1.3 million times

The Sun’s diameter is about 109 times that of Earth, but since volume scales with the cube of the diameter, it works out to roughly 1.3 million times Earth’s volume. This means the Sun is large enough to fit about 1,300,000 Earths inside.

Solar flare

The explosive phenomena that occur on the Sun’s surface are called solar flares. They arise when magnetic reconnection releases enormous amounts of energy and are observed as plasma ejections and intense radiation. Solar flares occur frequently during periods of heightened solar activity and can, in some cases, affect Earth’s communication networks.

about 10 billion years

The Sun was born about 4.6 billion years ago, and its lifespan as a main-sequence star is estimated to be about 10 billion years. Therefore, the Sun has spent roughly half of its total lifetime and is estimated to have about 5 billion years remaining. After this period, the Sun will evolve into a red giant and is ultimately predicted to become a white dwarf.

About 8 minutes and 20 seconds

It takes about 8 minutes and 20 seconds for sunlight to reach Earth. Since the speed of light is approximately 300,000 kilometers per second and the average distance between the Sun and Earth is about 150 million kilometers, light needs roughly 500 seconds—about 8 minutes and 20 seconds—to travel that distance.

Option 2

The surface temperature of the Sun is estimated to be about 5,500°C. This value is calculated based on the assumption that the Sun emits blackbody radiation and refers to the temperature of the outermost layer called the photosphere. The core of the Sun is much hotter, estimated to reach around 16 million°C.

hydrogen

The Sun is composed of about 75% hydrogen by mass and about 25% helium. All other elements together account for less than 1%. Inside the Sun, hydrogen undergoes nuclear fusion, releasing energy as it is converted into helium.

about 4.6 billion years

The solar system and the Sun were formed about 4.6 billion years ago. This estimate is inferred from data collected from the Sun and nearby celestial bodies, as well as theoretical insights into star and planet formation. Therefore, the correct answer is “about 4.6 billion years.”

nuclear fusion reaction

What occurs at the Sun’s core is nuclear fusion. In this process, hydrogen nuclei (protons) fuse under extremely high temperatures and pressures to form helium nuclei. Enormous amounts of energy are released in the process, which serve as the source of the Sun’s light and heat.

total solar eclipse

There are different types of solar eclipses, such as partial, total, and annular. When the Moon completely covers the Sun, it is called a total solar eclipse. An annular solar eclipse refers to a situation where the Moon appears slightly smaller, so only the outer edge of the Sun is visible and it is not completely covered.

lower than the surroundings

The surface temperature of the Sun is about 5,500 K, while sunspots are about 3,500–4,500 K. This means they are roughly 1,500 K cooler than their surroundings. Sunspots appear darker than the surrounding areas because this temperature difference causes them to emit less light.