How Do I Build a Telescope?

A telescope is an optical instrument that uses lenses or mirrors and other optical devices to observe distant objects. The light is refracted through the lens or reflected by the concave mirror to make it enter the small hole and converge to form an image. Then it is seen through a magnifying eyepiece. Also known as "Senior Mirror".

[wàng yun jìng]

Telescope is a

Optician Middelburg, 1608

Hubble Space Telescope

1.Magnification

General eyepiece

English alphabet model

The English alphabet models sometimes have different meanings in different telescope lens brands. Generally, it is easy to identify the following:

(1) CF: central focus

(2) ZCF: traditional Polo prism left and right expansion type, center focus

(3) ZWCF: One "Super Wide Angle" (W) than item (2)

(4) CR: camouflage rubber case

(5) BR: Black rubber shockproof case

(6) BCF: black, center focus

(7) BCR: black camouflage rubber case

(8) IR: Lightweight aluminum alloy case

(9) IF: Individual focus adjustment for left and right eyes

(10) WP: Internal charge

To celebrate the "International Year of Astronomy 2009", the British "New Scientist" selected the most famous telescope in human history. Here are the 14 most famous telescopes:

Galileo refracting telescope

Galileo was the first to recognize that the telescope might be used for astronomical research. Although Galileo did not invent the telescope, he improved the previous design and gradually increased its magnification. The scene in the picture took place in August 1609, and Galileo was demonstrating his telescope to the then Venetian ruler. Galileo built a telescope with a diameter of 4.2 cm and a length of about 1.2 meters. He uses a plano-convex lens as the objective lens and a concave lens as the eyepiece. This optical system is called a Galilean telescope. Galileo pointed the sky with this telescope and made a series of important discoveries. Astronomy has entered the telescope era. The advantages of refracting telescopes are long focal lengths, large negative scales, and insensitivity to lens barrel bending, which is most suitable for astronomical work. However, it always has residual chromatic aberration, and at the same time, it absorbs radiation in the ultraviolet and infrared bands very well.

Newton's reflection telescope

Newtonian telescopes do not use glass lenses to refract light or

Hubble Space Telescope

Bend, but use a curved mirror to reflect light above a focal point. This method is several times higher than using a lens to magnify an object. After Newton failed to grind aspheric lenses many times, he decided to use a spherical mirror as the main mirror. He used 2.5 cm diameter metal to grind a concave mirror, and placed a reflector at a 45o angle to the main mirror in front of the focal point of the main mirror, so that the convergent light from the main mirror's telescope passed through the mirror. After reflecting the lens barrel at a 90o angle, it reaches the eyepiece. The main advantage of reflecting telescopes is that there is no chromatic aberration. When the objective lens is parabolic, it can also eliminate the replica of Newton's first reflecting telescope shown in the spherical aberration diagram.

Herschel telescope

In the late 18th century, German musician and astronomer William Herschel began manufacturing large reflective telescopes. The picture shows the largest telescope made by Herschel, with a mirror diameter of 1.2 meters. The telescope is very bulky and requires four people to operate it. Herschel was a master of making reflective telescopes. He was a musician in his early years. He loved astronomy and began to make telescopes in 1773. He made hundreds of telescopes in his lifetime. The telescope made by Herschel placed the objective lens obliquely in the lens barrel, which reflected the parallel light and focused on one side of the lens barrel. After the invention of the reflective telescope, reflective materials have been an obstacle to its development: the bronze used for casting mirrors is easy to corrode, and it has to be polished regularly, which requires a lot of financial resources and time. Metals with good corrosion resistance are denser and very dense than bronze. expensive.

4.Yekis refracting telescope

The Yakis refracting telescope is located at the Yakis Observatory in Wisconsin, USA. The main lens was completed in 1895, which was the largest telescope in the world at that time. At the end of the 19th century, with the improvement of manufacturing technology, it became possible to manufacture larger-diameter refracting telescopes, and a climax of manufacturing large-diameter refracting telescopes followed. Seven of the eight refracting telescopes above 70 cm in the world were built between 1885 and 1897, the most representative of which were the Yekesi telescope with a diameter of 102 cm and the construction in 1886. 91 cm Rick telescope. However, the development of refracting telescopes was limited later, mainly because it was technically impossible to cast a large piece of perfect glass as a lens, and the deformation of large-sized lenses was very obvious due to gravity, thus losing sharp focus.

