What is Astronomy?

Astronomy is a discipline that studies the structure and development of celestial bodies and the universe. The content includes the structure, nature and operating laws of celestial bodies. Astronomy is an ancient science. Since the history of human civilization, astronomy has played an important role.

Mainly by observing the radiation emitted by celestial bodies to the earth, discovering and measuring their positions, exploring their movement laws, studying their physical properties, chemical composition, internal structure, energy sources and their evolution laws. ^[1]

In the long history of astronomy, with the improvement and development of research methods, astrometry, astromechanics, and astrophysics have been established.

Chinese name: astronomy
Foreign name: Astronomy
Category: Science (Natural Science)

research direction: Space objects, structures and development
Subject branch: Theoretical Astronomy and Observation Astronomy
Open a college: Nanjing University, Beijing Normal University, etc.

Significance of astronomy research

astronomy The study of astronomy has great practical significance for our lives and has a great impact on human's natural outlook. Ancient astronomers determined the time, direction, and calendar by observing the sun, moon, and other celestial bodies and celestial phenomena. This is also the beginning of astrometry. If humans observe celestial bodies and record astronomical phenomena, the history of astronomy is at least five or six thousand years old. Astronomy plays a very important role in the early history of human civilization. The pyramids of Egypt and Stonehenge in Europe are well-known prehistoric astronomical sites. Copernicus' heliocentric theory liberated natural science from theology; Kant and Laplace's Nebula about the origin of the solar system opened the first gap in the metaphysical view of nature in the eighteenth century.

The emergence of Newtonian mechanics, the discovery of nuclear energy, and other events that have played an important role in human civilization are closely related to astronomical research. At present, research on high-energy astrophysics, compact stars and the evolution of the universe can greatly promote the development of modern science. The study of solar and solar system objects, including the earth and satellites, has many applications in aerospace, geodesy, communication and navigation sectors. Astronomy originated from the seasonal acquisition and divination of ancient humans.

Astronomy follows the development path of observation-theory-observation, and continuously extends human vision to a new depth in the universe. With the development of human society, the research object of astronomy has developed from the solar system to the entire universe. Today, astronomy has been classified into three major disciplines: astrometry, astromechanics, and astrophysics. Classification by observation methods has formed several branches of optical astronomy, radio astronomy and space astronomy. ^[2]

Objects of astronomy research

With the development of astronomy, the detection range of humans has reached the distance of about 10 billion light years from the earth by the visual observation of the sun, moon, and stars in the sky. According to scale and scale, the research objects of astronomy can be divided into: ^[2]

Astronomical planet level

Including planets in the planetary system, satellites orbiting the planet and a large number of small celestial bodies, such as asteroids, comets, meteors, and interplanetary matter. Stellar system. ^[2]

Astronomy stellar hierarchy

At present, hundreds of millions of stars have been observed, and the sun is just one of the countless stars.

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Astronomical galaxy level

The solar system in which human beings are located is only a stack of galaxies made up of countless stars. The Milky Way is just an ordinary galaxy. In addition to the Milky Way, there are many extragalactic galaxies. The galaxy further constitutes a larger celestial system, galaxy group, galaxy cluster and super galaxy cluster. ^[2]

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Astronomical Universe

Some astronomers have proposed total galaxies one level higher than super galaxy clusters. According to current understanding, the total galaxy is the range of the universe that humans can observe at present, with a radius of more than 10 billion light years.

One of the hottest and most convincing topics in astronomy research is the study of the origin and evolution of the universe. The theories of the origin of the universe have emerged endlessly. Among them, the most representative and most influential, and the most supported is the Big Bang theory proposed by American scientist Gamow and others in 1948. According to this theory, which was being perfected, the universe was born in a violent explosion about 13.7 billion years ago. Then the universe keeps expanding, the temperature keeps falling, and various elementary particles are produced. As the temperature of the universe further decreases, the material begins to collapse due to gravitational forces, gradually forming clusters. Galaxies began to form about 10 years in the universe and gradually evolved into what they are today.

Astronomy research methods

The object of astronomy research is extremely large scale, extremely long time, extreme physical characteristics, so it is difficult for the ground laboratory to simulate. Therefore, the research methods of astronomy mainly rely on observation. Because the atmosphere of the earth is opaque to ultraviolet radiation, X-rays, and gamma rays, many methods and means of space exploration have emerged, such as balloons, rockets, satellites, and spacecraft.

Astronomical theories are often due to lack of observational information, astronomers often come up with many hypotheses to explain some astronomical phenomena. Then based on the new observations, modify the original theory or replace it with a new theory. This is where astronomy differs from many other natural sciences. ^[2]

Astronomy Difference Analysis

Astro student Shaw

The birth of the zodiac sign has an astronomical background.

In the primitive era, the ancestors experienced the cycle of alternating cold and heat. Song Hao's Song Mo Ji Wen recorded: "The Jurchen is extremely old, so far as Zheng Shuo, and its people do not know the age. When asked, it says," I see the grass a few times, "and the grass is one year old." Song Dynasty Meng Xun's "Record of Meng Xuan" also said: "It's one year old for every grass, and some people ask him how old it is," said another observer who found that the moon's profit and loss cycle can be used to measure the age. The length of the twelve moons was found to be one year old. This discovery is one of the most accurate results of the early calendar. "Twelve" is regarded as the "large number of heavens" that conveys the will of God. Tiangan needs the Earthly Branch as a companion. The sun and the moon are opposite, while the sky and the earth are opposite.

Astronomy Ancient Egypt

They developed their own calendar. Marx said: "The need to calculate the period of the Nile's water fluctuations has produced astronomy in Egypt." That is to say, the production of astronomical knowledge comes from observation of nature. The ancient Egyptians found that the rising of the Nile River in the delta occurred simultaneously with the rise of the sun and Sirius on the horizon. They set the time between the two occurrences as one year, a total of 365 days. The whole year is divided into 12 months, 30 days a month, and the remaining 5 days are used for festivals. At the same time, the year is divided into 3 seasons, namely "flooding season", "growing season", and "harvest season". 4 months per season. Herodotus said: "The Egyptians were the first of the human beings to come up with a method of counting the solar year .... In my opinion, their timing method is better than that of the Greeks. Because the Greeks, every time Every other year, we must insert a leap month to make the seasons coincide ... "

The Egyptians divided the day and night into 12 parts, each of which was 1/12 of the time from sunrise to sunset or sunset to sunrise. The Egyptians used a stone bowl to measure time. There was a small opening at the bottom of the stone bowl, and water droplets leaked out of the bowl at a fixed rate. The stone bowl is marked with various signs to mark the hours in different seasons. Don't doubt, the astrology of ancient Egypt was very developed. Just like the characteristics of ancient Egyptian civilization, their twelve constellations are also represented by ancient Egyptian gods.

The ancient Egyptians' research and accumulation of knowledge originated from the needs of agricultural production in ancient times. The agricultural production of ancient Egypt, due to the sowing season and the harvest of fields and orchards, depended on the annual flood of the Nile, and the flood of the Nile was related to the astral movement, especially the sunrise and Sirius rise every 1460 Air and Nile flooding occur simultaneously. So, monks started making celestial maps very early. Egypt's astronomy, like mathematics, is still at a low level of development and lags behind Babylon.

In the ancient Egyptian literature, there is neither a description of mathematical instruments, nor any observations of eclipses, eclipses, or other celestial phenomena. The Egyptians used to think of planets as roamers, and named named stars and constellations (it is rarely equivalent to modern ones). Therefore, their only creation can be exaggerated as the name of "astronomy".

