlarge objects. He was able to obtain a twenty-fold increase, which was a real breakthrough in science in those days. Based on this, it is impossible to say who invented the telescope: if according to the official version, then it was Galileo who introduced the world to a device that he called a telescope, and if you look at the version of the development of an optical device for magnifying objects, then Lippershey was the first.

First observations of the sky

After the appearance of the first telescope, unique discoveries were made. Galileo used his development to track celestial bodies. He was the first to see and sketch lunar craters, spots on the Sun, and also examined the stars of the Milky Way and the satellites of Jupiter. Galileo's telescope made it possible to see the rings of Saturn. For your information, there is still a telescope in the world that works on the same principle as Galileo’s device. It is located at York Observatory. The device has a diameter of 102 centimeters and regularly serves scientists to track celestial bodies.

Modern telescopes

Over the centuries, scientists have constantly changed the design of telescopes, developed new models, and improved the magnification factor. As a result, it was possible to create small and large telescopes with different purposes.

Small ones are usually used for home observations of space objects, as well as for observing nearby cosmic bodies. Large devices make it possible to view and take photographs of celestial bodies located thousands of light years from Earth.

Types of telescopes

There are several types of telescopes:

1. Mirrored.
2. Lens.
3. Catadioptric.

Galilean refractors are considered lens refractors. Mirror devices include reflex devices. What is a catadioptric telescope? This is a unique modern development that combines a lens and a mirror device.

Lens telescopes

Telescopes play an important role in astronomy: they allow you to see comets, planets, stars and other space objects. One of the first developments were lens devices.

Every telescope has a lens. This is the main part of any device. It refracts light rays and collects them at a point called focus. It is in it that the image of the object is constructed. To view the picture, use an eyepiece.

The lens is placed so that the eyepiece and focus coincide. Modern models use movable eyepieces for convenient observation through a telescope. They help adjust the sharpness of the image.

All telescopes have aberration - distortion of the object in question. Lens telescopes have several distortions: chromatic (red and blue rays are distorted) and spherical aberration.

Mirror models

Mirror telescopes are called reflectors. A spherical mirror is installed on them, which collects the light beam and reflects it using a mirror onto the eyepiece. Chromatic aberration is not typical for mirror models, since light is not refracted. However, mirror instruments exhibit spherical aberration, which limits the field of view of the telescope.

Graphic telescopes use complex structures, mirrors with complex surfaces that differ from spherical ones.

Despite the complexity of the design, mirror models are easier to develop than lens counterparts. Therefore, this type is more common. The largest diameter of a mirror-type telescope is more than seventeen meters. In Russia, the largest device has a diameter of six meters. For many years it was considered the largest in the world.

Telescope characteristics

Many people buy optical devices for observing cosmic bodies. When choosing a device, it is important to know not only what a telescope is, but also what characteristics it has.

1. Increase. The focal length of the eyepiece and the object is the magnification factor of the telescope. If the focal length of the lens is two meters, and the eyepiece is five centimeters, then such a device will have a forty-fold magnification. If the eyepiece is replaced, the magnification will be different.
2. Permission. As you know, light is characterized by refraction and diffraction. Ideally, any image of a star looks like a disk with several concentric rings called diffraction rings. The disk sizes are limited only by the capabilities of the telescope.

Telescopes without eyes

What is a telescope without an eye, what is it used for? As you know, each person’s eyes perceive images differently. One eye can see more and the other can see less. So that scientists can see everything they need to see, they use telescopes without eyes. These devices transmit the image to monitor screens, through which everyone sees the image exactly as it is, without distortion. For small telescopes, cameras have been developed for this purpose that are connected to devices and photograph the sky.

The most modern methods of seeing space are the use of CCD cameras. These are special light-sensitive microcircuits that collect information from the telescope and transmit it to the computer. The data obtained from them is so clear that it is impossible to imagine what other devices could obtain such information. After all, the human eye cannot distinguish all shades with such high clarity as modern cameras do.