5.Mount Wilson 60-inch telescope

This picture was taken in 1946 when night operator Gein Hancock was manually manipulating the telescope. In 1908, American astronomer George Ellery-Hale built a 60-inch reflecting telescope and installed it on Mount Wilson. This was the world's largest telescope at the time, and its astronomy fields such as spectral analysis, parallax measurement, nebula observation, and photometry became world-leading equipment. Although the caliber of the Hooker telescope surpassed it a few years later, it remained one of the largest telescopes in the world for several years thereafter. An early adaptive optics facility was installed on the Hale telescope in 1992, increasing its resolution from 0.5-1.0 arc seconds to 0.07 arc seconds.

6, Hook 100-inch telescope

Under the auspices of rich businessman John Hook, a 100-inch reflecting telescope was built at the Mount Wilson Observatory in 1917. For the next 30 years, it has been the largest telescope in the world. To provide smooth operation, liquid mercury is used in the telescope's hydraulic system. In 1919, Albert Michelson installed a special device for the telescope: an interferometer. This was the first time that optical interference devices were used in astronomy. Michelson can use this instrument to accurately measure the size and distance of stars. Henry Norris Russell used data from the Hook Telescope to develop his classification of stars. Edwin Hubble used his 100-inch telescope to complete his key calculations. He determined that many of the so-called "nebulae" were actually galaxies outside the Milky Way. With the help of Milton-Hermasson, he realized that the galaxy's red shift indicates that the universe is expanding.

7, Helle 200-inch telescope

Hale was not very happy with the Hooker 100-inch telescope. In 1928, he decided to set up another giant 200-inch reflecting telescope at the Paloma Observatory. The new telescope was completed and put into use in 1948. Hale graduated from the Massachusetts Institute of Technology in 1890. In 1892, he was an associate professor of astrophysics at the University of Chicago, and began to organize the Ye Kaishi Observatory as the director. In 1904, the Mount Wilson Solar Observatory was established, which was later the Mount Wilson Observatory. He served as the first director until he retired from illness in 1923. In 1895, Hale founded the Journal of Astrophysics. In 1899 he was elected vice president of the newly formed American Astronomy and Astrophysics Society. The major contributions of Hale's life are reflected in two aspects: the observation and research of the sun and the manufacture of giant telescopes.

8. Horn Antenna

The horn antenna is located at the Bell Telephone Experimental Research Institute in New Jersey, USA, and was used to detect and discover cosmic microwave background radiation. The horn antenna was built in 1959. When the length of the horn is constant, if the opening angle of the horn is gradually increased, the phase difference between the mouth surface and the quadratic phase is also increased at the same time, but the gain does not increase in synchronization with the mouth surface size, and there is a Mouth size, a speaker with this size is called the best speaker. The radiation field of the horn antenna can be calculated from the mouth-to-surface field using Huygens principle. The mouth-to-surface field is determined by the mouth size and the propagation pattern of the horn. Geometric diffraction theory can be used to calculate the effect of the horn wall on the radiation, so that the calculated pattern and the measured value can agree well up to the far side lobe.

9.Very large array radio telescope

The Very Large Array Radio Telescope is located in Socorro, New Mexico, USA, and was completed and put into use in 1980. Very large arrays consist of 27 parabolic antennas with a diameter of 25 meters, arranged in a Y-shape. Astronomers can use very large arrays to study various phenomena in the universe such as black holes and nebulae. Very large telescopes are a group of optical telescope arrays. It includes four 8.2-meter telescopes, each in the array is a large telescope, and each can work independently, and has the ability to capture light 4 billion times weaker than that observed by the human eye, which is larger than the South African large telescope The weakest light that can be captured is four times weaker. Very large array telescopes can aggregate up to 3 telescopes together to form independent units. The light is combined into a unified beam through underground lenses, which enables the telescope system to observe images 25 times higher than a single telescope.