Some inscriptions preserved from the time of the Old Kingdom to the later Ptolemy include a list of the divisions of the sky. What the Greeks called "Dekan" (tenths of the zodiac) is the so-called 12-hour nighttime pictured. People use Dekan to divide the year. A year consists of 36 consecutive days of 10 days. The 36 Dekans total 360 days, making up a year. However, five days are still missing, so every few years, every week Dekan must be moved backwards. The Egyptians' concept of the universe was often explained by different myths, and some paintings of different celestial bodies were retained.

In the picture in the tomb of the New Kingdom era, we see the sky goddess Nute in the image of Tianniu. Her body is bent over the earth to form a dome of the heavenly palace. The abdomen is the sky and decorated with the so-called "star belt" . There are two solar boats in front of and behind the star belt. One of them bears the sun god pull. He cruises in the sky by day and evening boat. The god of the atmosphere stands under the belly of the ox, and raises his hands to support the ox, the sky. There are 2 gods supporting each of the limbs of the Celestial Beef. According to another myth, the goddess of the sky, Nut, and the god of the earth, Gebo, embraced together. His father, the god of the atmosphere, supported the goddess with his hands and separated it from Gabe, only to let the goddess of Nut His feet and fingers were in contact with the ground, while Gaber was half-lying on the ground. These myths and legends reflect the Egyptians' vague concepts of heaven, earth, and stars.

Certain monks in Egypt were designated as "time recorders". They monitor the movement of stars at night every day. They need to record the order of fixed stars, the movement of the moon and planets, the rise and fall time of the moon and sun, and the orbits of various celestial bodies. These people also collated the above information and submitted reports on changes in celestial bodies and their activities. A map of different time divisions of the stars is kept in the tombs of Ramesses VI, VII, and IX. It consists of 24 tables, and one table is used as a half-month interval. Along with each table, there is a description of the constellation diagram. The astronomical map in the tomb of Senemut during the 18th dynasty's Hite Sipusout rule can be said to be the earliest astronomical map known to date.

A group of stars known to temple astronomers is "Ikem Secu," or "stars that never disappear." Obviously North Star. The second group is "Ikem Veredu", that is, "the star that never stops", which is actually a planet. Whether the Egyptians knew the difference between planets and stars has not been reported. The stars they know are Sirius, Orion, Ursa Major, Cygnus, Cassiopeia, Draco, Scorpio, Aries, etc. The planets they noticed were Jupiter, Saturn, Mars, Venus, etc. Of course, their astrological knowledge is imprecise, and stars and constellations rarely equate with modern understanding. The worship of the sun occupies an important position in Egypt. Since the pre-dynasty era, the sun has been portrayed as a scarab and has a prominent place in Egyptian religion. Moreover, the sun has different names at different times, and there are other sun gods in different regions and at different times. The Egyptian civil calendar is divided into 12 months in a year, 30 days a month, 360 days a year, and then 5 days are added, with 365 days as a year. However, in reality, this calendar is not precise. Because an astronomical year is 365.25, the Egyptian civil calendar is one day behind the astronomical calendar every four years. In the ancient world, however, this was the best calendar. The Julian calendar in Rome was created by J. Caesar using the solar calendar of ancient Egypt plus the leap year. The medieval Roman pope Gregory reformed the Julian calendar and has become a universally recognized Gregorian calendar today. In this respect, the significant contributions of the ancient Egyptians can also be seen. ^[2]

Astronomy astrology

Astronomy should be separated from astrology. The latter is a pseudoscience that attempts to predict the fate of a person through the state of the celestial body. Although their origins are similar, they were often mixed in ancient times. However, contemporary astronomy is clearly different from astrology: modern astronomy is a discipline that uses scientific methods to study celestial bodies; while astrology corresponds to the positions of celestial bodies and personnel through methods such as comparison and association; in short, Astrology focuses on predicting the fate of people. ^[2]

Astronomy subject

The branches of astronomy can be divided into theoretical astronomy and observational astronomy. Astronomical observers observe the sky all year round, and after collating the information obtained, it is possible for theoretical astronomers to develop new theories to explain and predict natural phenomena.

Theoretical astronomy

Observation Astronomy

According to research methods, astronomy can be divided into:

Astrometry

Celestial mechanics

Astrophysics

Astronomical technology and methods

According to observation methods, astronomy can be divided into:

Optical astronomy

Radio astronomy

Infrared astronomy

Space astronomy

Other more subdivided disciplines:

History of Astronomy

Amateur astronomy

cosmology

Galaxy astronomy

Super Galaxy Astronomy

Far infrared astronomy

Gamma Ray Astronomy

High Energy Astronomy

Radio astronomy

Solar System Astronomy

Ultraviolet astronomy

X-ray astronomy

Astrogeology

Plasma astrophysics

Relativistic Astrophysics

Neutrino Astrophysics

Earth astronomy

Planetary physics

Cosmic magnetohydrodynamics

Cosmic chemistry

Cosmic gas dynamics

Lunar science

Kinematic cosmology

Photo astrometry

Neutrino Astronomy

Orientation Astronomy

Nautical astronomy

Aviation astronomy

Extragalactic astronomy

Stellar astronomy

Stellar physics

Post-Newtonian celestial mechanics

Basic astrometry

Archeology astronomy

Space astrometry

Almanac Astronomy

Spherical astronomy

Radio astronomy

Radio astrophysics

Measured Astrophysics

Practical astronomy

Solar physics

Solar system chemistry

Galaxy dynamics

Galaxy astronomy

Astrobiology

Astrochemistry

Astronomical geodynamics

Astronomical dynamics ^[2]

Detailed chronology of astronomy

Events in Astronomy

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Astronomy BC

In 3100 BC, Stonehenge built by British ancients can accurately understand the 12 positions of the sun and the moon, and observe and calculate the rise and fall of the sun, moon, and stars in different seasons. ^[3]

The ancient Egyptians built the pyramids 4700 years ago, partly to observe the sun and other celestial bodies.

In the fourteenth century B.C., the oracle inscriptions (unearthed from Anyang, Henan) in China's Yin Dynasty have conventional records of solar and lunar eclipses, as well as the world's oldest sundial notes.

In the twelfth century BC, the end of the Yin dynasty in China was divided into twenty-eight places.

In the eleventh century BC, it was said that an observatory was established in the Zhou Dynasty in China, and the earliest measurement of the angle of Huang Chi was made.

China's Book of Songs Xiaoya contains the earliest reliable eclipse notes in the world (776 BC).

Since 722 BC, until the end of the Qing Dynasty, the days of using dry branches in China have never stopped. This is the longest diary method in the world.

About 700 BC, Chinese comet observations have been recorded in oracle bone inscriptions (unearthed in Anyang, Henan).

In the seventh century BC, China used Tugui to measure the winter solstice and summer solstice, and divided the four seasons.

In 687 BC, China had the earliest record of the Lyra meteor cluster.

In 611 BC, China had the earliest record of comets.

In the seventh century B.C., the Babylonians discovered the Salo cycle of the eclipse cycle.

In the sixth century BC, China adopted the seventeen-month method to coordinate the lunar and solar calendars.

In 585 BC, the ancient Greek Thales performed the first predicted total solar eclipse.

In 440 BC, the ancient Greek calendar found that the phase of the moon repeatedly appeared on the same date in the Gregorian calendar in 19-year cycles.

In the fifth century BC, the ancient Greek Odox proposed the concentric movement of the sun, moon, and stars around the earth.

