WHY? The time it takes for light to travel from the core of the Sun to its surface, spanning over 20,000 years, stands in stark contrast to the mere 8 minutes it takes for light to reach the surface of the Earth.

 

The time it takes for light to travel from the core of the Sun to its surface, spanning over 20,000 years, stands in stark contrast to the mere 8 minutes it takes for light to reach the surface of the Earth.

Credit Image Nasa Editing By Arabian Space Science

The Sun is an enormous ball of plasma that generates both light and heat through a process called nuclear fusion.

 1. When hydrogen atoms come together to form helium atoms through nuclear fusion, an immense amount of energy is released.

2. Through the process of nuclear fusion, hydrogen atoms combine and transform into helium atoms, resulting in the release of an enormous amount of energy.

3. The combination of hydrogen atoms to create helium atoms during nuclear fusion leads to the release of a tremendous amount of energy.

 

However, the journey of these photons from the Sun's core to its surface is not a smooth one. The core of the Sun is incredibly dense and hot, reaching temperatures of around 15 million degrees Celsius. As the photons travel through the plasma, they collide with atoms and molecules, causing them to scatter in various directions. This results in a long and unpredictable path, similar to a meandering walk taken by someone who has had a bit too much to drink. It can take these photons tens of thousands of years to finally reach the surface of the Sun.

 

The surface of the Sun, known as the photosphere, is much cooler and less dense compared to the core, with temperatures of approximately 5,500 degrees Celsius. Here, the photons can escape more easily and travel in a straight line towards the Earth and other planets. The distance between the Sun and the Earth is roughly 150 million kilometers, which is also referred to as one astronomical unit (AU). It takes about eight minutes and 20 seconds for light to cover this distance.

 

Therefore, it takes significantly longer for light to travel from the core of the Sun to its surface compared to the time it takes for light to reach the Earth from the Sun's surface. This is due to the fact that light travels much faster in empty space than it does in dense plasma. In a vacuum, the speed of light is approximately 300,000 kilometers per second, but it can be slowed down when it interacts with matter. The light we see from the Sun today was actually generated thousands of years ago within its core.