10.The Hubble Space Telescope

The Hubble Space Telescope was launched in April 1990. It lies above the Earth's atmosphere, so it has achieved a revolutionary breakthrough never before achieved by any other ground-based telescope. Astronomers use it to measure the expansion ratio of the universe and the dark energy and mysterious forces that produce this expansion. The Hubble Space Telescope has reached "old age." It has undergone several overhauls during its more than ten years in space. Although after each overhaul, "Hubble" has a new look, especially in 2001 when scientists used the Columbia Space Shuttle to carry out the fourth overhaul, installing mapping cameras for it, replacing solar panels, and replacing 11 years of work. Power control device, and activated the near-infrared camera and multi-target spectrometer in the "sleep" state, however, the overhaul still can't conceal its old state, because "Hubble" has been "working with illness" since the beginning of space status.

11.Keck series telescope

The Keck telescope is located in Mauna Kea, Hawaii, and has a diameter of 10 meters. Because it is impossible for today's technology to achieve a monocular telescope mirror diameter of more than 8.4 meters, the mirror of the Keck telescope is composed of 36 hexagonal segments. The large mirror of the Kaine telescope makes it unusual to use, not only because of its large size, but also because it consists of 36 small hexagonal lenses with a diameter of 1.8 meters. The Keck telescope has ushered in a new era of ground-based telescopes. It is twice the size of the Hellenic Telescope on Mount Paloma, California, which was the largest telescope in the world for decades. Someone once thought that it was impossible to make such a large telescope, but new science and technology have made the impossible a reality.

12.Sloan 2.5-meter telescope

The Sloan Digital Sky Survey's 2.5-meter telescope is located at the Cape Arbor Observatory in New Mexico, USA. The telescope has a rather complex digital camera with 30 charge-coupled device (CCD) detectors inside. The Sloan Telescope uses a wide field of view telescope with a diameter of 2.5 meters. The metering system is equipped with five filters located in the u, g, r, i, and z bands to photograph celestial bodies. These photos are processed to generate a list of celestial bodies, including various parameters of the observed celestial bodies, such as whether they are point-like or extended. If it is the latter, the celestial body may be a galaxy and their brightness on the CCD. , Which is related to its magnitude in different bands. In addition, astronomers have selected targets for spectral observations.

13. Wilkinson cosmic microwave anisotropy detection satellite

NASA launched the Wilkinson Cosmic Microwave Anisotropy Detection Satellite (WMAP) in July 2001 to study the radiation background of the cosmic microwave background and the remnants of the Big Bang. WMAP created the first clear picture of the cosmic microwave background, so that the age of the universe can be accurately determined to be 13.7 billion years. The goal of WMAP is to find small differences between the temperatures of the cosmic microwave background radiation to help test theories about the universe. It is the successor of COBE and is one of the intermediate explorer satellite series. WMAP is named after David Wilkinson, the forerunner of cosmic background radiation.

14, Swift observation satellite

The Swift observation satellite was launched in 2004 and is mainly used to study the phenomenon of gamma storms. "Yuyan" can automatically observe the phenomenon of gamma storm in just one minute. So far, it has discovered hundreds of gamma bursts. The "Swift" satellite is actually an international multi-band observatory dedicated to determining the origin of gamma-ray bursts and exploring the early universe. It is mainly composed of three parts, studying the gamma-ray burst and its flares from four aspects, namely, gamma rays, X-rays, ultraviolet rays and light waves. During many years of operation, the Swift satellite has captured a total of 10 gamma-ray bursts operating at extremely fast angular speeds. The shortest gamma-ray burst lasted only 50 milliseconds. The Yuyan satellite can detect individual star parameters beyond 12 billion light years.