In the fifth century BC, Parmenides and Democritus of ancient Greece demonstrated that the earth was spherical, and believed that the morning star and the faint star were the same Venus. And proposed that the Milky Way is made up of many stars.

In the fifth century BC, the ancient Greek Anasakura proposed the cause of the lunar eclipse and believed that the moon was bright due to the reflection of sunlight.

Around 350 BC, during the Warring States Period, China's Gand and Shi Shen compiled the first star list, later called the "Ganshi star list".

Around 350 BC, during the Warring States Period, it was recognized that the eclipse is a phenomenon of mutual hiding between celestial bodies (Shishen, China).

In the fourth century BC, Aristotle, the ancient Greek, published a book entitled "On the Heaven," and put forward the earth-centered theory.

In the fourth century BC, Democritus of ancient Greece put forward the theory of atomic rotation of the universe, thinking that the universe is in an empty space, consisting of countless swirling, invisible, indivisible atoms.

In the third century BC, Eratosthenes of ancient Greece used astronomical observations to estimate the size of the earth for the first time.

In the third century BC, the ancient Greek Aristak calculated the ratio of the distance between the sun and the moon to the earth for the first time, and the ratio of the size of the sun, the moon, and the earth, and proposed that the sun is the center of the universe and the earth orbits the sun.

In the second century BC, Sima Qian and others completed a piece of "Tianguanshu" in the "Historical Records" of the Western Han Dynasty.

In the second century BC, Hipak of ancient Greece compiled the first table of the sun and the moon and the first table of stars in the West; the precession was found, and the brightness of the star was divided into six magnitudes.

In the second century BC, the Han Dynasty in China adopted twenty-four solar terms for farming.

In 134 BC, the Chinese Han Dynasty's "Hanshu · Astronomy" had the first detailed record of the new star.

In 104 BC, the Han dynasty fabricated the "Early Calendar", which contained the precise cycle of solar terms, new hopes, lunar eclipses, and five stars. This is the first major reform of the Chinese calendar, but its accuracy is poor (China has fallen behind, Deng Pingping, etc.).

In the first century BC, the Western Han Dynasty invented the Armillary Sphere to measure the equator coordinates of celestial bodies.

In 46 BC, the Julian calendar (old calendar) was issued in Rome.

According to the Han Book of Five Elements, in 28 BC, China had the earliest sunspot record in the world. ^[2]

Astronomy after AD

0 to 1499 AD

During the Eastern Han Dynasty in the first century, a zodiac bronze instrument was created and the speed of the moon was found to be slow. The near moon was measured (Jiayu, China).

In the Eastern Han Dynasty from the 1st to the 2nd century, a water transport armillary sphere (ie, an armillary sphere or a celestial sphere) was created, and the angular diameters of the sun and the moon were measured at half degrees, and the angle of yellow-red intersection was 24 degrees. Put forward the view that moonlight is reflected by sunlight. The "Hunting Sky Theory" (Zhang Heng, China) at that time was summarized in the "Huntianyi Atlas" and "Lingxian".

In the second century, the ancient Greek Ptolemy compiled a more complete star catalog at that time, and first discovered the phenomenon of atmospheric refraction of starlight.

In the second century, the ancient Greek Ptolemy's "The Great" used the complex system of this round and the equal round to elaborate the "Earth Center Theory".

Around 230 years ago, Wei Shi of the Three Kingdoms discovered the limit of eclipse and eclipse, and calculated the eclipse fraction and the azimuth of the initial loss (Yang Wei, China).

Around 330 years ago, the Jin dynasty discovered the precession, and the measurement of the winter solstice shifted west to once every fifty years, which is more accurate than that in the west. He also wrote "An Tianlun", which argues that the sky is immeasurable, but still has its limits, and the free movement of celestial bodies is below this limit (China Yu Xi).

In the fourth century, the phenomenon of refraction of starlight was discovered in the late Qin Dynasty and given a correct explanation (Jiang Jiang, China).

In the fifth century of the Southern Qi Dynasty, the "Daming Calendar" was compiled. For the first time, the precession was taken into account, and the time of the intersection month and Jupiter was measured exactly.

In the sixth century, Zhang Zixin of China discovered that the sun moved faster in winter and summer.

Chinese folk circulated the seven volumes of "Bu Tian Ge" written by Dan Yuanzi of the Sui Dynasty, which played a great role in popularizing astronomical knowledge at that time. In the seventh century, Wang Ximing compiled the Han and Jin dynasties in the early Tang Dynasty to explain it.

In 619, the Tang Dynasty fabricated the "Yinyin Calendar" and changed Pingshuo to Dingshuo, the third major reform of the Chinese calendar (Fu Renjun, China).

In 725, the length of the meridian was measured for the first time in the world (Nangong, China).

In the early 8th century of the Tang Dynasty, the position of the stars was measured with a brass armillary instrument made by Liang Lingjun, and the zodiac coordinates of the stars were different from those of ancient times (Chinese monk and his party).

In 814, the Arabs measured the length of the meridian in Mesopotamia under the organization of Khalifa Al Mamun in Baghdad.

In the tenth century, the yellow-red cross angle was accurately measured, the precession constant was improved, and a more accurate sun-month running table was prepared (Arbatani, Arab).

In the 10th century, the Hakkamet astronomical watch was compiled (Ibn Younis, Arabia).

In 1054, there was the first record of a supernova in China's "History of Song", and the remains of the supernova formed the Crab Nebula seen today.

According to Mengxi Bi Tan, from 1067 to 1077, Wei Pu and others in the Song Dynasty formulated a "Feng Yuan calendar" (Shen Kuo, China) based entirely on the 24 solar terms.

In 1088, the Song Dynasty manufactured the Xiangyun Observatory, a pioneer of modern timepieces (Su Song, China).

In 1092, Song Dynasty's Essentials of New Imagery was a monograph on manufacturing methods for astronomical instruments (Su Song, China).

In 1247, the Song Dynasty stone carved astronomical map (now still in Suzhou) is the oldest surviving star map in China (Huang Chang, China).

In the thirteenth century, Iran's Naxi Laetin Tutsi compiled the Ilhan star list.

In 1252, Alfonso X of Spain compiled the Alfonso Star Chart.

In 1276, the Yuan Dynasty produced thirteen astronomical instruments, such as Jianyi, and created the "Time Grant Calendar" based on actual measurements. The abolition of the ancient calendar was the fourth major reform of the Chinese calendar. The calendar is basically the same as the modern calendar. It was promulgated in 1281 and implemented for about 400 years (Guo Shoujing, Wang Yan, Xu Heng, etc.).

In 1276, the Yuan Dynasty produced nearly 20 astronomical instruments (Guo Shoujing, China).

In 1385, the Ming Dynasty in China established an observatory in Nanjing, the world's first well-equipped observatory.

In 1420, the stellar table and planetary movement table were compiled based on actual measurements (Mongolian Wulu Bo).

1500 to 1800

In 1542, Copernicus, Poland, proposed the Center for the Sun, stating that the stars do not move, and that the earth rotates around its axis once a day every day and as a planet orbits the sun once a year.

In 1543, Copernicus, Poland, published "The Astronomical Movement Theory", "Since then, natural science has begun to be liberated from theology."

In 1572, Tycho Brahe, Denmark discovered the Cassiopeia supernova, the second nova in the Milky Way.

In 1582, many countries in Western Europe introduced the Gregorian calendar, the predecessor of the current Gregorian calendar.

