Creation for Kids—The Sun: “The light that rules the day”
Published in Creation 43(1):32–35, 2021
The sun literally lights up the day! This star provides us with light as well as heat. It also powers green plants, allowing them to make their own food. Animals and people can eat plants for food. Without the sun there would be no light, heat, or food.
The sun is huge!
The sun may not look big, but it really is! How do we know? Because it’s so far away, it must be huge to look the way it does.
About 250 years before Christ, Aristarchus proved that the sun must be many times further away than the moon. So why do they seem to be the same size? Because the sun must be far bigger than the moon. In fact, far bigger than the earth!
Modern astronomers now know that the sun is about 150 million km (93 million miles) away. This distance is also called the astronomical unit (AU). The sun is over 100 times wider than the earth. It is 1,392,000 km (864,950 miles) across. It is so huge that 1.3 million Earths could fit inside it.
Our special star
The sun is remarkable even by the standards of stars. The sun is bigger than most stars, but that’s not what makes it the most important.
It is also very stable and has been for thousands of years. Every few years, the sun sends out a major flare that can interfere with city power grids. However, living creatures are not harmed. Other stars can send out flares that can be millions of times more powerful. That would kill all life on earth. Fortunately, these stars are so far away that they haven’t the slightest chance to hurt us.
The sun is just the right colour to support life on Earth. Many drawings of the sun show it to be yellow. But did you know that it’s actually white (see photograph)? People think the sun is yellow because they see it at sunset when it’s not so bright. But then the sunlight must go through more of the air (see illustration). This scatters some of the blue light. So the sunlight we see is yellow, and even orange and red—sunset.
It’s hard to imagine how powerful the sun is. Its light is so strong that you should not look at it directly, even through sunglasses. And never, ever look at it through binoculars or a telescope!
We measure power in watts (W). A bright lightbulb can use 100 W of electrical power. One trillion watts is a terawatt (TW). The total electrical power used by all people on Earth comes to about 15 TW.
The sun’s total power is about 400 trillion TW. But only about 200,000 TW reaches the earth. And only about half of that reaches the surface. This means that every square metre of Earth’s surface receives an average of 160 W during the day. We are at just the right distance from the sun to receive just the right amount of power. Not too much, and not too little.
The sun also produces a stream of very fast electrically charged particles called the solar wind. The Voyager space probes, launched in 1977, found that the wind was still ‘blowing’ way past all the planets. Voyager 2 recently discovered that this solar wind acts as a ‘shield’. Without it, cosmic rays would harm life on Earth.
How does the sun produce such enormous power? By a process called nuclear fusion. Hydrogen atom fuse together in the core of the sun to produce helium. This process releases a huge amount of energy. The surface is ‘only’ 5,470 °C (9,880 °F). The core, however, is an unimaginable 14 million °C (25 million °F).
The sun at the centre of the solar system
Because of the sun’s huge size, Aristarchus proposed that it was at the centre of our solar system. But most astronomers and scientists disagreed, because they couldn’t work out how the earth could move.
In fact, this wasn’t really solved until almost 2,000 years later. This was the work of the brilliant creationist scientist Sir Isaac Newton. His revolutionary laws of motion and law of gravity showed how and why the earth could orbit the sun. These are probably the most important laws in all of science.