An astronomical unit (AU) is a unit of length used primarily to measure distances within the solar system.

Copernican heliocentrism is a scientific model of the solar system proposed by Polish astronomer Nicolaus Copernicus in the 16th century.

Euclid is a historical figure known as the "Father of Geometry" and is believed to have lived around 300 BCE in ancient Greece.

The European Space Agency (ESA) is an intergovernmental organization dedicated to space exploration and scientific research.

Friedrich Wilhelm Bessel (22 July 1784 - 17 March 1846) was a German astronomer, mathematician, physicist, and geodesist.

Geometry is a branch of mathematics that deals with the properties, relationships, and shapes of figures and spaces.

Heliocentrism is a scientific model that places the Sun at the center of our solar system, with Earth and other planets revolving around it.

The Milky Way is a barred spiral galaxy that is part of the Local Group of galaxies, which also includes the Andromeda Galaxy, the Triangulum Galaxy, and about 54 other smaller galaxies.