What's the use of astronomy in our life?

Astronomy is the discipline of observing and studying celestial bodies in the universe. It studies the distribution, movement, position, state, structure, composition, nature, origin and evolution of celestial bodies, and is a basic subject in natural science. A remarkable difference between astronomy and other natural sciences is that the experimental method of astronomy is observation, through which all kinds of information of celestial bodies are collected. Therefore, the study of observation methods and means is a direction that astronomers strive to study. In ancient times, astronomy was also closely related to the formulation of calendars. Modern astronomy has developed into the science of observing all electromagnetic waves.

Astronomy is an ancient discipline with a history of at least several thousand years. Astronomy occupies a very important position in early human civilization. In ancient times, people determined the time and direction by observing the sun, moon and stars with naked eyes, made calendars and guided agricultural production, which was the earliest beginning of astrometry. On this basis, astrology was born, that is, predicting bad luck, natural disasters, winning or losing wars and personal destiny through the operation of celestial bodies.

In the 2nd century A.D., Ptolemy, an ancient Greek astronomer, put forward the geocentric theory that cosmic objects, including the sun, revolve around the earth. This theory was welcomed by the church and dominated the western society's understanding of the universe for more than 1000 years. /kloc-in the 6th century, Copernicus, a Polish astronomer, put forward a new theory of cosmic system-Heliocentrism. 16 10, Italian astronomer Galileo made astronomical observations with a telescope for the first time, observing sunspots, the surface of the moon, the planets' losses and the four moons of Jupiter. Newton, a famous British physicist, put forward the law of universal gravitation and founded classical mechanics, which promoted the birth of a new branch of astronomy, celestial mechanics, and made astronomy enter a new stage of studying the interaction and motion reasons between celestial bodies from simply describing the geometric relationship and motion of celestial bodies, which was a huge leap in the history of astronomy.

/kloc-The invention of astrophotography and spectroscopy in the mid-9th century enabled astronomers to further study the physical properties, chemical composition, motion state and evolution law of celestial bodies, thus further studying the nature of problems, thus resulting in a new branch of astrophysics. This is another leap in astronomy.

After the end of the Second World War in the 20th century, radio telescopes began to be widely used in astronomical observation, opening a new window of electromagnetic spectrum except visible light, and made new achievements called "Four Great Discoveries in Astronomy" (microwave background radiation, pulsars, quasars and interstellar organic molecules) in the 1960s. With the continuous improvement of human technology, space astronomy has developed rapidly. Humans can break through the barrier of the earth's atmosphere and observe celestial radiation in ultraviolet, infrared, X-ray, γ-ray and other bands outside the earth, and astronomy has entered a new era of full-band development. At the same time, the aperture and resolution of ground-based telescopes are constantly improved by new technology, from 4-meter, 5-meter and 6-meter telescopes to some 8-65 and 438+00-meter telescopes in the 1990s. Together with space astronomical satellites, these telescopes have accumulated a large amount of observation data and found active galactic nuclei, gamma-ray bursts, X-ray binaries, gravitational lenses, dark matter and dark energy.

Research objects and fields of astronomy

Astronomy studies various celestial bodies in the universe. With the development of astronomy, the scope of the universe observed by human beings is constantly expanding. According to the size of celestial bodies, the research objects of astronomy can be divided into:

Planetary scale: including planets in planetary system, satellites orbiting planets and a large number of small celestial bodies, such as asteroids, comets, meteoroids and interplanetary matter. The solar system is the only planetary system that can be directly observed at present. But there are countless planetary systems like the solar system in the universe.

Star scale: Now people have observed hundreds of millions of stars, and the sun is just a very common one among countless stars.

Galaxy scale: The solar system is in the Milky Way and consists of tens of billions of stars. The Milky Way is an ordinary spiral galaxy, and there are many extragalactic galaxies outside the Milky Way. Galaxies have further formed galaxy clusters, galaxy clusters, supercluster and other larger celestial systems.

Cosmic scale: Some astronomers have proposed that the total galaxy is one level higher than the supercluster, which is the cosmic range that can be observed by human beings at present, with a radius of more than 65.438+000 billion light years.

For distant celestial bodies, it takes a long time for their light to be received by people. For example, for a celestial body 1 100 million light years away, what people actually observe is the image of it 1 100 million years ago. This shows that the physical properties of celestial bodies not only reflect their own forms, but also reflect their evolution stages. Many celestial bodies observed by people are actually samples on a large time scale, which can provide clues for their evolution over hundreds of millions of years. Therefore, according to statistical classification and theoretical research, astronomers can establish a complete celestial evolution model.

One of the hottest and most unconvincing topics in astronomical research is the study of the origin and future of the universe. There are endless theories about the origin of the universe, among which the most representative, influential and supportive one is the Big Bang theory put forward by American scientist Gamov and others in 1948. According to this theory, the universe was born in a violent explosion about 654.38+03.7 billion years ago. Then the universe expands, the temperature drops, and all kinds of elementary particles are produced. With the further decline of temperature of the universe, matter began to collapse due to gravity, and gradually condensed. When the age of the universe was about 1 100 million years, galaxies began to form and gradually evolved into what they are today.

Astronomy and astrology

Astronomy should be separated from astrology. The latter is a pseudoscience that tries to predict a person's fate through the running state of celestial bodies. Although their origins are similar, they often mixed together in ancient times. However, there are obvious differences between contemporary astronomy and astrology: modern astronomy is a subject that uses scientific methods to study celestial bodies; Astrology corresponds the position of celestial bodies to people through comparison and association. Simply put, astrology focuses on predicting people's fate.