What does the sun mean? What does solar time mean

The Sun is the central body of the solar system and occupies the overall mass of the solar system. The eight planets in the solar system, asteroids, meteors, comets, outer Neptune objects, and interstellar dust all revolve around the Sun, which revolves around the center of the Milky Way.

The Sun is a star located at the center of the solar system, and it is almost an ideal sphere intertwined with hot plasma and magnetic fields. The diameter of the Sun is about 1,392,000 (kilometers, equivalent to 109 times the diameter of the Earth; It is about 1.3 million times the size of the Earth; Its mass is about 2 10 kilograms (330,000 times that of the Earth). In terms of chemical composition, about three-quarters of the mass of the Sun is now hydrogen, and almost all of the rest is helium, including oxygen, carbon, neon, iron, and other heavy elements with less than 2% of the mass, which uses nuclear fusion to release light and heat into space.

The Sun is currently passing through the local interstellar cloud in the local bubble of the Orion Arm at the inner edge of the Milky Way. At a distance of 17 light-years from Earth, there are 50 of the closest star systems (the closest star to the Sun is a red dwarf called Proxima Centauri, about light-years).

The Sun is a yellow dwarf (spectrum G2V), the lifespan of a yellow dwarf is roughly 10 billion years, and the Sun is currently about 100 million years old. In about 50 to 6 billion years, the Sun's interior will be almost completely depleted of hydrogen and the Sun's core will collapse, causing the temperature to rise, a process that will continue until the Sun begins to fuse helium into carbon. Although helium fusion produces less energy than hydrogen fusion, it is also hotter, so the outer layers of the sun will expand and release a portion of the outer atmosphere into space.

At the end of the process of turning to new elements, the mass of the Sun will decrease slightly, and the outer layers will extend to the current orbit of the Earth or Mars (at which point the two planets will be farther away from the Sun due to the decrease in the mass of the Sun).

The sun"It's a star"The sun"It represents --- brightness.

The sun has at least two meanings.

One, it is the sun in the astronomical sense.

Second, it is the sun in the theory of traditional Chinese medicine. In fact, the theory of Chinese medicine also comes from the theory of the I Ching.

The sun illuminates all things in the world. There is no sun. There was nothing left.

The sun is the name of a planet.

Solar time refers to a method of measuring time based on the position of the sun in the sky. Specifically, when the sun crosses a particular meridian, it is called the noon hour of that place. When the sun passes one degree in the sky, four minutes have passed.

Therefore, the length of the solar time is uneven because the speed and orbit of the sun are uneven. The calculation of solar time is mainly used in astronomy, navigation, and other fields, while the calculation of modern time is mainly based on international atomic time.

A time measurement method that uses the solar mid-celestial time at a certain place on the earth as the reference time. Specifically, the local solar mid-heaven moment in Zhishu refers to the moment when the sun is at its highest point on the local meridian. This method of time measurement is one of the earliest time measurement methods adopted by ancient humans.

The solar time varies from location to location because the Earth is not a perfect sphere, but takes on a complex shape, and the Earth's rotation is not uniform. As a result, solar time varies across the globe. In order to harmonize the measurement of time, global standard time such as standard time and coordinated universal time were used instead of solar time.

The Sun is the closest star to Earth and is the central body of the solar system.

The Sun, which accounts for about three-quarters of the total mass of the solar system, is hydrogen, which releases light and heat into space by means of nuclear fusion, orbiting around the center of the Milky Way for a period of about one year, and also rotating from west to east around its axis. The Sun is a yellow dwarf, about 100 million years old.

Most of the materials that make up the sun are ordinary gases, of which hydrogen accounts for about 27% of helium and 2% of other elements. The sun can be divided into nuclear reaction zone, radiation zone and convection zone, and solar atmosphere from the center outward. The atmosphere of the sun, like the atmosphere of the earth, can be divided into various layers according to different heights and different properties, that is, from the inside to the outside, it is divided into three layers: the photosphere, the chromosphere and the corona.

The surface of the sun, which we usually see, is the lowest layer of the solar atmosphere, and the temperature is about 6,000 kilo. It is opaque, so we can't see directly the inner structure of the sun. However, astronomers have established models of the Sun's internal structure and physical state based on physical theories and the study of various phenomena on the surface of the Sun.

There are two concepts of solar day, one of which is the concept of folklore, which speaks of the birthday of the sun. It is the 19th day of the sixth month of the lunar calendar, and it is recorded on the yellow calendar. The second refers to the "Riyao Ri" in the ancient Chinese "Seven Yao", which is secretly coinciding with the Western Sunday.

The Sun Day, the predecessor of Sunday, has been a day of rest since ancient Rome, and people have been engaged in worship without having to work. Latin, dies solisSunday refers to the day after Saturday and before the following Monday.

The Latin name for Sunday is dies solis, which means the day of the sun; The French word is dimanche, a Latin word meaning "day of the Lord"; English is sunday, ** on the day of the sun; The Russian word is meaning "Sunday".

How the solar day is calculated

A solar day is equivalent to a day and night on Earth, which is the time of a day and a night. Of course, the solar day mentioned here does not mean that the earth really rotates for one week, but the time interval when the sun passes through the same place, like the meridian plane of the earth, and the earth is also making a revolution when it rotates.

The time for the earth to rotate around is about 23 hours, 56 minutes and 4 seconds, and there is also an revolution, which takes 3 minutes and 56 seconds to revolution, so that the total time of rotation and revolution is exactly 24 hours. The time for the earth to rotate around is called a sidereal day, and there is a difference between the sidereal day and the solar day, in simple terms, the difference between the two is about 4 minutes, and the solar day is a little longer than the sidereal day.