The distance between the sun and the earth

The distance between the sun and the earth

It's very difficult to find out how far the sun is from the earth. I read a Book: it says that it takes 8 minutes and 20 seconds for the sun to shine on the earth, and the speed of light reaches 300000 kilometers per second. To calculate the distance between the sun and the earth, we need to first change 8 minutes and 20 seconds into seconds. One minute is 60 seconds, a total of 8 minutes, and then remove 0 of 60

How do people calculate the distance between the earth and the sun?

The distance between the sun and the earth is called "astronomical unit" in astronomy. It is a very important number, and many astronomical figures are based on it, One is to use the transit of Venus (that is, the sun, Venus and the earth are just in a straight line); the other is to use asteroids to measure the distance between the sun and the earth. In history, the former method was used to measure the distance between the earth and the sun, and the average distance between the sun and the earth was also calculated in this way, that is, a beam of radar wave was sent from the earth to hit Venus, The average distance between the sun and the earth measured by this method is 149597870 km, about 150 million km

The distance between Neptune and the sun is 30 times that between the earth and the sun. It takes one year for the earth to circle the sun. How many years does it take for Neptune to circle the sun?

About 164.8 years

It seems that it can reach the speed of light
Suppose: we expand the radius of a turntable in the universe. When it reaches a certain degree, we only need to give a small angular velocity to the part close to the center, and then the outer linear velocity can reach the speed of light. Then, as long as we are on the edge of the turntable, we will be stepping on the time machine. Although the turntable will be large, it may take a lot of energy, But is this hypothesis true? Is it true that no object in the universe can exceed the speed of light?

Not to mention your hypothesis, first of all, the speed of light can not be surpassed is based on the actual theory, just like the second type of perpetual motion machine can not be realized (theoretically feasible, but in practice there can not be 100% efficient energy converter)

How to reach the speed of light

You can't reach the speed of light with a propeller!
Now the research is how to find the "space-time crack". If there is a space-time crack, there is no limit to the distance. If you want to go anywhere in the universe, "step one step" will be there!

How does light reach the speed of light?

Light is a kind of particle, and its velocity in vacuum is the universal velocity of light
The problem is to find out how photons are produced. Photons generally release energy due to the electron transition outside the nucleus, and the energy is released in the form of photons. Photons gain mass because of energy. This ratio is the square of the speed of light, which is the famous mass energy equation

On Maxwell's invariance theorem of light speed
Einstein said: "suppose I catch up with another beam of light at the speed of light, and this beam of light is reflected from a clock, then I will see a still clock face. In other people's eyes, the clock is still ticking away..."
What I want to ask is that since Maxwell has proved that the speed of light does not change for any observer who moves at any time and place in any way, even if he can move at the speed of light, can he really catch up with that beam of light? And even if he can catch up, the light emitted from outside is still at the speed of light relative to his speed! Shouldn't he see a walking clock?

He can't catch up with the light because the speed is the same. But as long as his speed is the same as the speed of light, the clock face he sees belongs to the time when the reflected light is emitted. No matter where he moves (the direction of motion should be the same as that of the reflected light), as long as he can see the clock (I don't know how to see it?), the time of that clock is still

How to use Maxwell's equation in vacuum to deduce the speed of light

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Choose the appropriate coordinate system to simplify the problem, and finally make them all zero to get the speed of light C in vacuum

Does Maxwell's theory have anything to do with the constant speed of light?

Maxwell's equations show that the speed of light is only related to the dielectric constant and magnetic constant of matter, and has nothing to do with any reference object. Therefore, the principle of invariable speed of light means that the speed of light has nothing to do with the selection of reference object. When a train advances at the speed of light, the speed of any beam of light emitted from the ground he sees is the speed of light

If a person moves at the speed of light, then light is stationary. Does this contradict Maxwell's electromagnetic theory?

If a person moves at the speed of light, then light is stationary. Does this contradict Maxwell's electromagnetic theory? No, the speed of light seen by a person as a reference frame is zero
As for the speed of light, whether the speed of light is variable or not, I think it is variable. The reason is that when the light is powered on, the light will be on, indicating that there is photon radiation, and the photon is the speed of light. When the light is not powered on, the photon does not radiate, and the photon is zero speed. There will be an acceleration between the zero speed and the speed of light. In the process of acceleration, the speed of light changes, but the time is too short to be measured by modern instruments
If you move at the speed of light, the light you see is still at the speed of light, and the light you see can move at twice the speed of light?