In 1584, Bruno, Italy, "On Infinity, the Universe and the World" was published, defending and developing Copernicus's theory of the sun center.

In 1596, the first variable star (increase by two) was discovered by Fabrisch, Germany, and its brightness changed periodically.

In 1600, Bruno opposed the geocentric theory and supported Copernicus's ground theory, thinking that the universe was infinite, so he was burned to death by the church in Rome.

In 1604, Kepler, Germany, discovered the supernova Ophiuchus, the third supernova in the Milky Way.

From 1609 to 1619, Kepler, Germany, discovered the three laws of planetary motion based on data from Tycho Brahe's observations of planetary positions.

From 1609 to 1610, Italian physicist Galileo made the first astronomical telescope and used it to observe celestial phenomena and discover the mountains and valleys on the moon: the four largest moons of Jupiter, the profit and loss of Venus, the sunspots and the sun rotation. Recognizing that the Milky Way is composed of countless stars, it provides a series of strong evidence for Copernicus's theory.

In 1627, Kepler, Germany compiled the Ludolf Star Chart.

In 1631, the transit of Mercury was first observed (Gasandy, France).

In 1632, Galileo published the Dialogue on the Two World Systems of Ptolemy and Copernicus, demonstrating that Copernicus' "sun center theory" is a new blow to theology and scholastic philosophy after Copernicus. Important works in the history of modern scientific thought.

In 1639, the horoscope phenomenon of Venus was first observed by Horox in the United Kingdom.

In the seventeenth century, China's Xu Guangqi Ming Dynasty published the "Chongzhen Calendar", where the star catalogue was a more complete star map of China at that time.

In the 17th century, China's Xu Guangqi first used telescopes to observe astronomical phenomena in the late Ming Dynasty.

In 1645, China adopted Western data to revise the "Contemporary Calendar", the summer calendar. This is the fifth reform of the Chinese calendar.

In 1647, German Hevich published the first detailed moon map and the monthly phase map of each day.

In 1655, Huygens, the Netherlands, discovered Saturn's largest moon, Titan, the second largest satellite known to the solar system to date.

In 1659, Huygens of the Netherlands discovered the aura of Saturn.

In 1666, Cassini, France discovered the rotations of Mars and Jupiter.

In 1667, the Paris Observatory was established in France.

In 1671, Cassini, France, discovered a satellite of Saturn, Titan.

In 1672, Cassini, France, discovered a satellite of Saturn, Titan, and for the first time measured the exact distance between the sun and the earth.

In 1675, Cassini, France discovered a circular slit in the ring of Saturn.

In 1675, Britain established the Greenwich Observatory.

In 1678, the first South Star table was compiled by Harley, England.

In 1684, Cassini, France, discovered two moons of Saturn-Enceladus and Enceladus.

In 1692, British Newton proposed the "Classic Cosmology" from the mechanical mechanics system.

In 1693, Harley, England, discovered a long-term acceleration of the moon's movement.

In 1705, the first periodic comet was discovered in Harley, England, and its period was predicted to be about seventy-six years, and it was confirmed.

In 1712, the British Fransted compiled a large star list.

In 1716, Harley, England proposed a method to observe the transit of Venus to determine the parallax (or distance) of the sun.

In 1718, Harley, England discovered the star's autonomy, proving that the star is not "constant".

In 1725, Bradley, England, found that the aberration of light was a testament to the revolution of the earth.

In 1729, Bougueux invented a photometer to compare the brightness of celestial bodies.

In 1745, the catastrophe theory of the solar system caused by the collision of comets was proposed (Fabfon).

In 1747, the nutation phenomenon of the earth axis was discovered (Bradley, UK).

In 1749, the mechanics theory of precession and nutation was established (Dalambert, France).

In 1750, it was first proposed that the Milky Way was a flat system composed of all stars in the sky, shaped like a wheel (British Rattle).

In 1752, for the first time, the distance between the moon and the earth was measured by a triangular method (La Cay, Lalande, France).

From 1753 to 1772, a detailed lunar movement table was compiled, and for the first time a precise theory of the moon's movement around the earth was created (Euler, Switzerland).

In 1754, the hypothesis that tidal friction slowed the earth's self-transition and the destruction of the solar system was proposed (Kant, Germany).

In 1755, the method of measuring the longitude at sea by observing the angular distance between the moon and the stars was invented (Joy Meyer, Germany).

In 1755, "Introduction to the History of the Development of the Universe" came out, and put forward the hypothesis that the nebula condenses to form the sun and the planet (Kant, Germany).

In 1760, the basic principles of photometry were proposed and the birth of "photometry" (Bouquet, France) began.

In 1761, an infinite-level universe structure was proposed to illustrate the infiniteness of the universe in space (Lambert, Germany).

In 1767, the Greenwich Observatory in the United Kingdom began publishing a nautical almanac.

In 1772, published the rule of the distance between planets (Pod, Germany).

In 1781, Uranus (Fer Herschel, England) was discovered.

In 1781, the first Nebula table was published (Messier, France).

In 1782, the first double star list (Fer Herschel, UK) was compiled.

In 1782, the light-changing period of the Daling Five-Variable Star was determined, and it was thought that the cause of the light-variation was caused by a dark companion star orbiting it periodically. Two new variable stars (Goodrich, UK) were also found.

In 1783, the movement of the entire solar system in space was discovered, and the direction and speed were determined for the first time, confirming that the sun also has its own movement (British Ver Herschel).

In 1785, the spatial distribution and motion of stars were studied by statistical methods, and the first graph of the structure of the galaxy was obtained, which produced stellar astronomy (Fr Herschel, UK).

In 1787, the theory of solar system stability was proposed from mechanical analysis (Lagrange, France).

In 1787, two satellites of Uranus were discovered-Uranus, Eisius, and the first planetary nebula (Fer Herschel, England).

In 1789, two moons of Saturn-Enceladus and Enceladus (Ever Herschel, England) were discovered.

In 1796, the book "Explanation of the Universe System" was published, which proposed the nebula hypothesis of the origin of the solar system based on mechanics and physics (Laplace, France).

In 1797, a new method for calculating the orbit of a comet was proposed (Orbs, Germany).

In 1799, the book "Astronomical Mechanics" was published, establishing the perturbation theory of planetary motion and the theory of the shape of planets (Laplace, France).

In 1800, infrared radiation that was not visible in the solar spectrum was first discovered (Fr Herschel, UK).

1801 to 1899

In 1801, the first asteroid, Ceres (Piazzi, Italy) was discovered.

In 1802, it was discovered that the double stars have periodic movements around each other (Fr Herschel, England).

In 1809, the book "The theory of celestial body motion according to conic curve" was published, and the calculation method of planetary orbit was proposed (Gauss, Germany).

In 1815, a spectroscope composed of a straight tube, a triangular prism, and a telescope was created. Since then, "astronomical spectroscopy" has been created, and the black absorption lines in the solar spectrum have been discovered (Frondhofer, Germany).

In 1823, the "photometric paradox" of classical cosmology was proposed (Albers, Germany).

From 1833 to 1847, 3347 pairs of stars and 825 nebulae were discovered (John Herschel, UK).

In 1837, the position of the double stars was precisely measured using a hairspring micrometer, and many new double stars were discovered (Russia Vastrovy).

In 1837, the radiant heat of the sun was measured for the first time (Puyère, France, José Herschel, UK).

From 1838 to 1839, the annual parallax of the star was first determined, providing strong evidence for the revolution of the earth (Bessel, Germany, Va Stroy, Russia, Henderson, UK).