October 13th, 2008, Beijing time. The US MSNBC website announced eight great space telescopes until 2008. These telescopes that have entered space in the past 20 years are like "eyes of space", helping humans have a clearer understanding of the universe Recognition. Here are these eight space telescopes. ^[3]

15. Kepler space telescope ^[3]

The Kepler Mission is a space telescope designed by NASA to discover terrestrial planets like other stars. Using the space photometer developed by NASA, it is estimated that it will take 3.5 years to observe the luminosity of 100,000 stars in the orbit around the sun, and detect whether there is a planet transit phenomenon (the planet is detected by the transit method). To honor the German astronomer Johannes Kepler, the mission is called Kepler Space Telescope. Kepler is a scientific mission focused on NASA's low-cost discovery program. NASA's Ames Research Center is the authority in charge of this task, providing the main researchers and responsible for the development of ground systems, the execution of tasks, and the analysis of scientific data.

After months of hard work, NASA announced on August 15, 2013 that it had abandoned the repair of the Kepler space telescope. Kepler has thus ended its main mission of searching for exoplanets in the solar system, but it may still be used for other scientific research.

Hubble Space Telescope

Hubble Space Telescope

Launch time: 1990

The Hubble Telescope was launched in 1990. Over the past 20 years, this remarkable telescope has changed our understanding of the universe and dedicated a large number of wonderful photos of space to the public. However, the Hubble Telescope suffered a hardware failure that prevented it from communicating with the ground. But NASA is working on a plan to revive the Great Observatory, bringing the Hubble telescope into service at least until 2013.

Compton Gamma Ray Space Telescope

Launch time: 1991

Main function: Finding high-energy gamma rays

Some of the most violent events in the universe are invisible to the naked eye. They occur in a spectral environment called gamma rays. Gamma rays are the most powerful photons in the electromagnetic spectrum. The Compton Gamma-ray Space Telescope weighs 17 tons and was launched in 1991 by the space shuttle Atlantis to observe high-energy rays in the universe. The advanced instruments carried by Compton revealed to the world the distribution of high-energy gamma-ray bursts, enabling scientists to draw wonderful maps such as the one above, which shows gamma-ray bursts focused along the galactic plane . In 2000, after a gyroscope failure, Compton was safely out of orbit.

3.Chandra X-ray Space Telescope

Launch time: 1999

Main function: Observe black holes and supernova

For a long time, science fiction writers like to give X-ray-like vision to fictional superheroes such as Superman. This super power can make them see things that ordinary people cannot see. After the Chandra X-ray Space Telescope was launched in 1999, real-world astronomy possessed this superpower. The Chandra Telescope is used to observe objects such as black holes and supernovae in the form of high-energy light. Its 340-year-old supernova remnant "Cassiopeia A" revealed to astronomers that such an exploding star may be an important source of cosmic rays. Cosmic rays are high-energy particles that constantly bombard the earth.

4.XMM-Newton X-ray Space Telescope

Launch time: 1999

Main function: uninterrupted observation of deep space

In December 1999, the multi-lens X-ray observation satellite (now called XMM-Newton) was launched, and European astronomers have since owned their own X-ray observation stations. The satellite is equipped with three X-ray telescopes, known for its bizarre telescope flight orbits, which allow it to observe deep space for long periods of time. XMM-Newton has made many breakthroughs in the European astronomy community, such as the observation of the largest cluster of galaxies ever seen in the distant universe. This massive cluster of galaxies (on the right in the picture above) proves the existence of a mysterious power called dark energy. It is said that dark energy has accelerated the expansion of the universe. Scientists say that such huge galaxy clusters may have formed in the early universe.

5. Wilkinson microwave anisotropy detector

Launch time: 2001

Main function: detect the structure of the early universe

About 380,000 years after the Big Bang, the universe released a lot of radiant heat, which is called cosmic microwave background radiation. According to astronomical theory, the universe originated from the Big Bang. NASA launched a spacecraft in 1992 to detect small changes in cosmic microwave background radiation. The Wilkinson microwave anisotropy detector was launched in 2001. For many years, it has been studying more subtle changes in the background radiation of the cosmic microwave, giving scientists a preliminary understanding of the state of the universe after the Big Bang. As shown above, NASA published an early universe map based on Wilkinson microwave anisotropy detector data in 2003. These data confirm that the universe has a history of 13.7 billion years.

