For five billion years, the sun has been shining from the sky and making the earth life-friendly. But how is it that the sun can shine at all?
Munich – The sun, the center of our solar system with its eight planets, plays a crucial role in life on Earth. Not only does it provide heat, which allows the presence of liquid water, but its light also allows photosynthesis in plants. But how can the sun actually shine?
The sun itself is a gigantic ball consisting mainly of hydrogen and helium. There are enormous pressures inside the sun that cause hydrogen atoms to fuse together and become helium nuclei - a process called nuclear fusion. The fusion of four hydrogen nuclei produces a helium nucleus as well as energy. This energy is radiated in the form of light and heat and eventually reaches the earth, creating conditions conducive to life.
Sun fuses hydrogen to helium and shines
For five billion years, the sun has fused hydrogen into helium, emitting light and heat into space. But there is another significance of the sun for life on earth. Research has shown that intense eruptions from the sun in the past may even have affected the development of life on our planet. Particles from the sun may have stimulated the formation of amino acids, which are considered the basic building blocks of life.
The sun will shine for another five billion years
The sun will be able to provide energy and heat for another five billion years before its "fuel" runs out. But long before this happens, the sun will change. In less than a billion years, the sun's rising temperatures will cause the oceans on Earth to evaporate. Eventually, the sun will turn into a red giant, greatly inflating in the process. During this process, it will engulf the planets Mercury and Venus, possibly burning the Earth.
In the end, the sun will collapse into a tiny white dwarf and our solar system will be history. But until then, the sun will continue to radiate its radiance and warmth into space, promoting life on Earth.
This article, written by the editors, used machine support. The article was carefully reviewed by editor Tanja Banner before publication.