In 1843, it was found that the number of sunspots changed with a period of about 11 years (Schwab, Germany).

In 1844, the brightness grading method for observing variable stars was discovered, which promoted the rapid development of variable star research (Agrandel, Germany).

In 1844, according to the irregular changes of Sirius and Nanhe three movements, it is foreseen that they all have dark companion stars (Bessel, Germany).

In 1845, for the first time, a photograph of the sun was studied for helioscopy (Focco, Fissau, France).

In 1845, based on the irregularities of Uranus' movement, a new planet was predicted to exist (John Adams, England, Le Verrier, France).

In 1846, Neptune was discovered based on predictions calculated by the planetary orbit perturbation theory, which verified the law of universal gravity and confirmed Copernicus's solar system theory (Galler, Germany).

In 1846, Neptune's first moon, Neptune (Raschel, UK), was discovered.

From 1847 to 1877, considering the mutual perturbation between the major planets, the reorganization of the planet's motion table, and found the out-of-tolerance phenomenon of Mercury's precession (Leville, France).

In 1848, a satellite of Saturn-Titan (Bond, USA) was discovered.

In 1849, the satellite stability theory was proposed, which proved that Saturn's aura is not a continuous solid, but consists of countless small particles (Roche, France).

In 1850, some nebulae were found to have a vortex structure (Wyth Ross, UK).

In 1851, two Uranus moons were discovered-Uranus I and Uranus (Lassere, UK).

In 1851, it was discovered that geomagnetism and magnetic storms also had 11-year periodic changes that corresponded to changes in the number of sunspots (Ramant, Germany, Sabion, UK).

In 1852, the Bonn star catalogue (Grandel, Germany) was compiled.

In 1854, the hypothesis of the gravitational contraction of solar energy was proposed, which believed that the sun gradually contracted due to its own gravitational effect, and the potential energy was converted into thermal energy, maintaining its outwardly radiated energy (Helmholtz, Russia).

In 1857, the first successful photo of the star was taken and star photography (Bond, USA) began.

From 1857 to 1859, the first detailed moon photo was taken (Delaru, UK).

Establish the basic relationship between the luminosity and magnitude of celestial bodies (Bagson, UK).

In 1858, from the rotation of sunspots on the sun, it was found that the sun was not a solid spin, but was doing a "bad spin" like a fluid (Carrington, England).

In 1858, in Carrollton, Germany, and Carrington, England, the periodic changes in the latitude distribution of sunspots on the sun were discovered.

In 1859, Carrington in the United Kingdom discovered solar flares, and geomagnetic disturbances, magnetic storms, and aurora occurred at the same time as the flares appeared.

In 1859, German Zellner invented the photometer, which has been improved and used to this day.

In 1861, the first luminous catalogue of 226 bright stars was published (Zellner, Germany).

In 1862, according to Bessel's prediction, Sirius' dark companion was discovered. Prove that the law of gravity is also applicable to the study of celestial bodies outside the solar system (A. Clark, USA).

From 1863 to 1864, the chemical composition of stars and nebulae was studied by spectral analysis to confirm the chemical identity of celestial bodies (Sage, Italy, Hudgens, UK).

In 1863, the first basic star list AGK was compiled (chaired by O'Weill, Germany, international cooperation).

In 1864, using a spectroscope to study nebulae, revealed their gas structure, and found two special green spectral lines emitted by planetary nebulae (Hagens, UK).

In 1865, by spectroscopic analysis, some bright stars were found to contain elements such as sodium, iron, calcium, magnesium, and bismuth (Hagens, UK).

From 1866 to 1881, the comet spectrum was found to contain hydrocarbons, and it was confirmed that the comet not only reflects sunlight, but also emits light itself. The gas spectrum of the meteor is similar to the comet, indicating that the two celestial bodies are related (Hagens, UK).

1868

Discover the middle atmosphere of the sun, the chromosphere, and discover the helium element on the sun. Later, helium will also be found on the earth (Lochill, UK).

Using a spectroscope, for the first time a sundial was observed when it was not a solar eclipse (Jensen, France).

The first visual spectrum classification method of star spectrum was proposed, and stars were classified into four categories: white stars, yellow stars, orange stars, and red and dark red stars (Sage, Italy).

First determination of star's apparent velocity (Huggins, UK).

In 1869, the wavelengths of one thousand spectral lines in the solar spectrum were published and expressed in the new unit Angstrom (Egerstrom, Sweden).

In 1870, the flash spectrum of the sun and a special green spectral line from the corona were discovered. It was thought to be a new element, and it was not until 1941 that it was proved to be a forbidden line of iron, nickel, and calcium. .

In 1871, the speed of the sun's rotation was determined from the displacement of the spectral lines on the east and west sides of the sun (Wogel, Germany).

In 1874, bright stars up to the fourth magnitude were found concentrated on the large garden at an angle of 17 degrees with the silver path (Gould, USA).

In 1876, a kinetic theory for the formation of asteroid zone voids and the formation of Saturn's halo slits (Cuckwood, USA) was proposed.

1877

Propose the view that there is an "artificial canal" on the surface of Mars (Schiparelli, Italy).

Discover two small moons on Mars-Phobos and Phobos (A. Hall, USA).

It was discovered that the (crystalline) selenium and metal contacts produce a photovoltaic effect of electromotive force under light irradiation. Later American Frieze used this to make photovoltaic cells in 1883 (Wo Adams, UK).

"The Theory of Sound" was published, basically completing the mathematical theory of sound (British Rayleigh).

In 1878, based on the repulsive effect of solar radiation, a comet shape theory was established, and the comet tails were divided into three (Brechki, Russia).

1879

Established the theory of tidal friction, and proposed the theory of the origin of the moon, which believed that the earth was formed by the tidal force of the sun and part of the material was pulled out to form the moon (Joe Darwin, UK).

Applying the empirical formula between the radiation and temperature of the black body, the surface temperature of the sun is 6,000 degrees Celsius (Stuart, Austria).

From 1879 to 1882, a polarimeter was used to compile a large luminosity list of 4260 stars (measured by Love Pickering, USA).

In 1880, the variable star classification was proposed (American Pickering).

In 1881, the application of a resistance calorimeter to accurately determine the solar constant value of thermal radiation at the surface began the study of solar radiation (Langley, USA).

In 1881, a photo of a comet was taken for the first time (Jensen, France, Drapal, USA).

In 1882, observations confirmed that the long-term precession of Mercury's perihelion was out of tolerance, and its data was accurately measured (Newcomb, USA).

From 1885 to 1886, the spectral classification of stars was established (American Pickering, Ann Morrie).

In 1887, began to compile photographic sky map star catalogue (responsible for the Henry brothers of the Paris Observatory, international collaboration).

In 1887, a theory of stellar evolution was proposed based on the different star spectra to explain that stars are variable (Lochill, UK).

1888

Published "New General Catalogue" (NGC) (Dreyer, UK).

It was found that the apparent velocity of the Daling Five Variable Star changed periodically, thus confirming that it was an eclipse variable star (Wogel, Germany).

The Andromeda Great Nebula vortex structure was discovered by photographic observations (Roberts, UK).

In 1889, the first spectroscopic binary star was discovered (American Pickering, Ann, Morrie).

In 1890, he researched the mutual perturbation between Saturn and Jupiter, and established the precise theory of the movement of the two planets, Jupiter and Earth (Joe Hale, USA).

In 1891, the solar spectrophotometer was invented, and the solar spectrum was obtained (Herr, USA; Drendal, France).

