In what year of the 20th century was the Milky Way rotation discovered

The first to study the rotation of the Milky Way was. Struvey. In 1887, he used his own data to study the rotation of the Milky Way.

At that time, due to the lack of data and low accuracy, it was not possible to obtain a positive view of the rotation of the Milky Way. In 1924, Stromberg proposed the hypothesis of the rotation of the Milky Way based on the asymmetry of the stellar motion. In 1927, Aort theoretically introduced a formula for the influence of the Milky Way's poor rotation on the radial velocity of stars and the self-rotation of the silver meridian (i.e., Oort's formula), and confirmed the rotation of the Milky Way through the analysis of the radial velocity of the star.

Before the 40s, the study of the rotation of the Milky Way mainly used optical observations, such as radial velocity, self-determination, etc. However, this method has significant limitations and can only provide information within 3 4 thousand parsecs from the Sun; At greater distances from the sun, the information provided is unreliable. Immediately after the advent of radio astronomy, a 21-centimeter spectral line emitted by neutral hydrogen was observed in the Milky Way.

Based on the displacement of the 21 cm spectral line of neutral hydrogen, the radial velocity of the neutral hydrogen cloud can be obtained, and thus the rotation velocity of the Milky Way can be deduced. At present, radio observation of neutral hydrogen 21 cm spectral line has become the most important method to study the rotation of the Milky Way.

In 1887, the scientist Struve used his observations to study the rotation of the Milky Way for the first time.

In 1927, the Dutch astronomer Oort gave evidence of the Milky Way's rotation by conducting a detailed analysis of the radial velocity of stars.

But the rotation of the Milky Way galaxy is different from that of solids, and the speed of rotation varies from the center to the edge of the silver disk.

Oort formula.

Ault deduced the formula for calculating the rotation of the Milky Way from the apparent velocity of the star and its own as:

where δv is the effect of the Milky Way's rotation on radial velocity; l-l is the silver meridian difference between the star and the galactic heart; b is the sidereal galactic latitude (see celestial coordinate system); v

is the radial velocity; μ

for the silver by itself; r

is the distance from the star to the sun; a

and b are the Oort constants, and their expressions are:

where r is the distance from the sun to the center of the galaxy; ω

is the angular velocity of rotation of the Milky Way; =d/dr

The Oort formula only applies to the range of 1 2 thousand parsecs near the Sun, and further afield, these two formulas are not accurate enough.

Oort constant.

For decades, many astronomers have determined the rotation of the Milky Way through the analysis of the radial velocity and self-data of O-B stars, Cepheid variables, supergiants, galactic clusters and other celestial objects

b-value. The current common values are:

a = +15 km (seconds, thousands), b = -10 kilometers (seconds, thousands), r = 10 thousands. From this, it can be calculated that at the Sun, the Milky Way has an angular velocity of rotation of 00053 per year, a linear speed of rotation of 250 kilometers per second, and a rotation period of years.

N "celestial bodies" in the universe form a "system".

"How does the department revolve around the celestial bodies?"

Whether the "Milky Way" is hidden in a larger "system" has not been confirmed.

At the center of the Milky Way is a dense zone of stars, where the density of nebulae is high, which affects visible wave observations, and it is generally believed that there is a super black hole inside. The Milky Way will be autobiographical, most of the stars revolve around the core of the Milky Way and form a cantilever result, and our solar system is also in one of the cantilever structures, and it will also turn around.

Several relatively close galaxies form a galaxy group, generally the galaxy group composed of the Milky Way and several nearby galaxies is called the local galaxy group, and each member of the galaxy group will also circle each other, just like a multi-star system, but the speed is very slow on the cosmic scale, and it generally takes millions of years to change significantly, for example, our galaxy and the Andromeda galaxy collide in billions of years.

At the center of the Milky Way is a massive black hole, or a group of black holes orbiting each other. As for whether the Milky Way will rotate. To be honest, it's not clear.

Because galaxies are so big. If the Milky Way has an revolution. One thing is for sure, the definite period is on the order of a billion years.

For a movement in such a huge range. Not to mention the hundreds of years after the invention of the telescope, even the entire history of mankind is not enough to observe its relative displacement. So at the moment all the people who say that there is a revolution or there is no revolution are speculation.

And it's all speculation with no credible basis.

At the center of the banking system is a high-density and high-temperature material, and at high speed of rotation, a large amount of matter is thrown into the universe, and our solar system is thrown out. The center of the Milky Way is not a black hole, and the density of its center is gradually decreasing due to the large amount of burning waste thrown out.

The Milky Way does not orbit, it just floats in the universe, and like other galaxies, the total galaxy does not really exist.

