The Sun (known in Latin as Sol) is the star located at the center of our Solar System and is the primary source of life on Earth. It plays a decisive role in shaping the climate and weather conditions of our planet.
The Sun is almost perfectly spherical in shape. The difference between its polar and equatorial diameter is only about 10 kilometers. Its average radius is approximately 695,508 km — which is about 109 times larger than Earth’s radius. Roughly 20–25% of the Sun’s radius consists of its core.
The Size and Structure of the Sun
The Sun is composed primarily of hydrogen (about 70%) and helium (about 28%).
It is classified as a main-sequence G2V star and is commonly referred to as a “yellow dwarf.”
The Sun’s mass is approximately 330,000 times greater than the mass of Earth.
It contains 99.86% of the total mass of the Solar System.
The Sun’s surface area is about 11,990 times larger than Earth’s surface area.
Approximately 1 million Earths could fit inside the Sun (if it were hollow, about 1.3 million Earths could fit).
The average distance between the Earth and the Sun is called one Astronomical Unit (AU), which is approximately 150 million kilometers.
Temperature and Energy
The temperature in the Sun’s core reaches about 15 million degrees Celsius.
The surface temperature of the Sun is approximately 5,600°C.
Energy in the Sun is produced through the process of nuclear fusion — hydrogen atoms are converted into helium.
It takes sunlight about 8 minutes and 20 seconds to reach Earth.
Interestingly, while light reaches Earth in minutes, energy takes millions of years to travel from the Sun’s core to its surface.
The Motion of the Sun
The Sun is located about 24,000–26,000 light-years away from the center of the galaxy.
It orbits the center of the Milky Way at a speed of approximately 220 kilometers per second.
It takes the Sun about 225–250 million years to complete one orbit around the galactic center.
Because Earth moves around the Sun in an elliptical orbit, the distance between them varies during the year between 147 and 152 million kilometers.
The Sun’s Magnetic Field and Sunspots
The Sun has a very powerful magnetic field. Sudden releases of magnetic energy result in:
Solar flares
Magnetic storms
Sunspots
Sunspots are formed due to the twisting of magnetic field lines and are associated with intense magnetic activity, somewhat comparable to tornado-like magnetic phenomena on Earth.
Solar Wind
The Sun continuously emits a stream of charged particles known as the solar wind.
The solar wind travels at a speed of approximately 450 kilometers per second.
This stream is produced as a result of the Sun’s magnetic field extending into space.
When solar wind interacts with Earth’s magnetic field, it creates the northern and southern lights (auroras).
The Future of the Sun
The Sun is approximately 4.6 billion years old and has already used about half of its hydrogen fuel.
In about 5 billion years, it will enter the red giant phase.
During this stage, it will expand enough to engulf Mercury, Venus, and possibly Earth.
Afterward, the Sun will shed its outer layers and become a white dwarf star.
Conclusion
The Sun is not just an ordinary star. It:
Is the main source of energy in the Solar System
Played a crucial role in the formation of the planets
Ensures the existence of life on Earth
Studying the Sun helps us better understand the cosmos and the origin of life itself.