In 1892, Jupiter's fifth moon, Europa (Barnard, USA) was discovered.

In 1892, according to Bessel's prediction, Nanhe III's dark companion star (Sherber, USA) was discovered.

In 1894, the "gravitational paradox" of classical cosmology was proposed (Seligel, Germany).

In 1895, the meteor structure of Saturn's halo was confirmed by spectral analysis (Killer, USA).

In 1898, a satellite of Saturn-Titan (Vick Pickering, USA) was discovered.

In 1898, Eros was discovered. This asteroid was less than 24 million kilometers away from Earth at near low points, so it was used to determine solar parallax (Witt, Germany).

1900 to 1919

In 1900, the British scientist Jill and the Dutch scientist Captain published the first southern photographic star catalogue containing the 450,000 star orientations-the Cape of Good Hope star catalogue.

American scientists Chamberlain and Moreton proposed the star or MSI hypothesis about the origin of the solar system.

In 1904, Dutch scientist Captain discovered the law of star motion, and proposed the "two-star flow" theory, which denied the hypothesis that the star's original motion is irregular.

American scientist Berion discovered Jupiter's sixth moon, Europa.

German scientist Haltman discovered that calcium was found in the interstellar medium.

In 1905, American scientist Berien discovered Jupiter's seventh moon, Europa.

In 1905, Danish scientist Herzpenlund discovered that two types of stars, K and M, are classified as "giant stars" and "dwarf stars".

In 1909, a special perturbation method was proposed to calculate the orbits of comets and planets.

In 1910, German scientists Chanel and Wilson measured the temperature of a star for the first time.

The German scientist Ka Schwartzside founded the statistical mechanics of stars and proposed an ellipsoidal distribution law of the speed of stars.

American scientist Schlesinger has proposed the "column method" for astrophotography negatives.

In 1912, China started using the Gregorian calendar.

Discovering the period-photometric relationship of Cepheid variable stars provides an effective method for determining the distance of distant celestial bodies (Levitt, USA).

For the first time, the Doppler effect was used to measure the apparent velocity of the spiral nebula (Andromeda Nebula) (Srivel, USA).

In 1913, a "spectral-photometric map" of stars was established, and the theory of the evolution of stars from giants to dwarfs was proposed (Hen Russell, Herzpenlon, Denmark).

In 1914, the rotation of the Andromeda Nebula was discovered (American Bis).

Discovery of Jupiter's ninth moon, Io (Sec. Nicolson, USA).

Create a "spectrum-photogram" of a globular cluster (Shaple, USA).

In 1916, the spectroscopic parallax method for finding the distance between stars was invented (Hua Adams, USA; Colescht, Germany).

Establish the theory of stellar internal structure (Eddington, UK).

In 1917, the tidal hypothesis of the origin of the solar system was proposed (Kings, UK).

In 1918, studying the structure of the Milky Way based on the distribution of globular clusters, it was found that the sun was not located in the center of the Milky Way (Shaple, USA).

From 1918 to 1924, the publication of the Henry De Lapar Star Catalogue listed the spectral types of more than 225,000 stars (Ann Morrie, Canon).

In 1919, the total solar eclipse observation was used for the first time to verify the effect of the solar gravitational field to deflect the stars (Edington, UK led the total solar eclipse observation team).

The true cycle of discovering sunspots and other activities is 22 years (Her, Hua Adams, USA). ^[2]

1920 to 1929

1920 AD

Discover the asteroid Heydargo, orbiting Saturn, the farthest asteroid known today (Bad, German-American).

For the first time, the diameter of a star was directly measured with an interferometer (Mikeson, Biss, USA).

Put forward a new theory of lunar motion and compile an accurate lunar table (Earl Brown, UK).

There was a big debate between the Captan universe and the Shappler universe.

Establish the ionization theory of stellar atmosphere structure, and derive the relationship between the thermal ionization degree and temperature of gas under thermal equilibrium (Shaha, India).

1922 AD

Invented the thermocouple method to determine the temperature of the planet (Koblenz, USA).

The infinite-class universe model was specifically proposed, and the galaxy was considered as the first-level celestial system, and it was proved that this structure does not exist "luminous paradox" and "gravitational paradox" (Swedish card Charlie).

1923 AD

Compiled into a precise crescent moon watch, used in the astronomical calendar (England Brown, UK).

1924 AD

Discover the stellar mass-photometric relationship. It is believed that very large stars cannot exist because the radiation pressure exceeds gravitational contraction (Eddington, UK).

The edges of the Andromeda Nebula and several other spiral galaxies were distinguished as stars, revealing the nature of the extragalactic nebula, and found that there are Cepheid variable stars on the outer spiral arms of the Andromeda Nebula. Nebula distance (Hubble, USA).

Discover the asymmetry of stellar motion (Strongburg, USA).

1925 AD

A morphological classification of extragalactic galaxies was proposed (Hubble, USA).

The idea that the Milky Way was synthesized for many times was first proposed (Lindbraat, Sweden).

Establish a taxonomy of open clusters (Trumpler, Switzerland).

The gravitational redshift of the spectral line of Sirius' companion star was discovered, confirming the presence of high-density matter on the white dwarf (British Wah Adams).

It is determined that the special emission line in the planetary nebula spectrum is a forbidden line caused by two ionizations of oxygen in a very thin density state, thereby denying the speculation that a new element exists (Bowin, USA).

1926 AD

Propose the theory of pulsation of Cepheid variable star light (Eddington, UK).

The first international longitude survey.

1927 AD

A classification of globular clusters (Shaple, USA) is proposed.

Discover the Milky Way's rotation and calculate the speed of the Sun's rotation around the Milky Way and the total mass of the Milky Way (Lindbraat, Sweden, Olt, Netherlands).

For the first time, the rotation of a star has been discovered (O. Strouvi, USA, Schein, USSR).

The invention of the quartz clock, which was later used as the standard time, confirmed that the earth's rotation fluctuated (Maryson, USA).

The non-uniformity of Earth's rotation is explicitly proposed to explain some deviations of the moon's motion (Dechter, the Netherlands).

1929 AD

Propose the theory of gravitational instability of the origin of celestial bodies (Kings, UK).

The relationship between the luminosity of galaxies and the redshift of their spectral lines was found, indicating that the light from the nebula exhibits a redshift of the spectral lines, and its value is directly proportional to the nebula distance (Harbor, USA).

1930 to 1939

1930 AD

According to the perturbation theory calculations of planetary motion, the discovery of Pluto is yet another verification of gravitation (Tombo, USA).

The invention of the "coronagraph" solves the difficulty of observing the corona during a total solar eclipse (Lieu, France).

Invented the refracting telescope (German B. Schmidt).

Discover sub-giants and sub-dwarfs (Stromborg, Kuiper, USA).

Measure the radiation and temperature of the moon (Ai Petit, Sai Nicholson, USA).

The discovery of interstellar light absorption in the Milky Way revealed the existence of diffuse matter in the interstellar space (Trumpler, USA).

1931 AD

The main component of Venus's atmosphere identified by spectral analysis is carbon dioxide (Wah Adams, Duham, USA).

From 1931 to 1933, from the spectral photos of Jupiter, Saturn, and other planets, we realized that the atmosphere on these large planets was rich in ammonia, methane, and hydrogen. Therefore, it was speculated that when the earth was formed, the atmospheric components were water, ammonia, methane and hydrogen. River, German-American Wilder).

1932 AD

Stable and persistent noise from radio reception and the discovery of radio waves from the Milky Way outside the solar system began the study of radio astronomy (Yansky, USA).