To measure the distances between stars and other objects, special instruments are used - spectrographs. They are connected to telescopes.

A modern astronomical telescope is not one device, but several at once. The received data from several devices is processed and displayed on monitors in the form of images. Moreover, after processing, scientists obtain very high-definition images. It is impossible to see such clear images of space with your eyes through a telescope.

Radio telescopes

Astronomers use huge radio telescopes for their scientific research. Most often they look like huge metal bowls with a parabolic shape. Antennas collect the received signal and process the resulting information into images. Radio telescopes can only receive one wavelength of signals.

Infrared models

A striking example of an infrared telescope is the Hubble apparatus, although it can also be optical. In many ways, the design of infrared telescopes is similar to the design of optical mirror models. Heat rays are reflected by a conventional telescopic lens and focused at one point where the heat-measuring device is located. The resulting heat rays are passed through thermal filters. Only after this does photography take place.

Ultraviolet telescopes

When photographing, film can be exposed to ultraviolet rays. In some parts of the ultraviolet range it is possible to receive images without processing or exposure. And in some cases it is necessary for the light rays to pass through a special structure - a filter. Their use helps highlight the radiation of certain areas.

There are other types of telescopes, each of which has its own purpose and special characteristics. These are models such as X-ray and gamma-ray telescopes. According to their purpose, all existing models can be divided into amateur and professional. And this is not the entire classification of devices for tracking celestial bodies.

Telescope structure

In the 20th century, astronomy made many steps in studying our Universe, but these steps would have been impossible without the use of such complex instruments as telescopes, the history of which goes back hundreds of years. The evolution of the telescope took place in several stages, and I will try to talk about them.

Since ancient times, humanity has been yearning to find out what is there in the sky, beyond the Earth and invisible to the human eye. The greatest scientists of antiquity, such as Leonardo da Vinci, Galileo Galilei, attempted to create a device that would allow one to look into the depths of space and lift the veil of mystery of the Universe. Since then, many discoveries have occurred in the field of astronomy and astrophysics. Every person knows what a telescope is, but not everyone knows how long ago and by whom the first telescope was invented, and how it was designed.

A telescope is a device designed to observe celestial bodies.

In particular, a telescope refers to an optical telescopic system not necessarily used for astronomical purposes.

There are telescopes for all ranges of the electromagnetic spectrum:

b optical telescopes

b radio telescopes

b x-ray telescopes

gamma-ray telescopes

Optical telescopes

A telescope is a tube (solid, frame or truss) mounted on a mount equipped with axes for pointing at and tracking an object of observation. A visual telescope has a lens and an eyepiece. The rear focal plane of the lens is aligned with the front focal plane of the eyepiece. Instead of an eyepiece, photographic film or a matrix radiation receiver can be placed in the focal plane of the lens. In this case, the telescope lens, from an optical point of view, is a photographic lens. The telescope is focused using a focuser (focused device). telescope space astronomy

According to their optical design, most telescopes are divided into:

b Lens (refractors or diopter) - a lens or lens system is used as a lens.

b Mirror (reflector or catoptric) - a concave mirror is used as a lens.

b Mirror-lens telescopes (catadioptric) - a spherical mirror is used as a lens, and a lens, lens system or meniscus serves to compensate for aberrations.

Typically, when you buy a telescope, you get simple but necessary accessories without which it cannot function: eyepieces, a Barlow lens, a wrapping prism or diagonal mirror and a finder. Typically, most amateur telescopes are equipped with such accessories.

But everything can always be done only with complete accessories, or not all necessary accessories are included in the kit. As a rule, expensive telescope models are equipped with only one eyepiece and require the purchase of the necessary set.

