Ancient rockets first appeared in the Three Kingdoms period. They put torches in arrows and then launched them. Later, ancient China invented gunpowder and began to use it in wars in the late Tang Dynasty. In the Northern Song Dynasty, the earliest and most primitive "gunpowder" appeared in human history. "Gunpowder Arrow"

Some scholars have verified that the first person in the world who wanted to use a rocket to fly into the sky was Wan Hu, who made an important contribution to the entire process of mankind's exploration into the unknown world.

The geocentric theory, also known as the geocentric theory, was proposed by Ptolemy. It was systematized in the 2nd century AD and is the corresponding theory of the geocentric theory. This theory is a geocentric theory that believes that the earth is at the center of the universe, and humans live in the center of a hemispherical world. From around the 13th century to the 17th century, geocentric theory has been the world view recognized by the Catholic Church.

The heliocentric theory, also known as the seismic theory, was proposed by Copernicus. It is a theory about the movement of celestial bodies that is opposite to the geocentric theory. It believes that the sun is the center of the universe, not the earth.

The three laws proposed by Kepler are also known as the law of ellipses, the law of area and the law of harmonics.

Newton used the laws of planetary motion to propose the law of universal gravitation

Proposed by Leibczny

The Apollo program (English: Apollo program) was a series of manned lunar landing missions organized and implemented by the United States from 1961 to 1972. The purpose is to realize manned lunar landing flights and field inspections of the moon, and to make technical preparations for manned planetary flights and exploration. It is an epoch-making achievement in the world's aerospace history.

Gravitational waves detected for the first time

It opens a new journey for mankind to explore the origin of the universe and curved space.

Chang'e 4 (Chang'e 4) is a lunar probe launched in the second phase of China's lunar exploration project. It is also the first human probe to land on the far side of the moon. It has achieved mankind's first soft landing and patrol survey on the far side of the moon, which is of great significance. The impact is far-reaching.