How many stars are there in the solar system and how many stars are there in a galaxy?

Except for the sun, all planets in the solar system do not revolve around the sun. It turned out to be nine planets, and now Pluto has been "expelled" because it is too small to form the scale of a "star". It is currently known as the Eight Planets.

A solar day is 24 hours, based on the position of the Sun as a reference, and a sidereal day is 23 hours, 56 minutes and 4 seconds, with a distant background star as a reference, because the star is so far away, it can be seen as fixed. The reason why it is about four minutes, because the earth revolves around the sun at the same time, the revolution is different, because they will be in the direction from west to east, so in the background of the earth the star rotates 1 week 23:56:04 seconds, because during this period, the earth revolves around the sun about the same time, so that the earth puts this again, in order to make the sun in the same position in the sky, i.e. relative to the sun of a week, this time is 3 minutes and 56 seconds, so one solar day is long.

This may be more abstract, and the owner can draw to show intent to help with understanding.

One star, 2 stars you don't want to live anymore??? The heat is killing you ...

There is only one star in the solar system, the Sun.

One, that is, the Sun, it is an ordinary star with a surface temperature of 5500

Not necessarily. There are large and small galaxies, and the number of stars in a galaxy can be as small as possible.

Our own galaxy.

It is a barred spiral galaxy with a huge disk of galaxies, about 30,000 parsecs in diameter.

or 100,000 light-years, or about 3,000 light-years thick; It has about 300 billion stars.

The Great Galaxy of Andromeda.

It is larger than the Milky Way and is the largest galaxy in the group. It has twice the mass of the Milky Way, is at least twice as large as the Milky Way, and contains twice as many stars as the Milky Way.

Most galaxies in the universe are dwarf galaxies, tiny galaxies that are less than one percent the size of the Milky Way and contain only billions of stars.

The Sun is a star. The closest star to Earth is the Sun. Older stars like the Sun rotate at a lower rate and have milder surface activity.

The Sun is the most typical star of the Milky Way, about 25,000 to 28,000 light-years from the center of the galaxy. The solar system moves at a speed of about 220 kilometers per second and makes one revolution in the galaxy for 22,600 years. The nine planets in the solar system all orbit in a near-circular orbit in about the same plane, orbiting the Sun in the same direction.

With the exception of Venus, the other planets have the same direction of rotation and revolution.

The Sun is the largest object in the solar system. It has the mass of the entire solar system. The sun is personified in many myths: the ancient Greeks called it helios, while the ancient Romans called it sol.

The Sun Sol is a G-type main-sequence star about 100 million kilometers away from us, which belongs to the star and is also a proper noun. It has a diameter of about 1.39 million kilometers and a power of watts, and the energy of one second is enough for one person and one heavy truck (more than 14 tons) in the world to circle the equator about 100,000 times, or hundreds of thousands of years in the world.

Stars are a universal concept that includes the Sun and at least a few trillion other stars in the observable universe, as well as historical and future stars, that emit light by their own nuclear reactions (black dwarfs and black holes, etc.). The above is not a definition). In contrast to planets, ancient people lived on the surface of the earth, did not have telescopes, and observed that most of the stars that were basically immobile during a person's life were stars, and it was the planets that were obviously moving.

Now we know that the position of stars in the sky is not fixed either.

The Sun is a true subset of stars, the closest star to us, and at the same time occupies the mass of the solar system, and the mechanism of its fusion reaction is not fully understood by humans, which is also one of the biggest mysteries of the solar system.

One, the sun.

The Milky Way is a barred spiral galaxy about 100,000 light-years in diameter and includes between 100 billion and 400 billion stars. The Sun is a typical star of the Milky Way, located on the branch cantilever Orion Arm, 10,000 light-years away from the center of the Milky Way, and the solar system rotates around the center of the Milky Way at a speed of about 240 s, one revolution in 100 million years.

The eight planets in the solar system all orbit in a near-circular orbit in about the same plane, orbiting the Sun in the same direction. With the exception of Venus, the other planets have the same direction of rotation and revolution. Most comets orbit in the same direction around the Sun, most of them have elliptical orbits, and generally have a long orbital period.