Eyepieces

An eyepiece is an element of the optical system necessary to change magnification. It is impossible to observe through a telescope without an eyepiece. To calculate the magnification of a telescope, you need to divide the focal length of the telescope by the focal length of the eyepiece. For example, the focal length of the telescope is 700 mm, and the focal length of the eyepiece is 10 mm, in this case, the magnification will be 70 times.

Eyepieces come in different classes and optical designs. Eyepieces can vary in viewing angle, and can be divided into simple, wide-angle and ultra-wide-angle. Also, a zoom eyepiece with variable focal length and magnification is very convenient.

Adjustment eyepieces and laser collimators will be useful to owners of mirror telescopes, because... Such telescopes require re-adjustment after almost every transportation. Only in this case will the reflecting telescope use its potential

When choosing an eyepiece, pay attention to the mounting diameter; it must match the mounting diameter of the focuser. Standard sizes: 0.96", 1.25", 2".

Barlow lenses

A Barlow lens is another popular telescope accessory. A Barlow lens is a diverging lens or several lenses that increases the focal length of the telescope several times, and accordingly, allows you to make the magnification of the telescope several times greater.

The Barlow lens is used only in conjunction with the eyepiece; the Barlow lens cannot be used separately.

Light filters

A light filter is also an important, and sometimes even necessary, accessory for observing through a telescope. Light filters for telescopes can be divided into several types: solar filters, color planetary filters, narrow-band filters for observing and photographing nebulae.

Solar filters are used to safely observe the solar disk. Under no circumstances do we recommend observing the Sun through a telescope that is not equipped with a special filter. By using special filters such as Seymour Solar and Baader AstroSolar, observations of the Sun become absolutely safe, because... solar filters cut off 99.999% of visible radiation from the sun. To observe the Sun safely, you must place a solar filter on the telescope lens. That is, the inner diameter of the solar filter must be equal to the outer diameter of the telescope tube. It is not safe to observe through an ocular solar filter as the sun's rays cause heat and can cause the filter to crack! Observing the Sun can cause heating and damage to the filter placed on the eyepiece.

The most budget-friendly option for a solar filter is to make a filter according to the diameter of the telescope using a special solar film. This film is also completely safe and provides a rich contrast image. Depending on the film manufacturer, the color of the solar disk when observed may vary (Seymour Solar – bright orange, Bader AstroSolar – white). Also, there is a difference between visual and photographic film. Suitable for safe visual observations only visual film.

Another option is ready-made glass solar filters, designed for a specific diameter of the telescope tube.

Color filters are used mainly for visual observations of planets. Such filters make the image of planets more contrast and highlight details on their surface. Color filters include a lunar filter of neutral gray or green color, which dims the brightness of the Moon, making observations more comfortable. Color filters are sold individually or in sets.

Colored filters for observing planets

Color filters They are 1.25" and 2" in diameter, threaded, and screw into the eyepiece barrel.

The red filter is used for daytime observations of Venus, observations of the polar caps on the surface of Mars, and blue clouds on Jupiter. The orange filter will be very useful for observing the Moon, for daytime observations of Mercury, detailing the details of the surface of Mars, belts, festoons on Jupiter. Yellow filter - enhances the contrast of the surface of Venus, enhances the visibility of seas and clouds on Mars, belts on Jupiter. Green – increases the contrast of details on the Moon, improves the contrast of details on Venus, useful for observing storms and the polar caps of Mars. Blue-blue - very useful for

Special narrow-band filters are filters that cut off certain regions of wavelengths, leaving a narrow bandwidth of radiation? making the image more contrast. Such filters are used both for visual observations and for astrophotography of deep space objects emitting in a certain spectrum.

In our store you can buy ready-made sets of accessories for telescopes.

In addition to the accessories listed, you may also need the following accessories:

• T2 adapter ring for shooting through a telescope at direct focus
• Special astronomical camera
• Smartphone holder for photographing through the eyepiece phone for photographing through the eyepiece
• Telescope case
• Laser collimator for telescope alignment
• Other accessories