How Does the Sun Produce Light?


The sun produces light because it produces energy; light is one form that the energy takes. The sun's energy comes from nuclear fusion reactions at its core, where the temperature is 13.6 million kelvins. This energy travels through the sun's internal layer to the surface, where the temperature is only 5,700 kelvins. From there it radiates into space as visible light.

Hydrogen-to-Helium Fusion

  • The main reaction occurring in the sun's core is the conversion of hydrogen to helium. Through a chain of reactions, four protons and four electrons -- basically four hydrogen atoms -- become a single helium atom with two protons and two neutrons. Approximately 0.7 percent of the mass of the hydrogen atoms gets converted to energy in the process, which is equivalent to 4.26 million metric tons per second.

From the Center of the Sun

  • The energy created by hydrogen-to-helium fusion propagates in the form of photons. Near the core, atoms quickly absorb these photons and convert their energy to kinetic energy, maintaining the high temperatures needed for fusion. The frequency of these collisions and the temperature decrease with increasing distance from the core, however, and at the photosphere, which is the sun's outer layer, some of the photons radiate into space. They are responsible for the light that humans see on Earth.


  • Photo Credit AlinaMD/iStock/Getty Images
Promoted By Zergnet



You May Also Like

  • How Does the Sun Affect Plants?

    The sun has an extremely important effect on plants. In fact, they cannot live without it, since they use the energy from...

  • How is Ultraviolet Light Produced?

    Scientists produce ultraviolet light in the lab by making different types of fluorescent light bulbs. An electrical current excites mercury vapor mixed...

  • How Does Photosynthesis Help the Plant?

    A baby plant uses energy stored in the seed to grow. Once the energy from the seed is all used up, the...

  • Lightbulbs That Mimic Sunlight

    Spending too much time indoors under dull lighting can affect your mood, energy level and productivity. Studies have shown that people who...

  • How Does a Firefly Produce Light?

    A firefly produces light by taking advantage of a chemical reaction in which luciferin combines with oxygen in the presence of luciferase...

  • How Heat Can Produce Electricity

    Heat can be used to produce electricity by creating steam when combined with different fuels. Find out how different power stations can...

  • How Does the Earth Receive Heat From the Sun?

    When heat comes to Earth from the sun, various forms of radiation are absorbed in the atmosphere and converted into infrared radiation....

  • How Does the Sun Work?

    The sun is a star, which is a ball of burning gas that stays as it is through thermonuclear reactions. Learn about...

  • How Fast Does Light Travel?

    Light is a form of electromagnetic radiation, which always travels at a speed of 186,000 miles per second in a vacuum. Discover...

Related Searches

Check It Out

How to Build and Grow a Salad Garden On Your Balcony

Is DIY in your DNA? Become part of our maker community.
Submit Your Work!