The Milky Way does not revolve around a galaxy (not currently discovered), and the Milky Way and other extragalactic galaxies are moving away from each other (the principle is unknown).The expansion of the universe refers to the fact that the distances between galaxies are increasing.

In the middle of the Milky Way is a black hole, and I think the Milky Way will revolve around a galaxy that is bigger than the Milky Way.

No, there must be some kind of connection between the two, it's just that it hasn't been discovered yet, but it's certainly not a coincidence.

I don't think it's a coincidence, it may be a manifestation of parallel universes, after a long discussion among scientists, all scientists think that this can be a coincidence, but when this phenomenon has not been resolved, there is a third identical information, so this is the chain to make it clear that it is not a twin event of the universe, but three galaxies.

I don't think it's a coincidence, the Milky Way is the same as the solar system, they are all independent mechanisms and simple systems, their operating laws and operating mechanisms are relatively unified, and they have their own operating characteristics.

The principle of the formation of the silver ring:

Billions of years ago, galaxies were chaotic and chaotic, but over time, they gradually rotated to form disk-like systems. The larger the galaxy, the more stable their weight will be, and the less they will merge with other celestial bodies over time. The redshift survey, called Deep2, surveys galaxies between 2 billion and 8 billion light-years from Earth.

The larger the system of galaxies, the more stable they seem to be. Susan Cassin, an astronomer at the Greenbelt Goddard Space Flight Center in Maryland, USA

"Astronomers believe that the disk-shaped galaxies in the nearby universe were what they are today as early as 8 billion years ago, and that there has been little change since then. However, our observations show that these galaxies are steadily changing over time.

The milky way is a barred spiral galaxy where the solar system is located, including 1000 400 billion stars and a large number of star clusters, nebulae, and various types of interstellar gas and interstellar dust. The Milky Way, with a total mass of about a trillion times that of the Sun, belongs to the local group of galaxies, and the nearest extragalactic galaxy is the Dwarf Canis Major galaxy 10,000 light-years away.

The Milky Way is the star system in which the solar system is located, including 1500 400 billion stars and a large number of star clusters, nebulae, as well as various types of interstellar gas and interstellar dust, black holes, and its total visible mass is 1 5 trillion times the mass of the Sun.

The projection of the Milky Way in the sky is like a glittering river flowing in the sky, so it was called the Milky Way or Tianhe in ancient times, and the Milky Way can be seen all year round, but the brightest and most spectacular part of the Milky Way is seen at the turn of summer and autumn.

The Milky Way and the Milky Way.

All the stars we see with the naked eye, as well as many stars that are too faint to be seen with the naked eye, including our Sun and our solar system, belong to a huge star system, the Milky Way. The Milky Way also includes many star clusters, interstellar media, and nebulae.

I don't know the true face of Lushan, only because I am in this mountain. "We are in the middle of the Milky Way, and what we can see is a Milky Way across the night sky. It was a hazy band of light that stretched across the sky for a full week.

The average width is about 20 degrees. The Milky Way is made up of many distant stars, indicating that the Milky Way is very dense in this area. Many dark bands can also be observed in the Milky Way, indicating that there is a large number of interstellar media and dark nebulae in the direction of the Milky Way.

The structure, size, and movement of the Milky Way.

The discovery of extragalactic galaxies has allowed us to learn about our Milky Way through them.

It is now known that at the center of the Milky Way is a protruding nuclear sphere with a radius of more than 10,000 light-years, which is very dense and filled with thick interstellar media and nebulae. The Milky Way also has a flat disk called a silver disk. The hard disk is densely populated with stars, as well as various interstellar media and nebulae and star clusters.

The silver disc is more than 100,000 light-years in diameter and only a few thousand light-years thick. The Milky Way we see is formed by the clustering of distant stars in the silver disk. A very striking structure of the silver disk is the spiral arms that have spiral arms, so the Milky Way belongs to the spiral galaxy.

In addition to the nuclear sphere and the silver disk, the Milky Way also has a large halo called the silver halo. There are very few stars in the galactic halo, and there are a few globular clusters. The radius of the galactic halo may stretch as far as 300,000 light-years.

The Milky Way has a rotational motion, but it does not rotate as a whole like our Earth. The speed of the Milky Way's rotation initially increases with the distance from the center of the Milky Way, but stops increasing after hundreds of thousands of light-years until it remains roughly the same far into the galactic halo.

The Sun is located in the Milky Way in the Milky Way, about 10,000 light-years from the center of the Milky Way. The speed at which the Sun participates in the rotation of the Milky Way is more than 200 kilometers per second. Assuming that all stars in the Milky Way have the same mass as the Sun (which is not true), then it can be deduced that there are about 100 billion stars in the Milky Way.