What is the distance from the Earth to the Sun?

Earth and neighbor planets, along with asteroids, dwarf planets, meteorites, comets . belong to the solar system (solar system) with the Sun at the center of this system. Astronomers use a measurement unit to measure the distance between celestial bodies in the solar system, called the AU (Astronomical Unit) , or the Vietnamese word for Astronomical Unit .

The distance from the Earth to the Sun is 149,597,870,700 meters (149.6 million km).

Astronomical unit (AU) is the distance from the Earth to the Sun. An astronomical unit equals the distance from the Earth to the Sun, which is 149,597,870,700 meters (149.6 million km). Astronomers use this unit to measure the distance between celestial bodies in the solar system. For example, the distance from the Sun to Jupiter is 5.2 AU while Neptune is 30,07 AU from the Sun.

However, as you know, Earth's orbit around the Sun is not an absolute perfect circle, it is an ellipse. So for a year, sometimes the Earth comes close to the Sun, sometimes away.

The point on the Earth's orbit closest to the Sun is called the Near Point , a distance of about 146 million kilometers and in January every year the Earth will reach this point. The point in orbit that the Earth is farthest away from the Sun is called the Point of Fury , about 152 million kilometers away and in July every year the Earth will reach this point.

Picture 1 of What is the distance from the Earth to the Sun?
Astronomical unit (AU) is the distance from the Earth to the Sun.

Historically recorded, Aristarchus astronomer and mathematician of the Greek island of Samos was the first to measure the distance from the Earth to the Sun around 250 BC. And in modern times, Dutch astronomer Christiaan Huygens measured the distance from the Earth to the Sun in 1653.

Mr. Huygens uses the phases of Venus to search for corners in the Venus - Earth - Sun triangle. For example, when Venus appears halfway through the Sun, three celestial bodies form an equilateral triangle seen from the Earth. Guessing the size of Venus (accidentally but accurately), Mr. Huygens was able to determine the distance from Venus to Earth, and when he knew the distance, plus the angles of the triangle, he was able to measure the distance to the Sun. However, because Huygens's method is partly a speculative product and not entirely based on scientific grounds, it is not trusted.

In 1672 the Italian mathematician and astronomer Giovanni Cassini used a method that included parallax, or angle error, to find the distance to Mars and at the same time calculate the distance to the Sun. He sent a colleague, Jean Richer, to French Guiana while he himself was in Paris. They measured the relative position of Mars with other stars and triangulated these measurements with a known distance between Paris and Guiana. Once they grasp the distance to Mars, they can also calculate the distance to the Sun. Because Cassini's methods are more scientific, they are trusted.

In August 2012, the International Astronomical Association (IAU) officially confirmed the number 149,597,870,700 meters for each Astronomical Unit. This number is based on the speed of light, a defined distance. One meter is defined as the distance that light travels in a vacuum in a fraction of 299,792,458 seconds.