Lemet, Belgium proposed a model of the "primitive atom" explosion and expansion.

Soviet Leandau used the Fermi gas model to infer the mass of the star collapse.

1933 AD

From 1933 to 1938, molecules containing cyanide and hydride were found in the interstellar medium (Belgium Schwans, Canadian German Hertzberger, American Adam Adams, etc.).

The second international longitude survey.

1934 AD

China established Nanjing Purple Mountain Observatory.

The theory predicts that when a star collapses to a nuclear density, it will form a "neutron star" (Zwicky, USA, German German Bard).

It is proposed that the cooling celestial body with a mass greater than 1.3 suns will inevitably collapse ("gravitational cone of the American Indian").

1935 AD

Publish a summary table of stellar parallax (Schlesinger, USA, etc.).

1936 AD

Take meteor photo observations to confirm that most of the meteors belong to the solar system, and use the meteor observations to determine the density of the Earth's upper atmosphere (Viber, USA).

Discover seasonal changes in Earth's rotation rate (Stoic, France).

1937 AD

The Heidelberg Astronomical Computing Institute of Germany has compiled a basic star list of FK8 including 1,535 stars.

1938 AD

It is proposed that hydrogen on the sun and stars is nuclear fuel, carbon is a catalyst, and helium is the main mechanism of thermonuclear reaction of ashes to clarify their energy sources (Betty, German, Kritzfield, USA, von Wetzsack, Germany) .

Discover two moons of Jupiter-Europa and Europa (Sec. Nicolson, USA).

Compiled into a total star list including 33,342 basic stars' positions and autonomy (Bose, USA).

1939 AD

Confirm the non-uniformity of the Earth's rotation (Spencer Jones, UK).

The first "flare star" was discovered, and its brightness changed in a short period of time (Fanmanen, the Netherlands).

From the study of the spin of the Andromeda Nebula, it is deduced that its total mass is equivalent to that of the Milky Way (Hobbacock, USA).

According to the general theory of relativity, it is expected that in the final stage of gravitational collapse, stars will form "black hole" super dense stars (Oppenheimer, Snyder, USA).

1940 to 1949

1940 AD

From 1937 to 1940, the first nine-meter-diameter parabolic antenna radio telescope was established to study the intensity distribution of the cosmic radio, and it was confirmed that the radio intensity from the center of the Milky Way was the largest (Reeb, USA).

Establishing the Zodiac Theory (Weber, Netherlands).

Proposed the sundial morphology classification (American Love Petty).

1941 AD

The hypothesis that stars are condensed by interstellar dust matter through radiation pressure (Spitz, USA).

Invented a telescope with a meniscus lens (Soviet Mark Sutov).

Discover the material exchange process of close-range binary stars (American Russian O. Strouvi).

A neutrino theory on stellar evolution is proposed, and it is believed that after the hydrogen in the star is depleted, the star will become hotter due to further thermonuclear reactions, so that it is believed that life on Earth died due to overheating (American Russian Gamow ).

It is proved that the special line in the corona spectrum is the forbidden line generated by iron, nickel, calcium and other atoms when they are highly ionized, which solves the so-called new element mystery (Edron, Sweden).

1942 AD

The British Army radar detection station found radio radiation from the sun.

Proposed the electromagnetic theory of the origin of the solar system (Sweden Alfen).

Observe the asteroid method to accurately determine the parallax value of the sun and find the exact distance between the sun and the earth (Spencer Jones, UK).

1943 AD

Successfully resolved the core part of the Andromeda Nebula and its two elliptical companion nebulae into stars, fully confirming that the extragalactic nebula is the same massive celestial system as the Milky Way, ending the debate over the nature of extragalactic nebulae (American German Bard).

Proposed the theory of fluid turbulence on the origin of the solar system (Weizak, Germany).

From 1943 to 1946, the classification of the various sub-lineages of the Milky Way (Soviet Kokhakin) was proposed.

1944 AD

This paper proposes the theory that the stars in the Milky Way are divided into "two-star family" (American German Bard).

Propose the meteorological hypothesis of the origin of the solar system (Soviet Austria Schmidt).

Saturn's largest moon (Titan) was found to have an atmosphere, and its main component was methane (American Dutch Kuiper).

Van Derhus in the Netherlands predicted the existence of radio waves of 21 cm wavelength emitted by interstellar neutral hydrogen based on the ultrafine structure of the hydrogen atom microwave.

1945 AD

Creation of Stellar's six-color metering system (Staplen, USA).

1946 AD

The first large-scale use of radar to study meteor showers (Lofoort, UK).

Spheroids were found, believed to be the embryos of stars (German-American Polk).

For the first time, the United States used radar to detect the moon.

The first "radio star" was discovered, and later referred to as "radio power source" (Heather, Parson, Jay Phillips, UK).

A new theory of stellar evolution was proposed based on the thermonuclear reaction theory (American German Schwartzside).

1947 AD

From 1947 to 1948, he took pictures of the Milky Way's core with infrared light and studied its structure (Staple, USA, Kalynik, Krasovsky, Nikonov).

Discover the young Star Group-Star Association (Soviet Amba Chumian).

Sikot-Alin meteorite landed in Soviet Siberia.

1948 AD

A satellite of Uranus, Uranus, was reversed from east to west (Dutch American Kuiper).

Invented the automatic guide device for telescope observation (Ho Babcock, USA).

Discover the magnetic field of the star (Babcock and Son, USA).

A homogeneous, isotropic, and steady state expanding universe model is proposed, so that matter and energy are continuously produced from nothingness, and the total entropy of the universe never increases (Bondi, Gold, Hoyle, UK).

1949 AD

Put forward the theory of stellar matter ejection (Soviet Fessenkov).

Proposed the protoplanet hypothesis of the origin of the solar system (Dutch American Kuiper).

Invented the radio frequency divider (Wild, MacLeeds, Australia).

A special asteroid Icarus was discovered with a perihelion distance of less than 0.2 astronomical units and could enter Mercury's orbit (American German Bard).

The Paloma Observatory in the United States installed a reflecting telescope with a diameter of five meters.

Discover Neptune's second moon, Neptune (Dutch-American Kuiper).

The star light polarization effect and the Faraday rotation effect of the radio wave band were discovered, which proves that the Milky Way has interstellar matter and a magnetic field (Hilltner, Joel Hall, USA).

Propose the original fireball theory of the origin of the universe (American Russian Gamow, etc.).

Made the first "atomic clock", now called "ammonia molecular clock" (absorptive type), which is of great value for establishing a reference for frequency and time and proofreading astronomy (Li Rong, USA).

1950 to 1960

1950 AD

Propose the theory that a comet was formed by the collapse of a large planet (Ourthe, the Netherlands).

Discover radio waves from extragalactic galaxies (British Brown, Hazard, Australia).

Use the computer to recalculate the movement table of the five planets from 1653 to 2060 (Clemens, De Brouville, Aike, USA).

The discovery of various forms of material bridges between galaxies confirms that the space between galaxies is not a vacuum, indicating that some galaxies are physically related (Zwicky, American Swiss).

Found false zodiac light (Soviet Fessenkov).

1951 AD

Put forward the turbulence hypothesis about the origin of celestial bodies (Weizak, Germany).

Discover the twelfth moon of Jupiter-Europa. It is a reversal from east to west (USA Nixon).

Invented the electronic telescope and photoelectric imaging technology (Laramand, France).