6.Spitzer Space Telescope

Spitzer Space Telescope

Launch time: 2003

Main function: Penetrating interstellar gas and dust

I don't know if you have ever climbed to the top of the mountain and only saw the smoke-filled scene. The impenetrable interstellar gas and dust pose similar problems for astronomers trying to understand distant stars and galaxies. The Spitzer Space Telescope (pictured right), launched in 2003, solved this problem for astronomers by collecting infrared light. Infrared light is an invisible mode of electromagnetic radiation related to a certain amount of heat, which cannot be blocked by gas clouds. Through the cameras carried by the Spitzer Space Telescope, astronomers have conducted unprecedented surveys of galaxies, newly formed planetary systems, and areas that form stars (such as the area W5 on the left).

7.Fermi gamma-ray space telescope

Launch time: 2008

Main function: study black holes and unveil the mystery of dark matter

Black holes are called whirlpools in space and draw everything around them. But when black holes devour stars, they also spew outwards at speeds near the speed of light, releasing gamma-ray gas. Why does this happen? The Fermi Gamma-ray Space Telescope launched in July 2008 may unravel this mystery. The goal of this telescope is to study high-energy radiation, and it may also unravel the mystery of dark matter, which will help further understand the most mysterious in the universe Unheard of substances in extreme environments. Dark matter is the source of gamma-ray bursts.

8.The James Webb Space Telescope

James Webb Space Telescope

Launch time: 2013

Main function: find the earliest stars and galaxies formed in the universe

Launched in 2013, the James Webb Space Telescope will use its light-gathering power seven times that of the Hubble Space Telescope to explore space. The James Webb Space Telescope is regarded as Hubble's "successor", and its huge light-gathering ability may enable it to observe the earliest stars and galaxies formed in the universe. The core part of the James Webb telescope is an 18-sided hexagonal mirror, which will act together to focus on objects in the distant, young universe. Recent research findings may provide clues on everything from star, galaxy, planet formation to solar system evolution.

The size of the telescope is mainly measured by the diameter of the telescope. In order to make more careful research and observation of celestial bodies, and to find fainter celestial bodies, people have been working hard to increase the caliber of telescopes for many years. However, different calibers have different requirements for different telescopes. The world's largest reflecting telescope is a 6-meter telescope built in the Soviet Union in 1975. It has surpassed the 5-meter reflecting telescope at the Palomar Observatory in the United States for more than 30 years. The total weight of its rotating parts is 800 tons, which is also 200 tons heavier than the United States. In 1978, a combined multi-mirror telescope with a diameter of 4.5 meters was put into trial operation in the United States. The telescope consists of six identical Cassegrain telescopes, each with a diameter of 1.8 meters. Six telescopes are arranged in a hexagon around the central axis, and each of the six converging beams is directed to a six-sided beam combiner through a plane mirror, and then the six beams are focused on a common focus. The advantages of the multi-mirror telescope are: large aperture, Short tube, small footprint, low cost. The largest optical telescope at present is the 10-meter Keck telescope.

The largest refracting telescope in the world today is the Schmidt telescope installed at the German Observatory in Taudenburg, Germany, with a corrected diameter of 1.35 meters and a main mirror diameter of 2 meters. The German refraction mirror also surpassed the largest Schmidt telescope in the United States. The two "world's best" on the telescope were successively taken away.

On October 11, 1957, the world's largest radio telescope was built on the banks of the Yodrell River in the United Kingdom. It was completed earlier than originally planned to track the first Soviet satellite launched the previous week.

The world's earliest telescope was made by Italian scientist Galileo in 1609. Therefore, it is also called Galileo telescope. This is a refracting telescope. He used a convex lens crop lens and a concave lens as the eyepiece, so he observed the positive image. Speaking of the first telescope in the world, Galileo said: "Thanks for having a telescope, we have been able to make the celestial body thirty to forty times closer to us than Aristotle, so we can distinguish many things on the celestial body, All Aristotle hasn't seen; apart from that, these solar system sunspots are absolutely invisible to him. So we want Biaristodu to be more confident in treating celestial bodies and the sun. "