21 cm radio radiation of galactic neutral hydrogen was found (Eun, Purcell, USA).

It is proved that the Milky Way has a vortex structure (Wei Morgan, USA, etc.).

Invented a large field of view Schmidt telescope for observing meteors and later satellites (Baker, USA).

Invented radio interferometer (Wo Christianson, Australia).

1952 AD

Prove that the Milky Way is a spiral galaxy (Oort, Netherlands).

It was confirmed that the Star Association near Perseus was expanding (Belaau, Netherlands).

The zero point value of the Zhouguang relationship of Cepheid variable stars was corrected, so that the original extragalactic galaxy distances were approximately doubled accordingly (Bad, German, American).

A new hypothesis for the origin of the solar system was proposed from a chemical point of view (Yuri, USA).

Invented the lunar camera to accurately determine the position of the moon (Markowitz, USA).

1953 AD

Found this super galaxy, this is the huge galaxy cluster where the Milky Way is located (Vogule, France).

Put forward the hierarchical structure hypothesis about the origin of celestial bodies (Hoyle, UK).

Star chains found in a chain-like structure are called star chains, indicating that stars form in the fiber nebula (Soviet Fessenkov).

Put forward the gravity reunion hypothesis of the origin of celestial bodies (Rait, USA).

Compiled the "Star's Horizon Velocity General Table", which lists the data of the velocities of 15,106 stars (edited by American Lai Wilson).

1954 AD

A mechanism for the formation of stars by a mixture of interstellar gas and dust under the action of a shock wave (Oort, Netherlands) is proposed.

Invented the superhuman aberration prism contour height meter to improve the accuracy of time measurement (Tanjon, France).

It is found that there are basic differences between the Hero diagrams of the two main star families, indicating that stars belonging to different star families have different evolutionary paths (Shandage, USA).

1955 AD

First radio radiation received from the planet (Jupiter) (Burke, UK, Franklin).

Made the first cesium atomic clock with a stability of one ten billionth of a second as a time standard (Esson, UK).

1957 AD

Soviet Amba Chumian put forward the "ultra-dense state explosion" theory of the origin of celestial bodies.

Fowler of the United States proposed that supernova nuclear reactions can produce superheavy elements, and believed that the first type of supernova explosion system was caused by spontaneous fission of plutonium 254.

China establishes Beijing Observatory.

According to the results of polarized light measurement, Olt and Wallraf in the Netherlands concluded that the magnetic field in the Crab Nebula is in the filamentary structure of the nebula, and the energy of the accelerated particles is sufficient to make this nebula a strong source of cosmic rays.

1959 AD

For the first time, the United States has detected solar radiation.

The Soviet Union launched a cosmic rocket to hit the moon and found it to have no magnetic field or radiation band.

The Soviet Union launched a lunar probe, and for the first time took a picture of the back of the moon.

1960 AD

Lear, England, estimates that Ish invented the comprehensive aperture method for radio telescopes.

Introduction Vision According to the resolution of the Eighth International Astronomical Association in 1952, the almanac was adopted from 1960.

In the 1960s, achievements were known as the "four major discoveries in astronomy": microwave background radiation, pulsars, quasars, and interstellar organic molecules. At the same time, humans have broken through the constraints of the earth and can observe celestial bodies in the sky. In addition to visible light, the ultraviolet, infrared, radio waves, X-rays, and gamma rays of celestial bodies can be observed. These have made great progress in space astronomy, and have a great impact on the achievements of modern astronomy.

2015 AD

New Horizons takes the clearest picture yet of Pluto

21st century

Introducing Magnification Using many different types of telescopes to gather information about the universe, astronomy has entered a new phase. Most telescopes are placed on Earth, but some telescopes are placed in space and follow orbits, such as the Hubble Space Telescope. Astronomers are now able to learn certain space information through the launch of space probes.

Over the years, astronomical observation methods have expanded from traditional optical observations to all electromagnetic wave bands from radio, infrared, ultraviolet to X-rays and gamma rays. This has led to the discovery of a large number of new celestial bodies and astronomical objects: quasars, active galaxies, pulsars, microwave background radiation, interstellar molecules, X-ray binaries, gamma-ray sources, etc., making astronomical research unprecedentedly prosperous and active.

A space telescope with a caliber of 2 meters has entered orbit and has begun to work. A batch of 10-meter-class optical telescopes will be completed. Very long baseline interferometric arrays and very long baseline interferometers in radio, extra-space telescope facilities in infrared, and advanced X-ray astronomy facilities in X-ray will soon be available. The gamma-ray observatory is already in operation. The power of these instruments is enormous and far exceeds the existing astronomical equipment. It can be expected that the use of these astronomical instruments will inject new vitality into astronomy and raise people's understanding of the universe to a new level. Astronomy is on the eve of a great leap. ^[2]

Astronomy Summary

Astronomy is a natural science that studies the structure and development of celestial bodies and the universe. The content includes the structure, properties, and operating laws of celestial bodies.

Human beings were born between heaven and earth and have been exploring the mysteries of the universe since an early age. Astronomy is therefore one of the oldest sciences. It was closely related to human labor and survival from the beginning. It shares six basic disciplines with mathematics, physics, chemistry, biology, and geosciences.

The study of astronomy is of great practical significance to our lives, such as giving time, compiling calendars, determining positions, etc. The development of astronomy has had a great impact on human nature.

A major subject of astronomy is the origin and evolution of various celestial bodies. The main research method of astronomy is observation, and the continuous creation and improvement of observation methods has become a subject of unremitting efforts of astronomers.

Unresolved problems in astronomy

Astronomy has made great progress in understanding the universe and its related characteristics. But there are still some astronomical questions that cannot be answered. To answer these questions, new astronomical instruments on the ground or in space may be needed, and new advances in theoretical or observational astronomy may be needed.

What is the source of the stellar mass spectrum? Why do astronomers observe the same stellar mass distribution (initial mass function) regardless of the initial conditions? A deeper understanding of the formation of stars and planets may be required.

Is there alien life? If there is alien life, is it intelligent? How to explain Fermi's paradox if there is intelligent alien life. Does the existence of extraterrestrial life have important scientific and philosophical implications-is the solar system unique?

What caused the universe to form? Is fine-tuning the universe hypothesis correct? Is it correct, is this the result of natural selection by the universe? What causes the universe to inflate, leading to a uniform universe? Why is there a baryon asymmetry?

What is the nature of dark matter and dark energy? Dark matter and dark energy determine the evolution of the universe and its destiny, but humans are still unclear about its essence. What will happen to the ultimate destiny of the universe?

How was the first galaxy formed? How are supermassive black holes formed?

What causes ultra-high-energy cosmic rays?

School of Astronomy

Among the first-level disciplines, there are 3 universities with Ph.D.1 authorization in the country. In 2012, there were 3 participants in the subject evaluation of the Ministry of Education; A total of 5 participating universities. Note: The following colleges with the same score are listed in order of school codes. ^[2]

Astronomy development prospects

It is understood that there are not many universities in China that offer astronomy majors at the undergraduate level. There are only a few universities such as Nanjing University, Peking University, University of Science and Technology of China, Beijing Normal University and Guangzhou University. From a master's degree, it can be said that astronomy is a discipline that requires long-term research and a solid foundation in science. Astronomy is a discipline that intersects with applied disciplines such as aerospace, geodesy, and national defense. After graduation, students can develop their talents in these fields. According to the statistics of related positions in astronomy major, the area with the best employment prospects for astronomy major is Wuhan. Ranked 1st in "Astronomy".