The sun is situated at the center of the solar system and whilst it may share many similar characteristics with other stars, it is far brighter when we view it from Earth due to its close proximity, comparatively.
The sun is primarily formed from hydrogen and helium plasma with matter that has been constructed from ionized gases. The sun is far larger than any of the surrounding planets and its entire mass includes approximately 99.8 percent of the mass continued within the entire solar system.
As a result of this, it exerts an incredibly powerful gravitational force that maintains the gravitational pull and orbits of individual planets, asteroids and comets.
The sun’s heat and light provides the vast majority of Earth’s energy and nearly every single living organism will absorb energy from the sun. It was reverted for it’s powerful significance in early societies and has been worshipped for centuries. In old Germanic languages, it was described using terms such as “sunna” or “sunno” and the English word ‘sun’ derives specifically from the old English word “sunne”.
Stars are born from space dust and gases that make up interstellar formations called nebulas. As a result of gravitational pull, a nebula’s gases will condense into a globular collection of dust and gas and this fusion starts when the temperature rises to above 72 million degrees Fahrenheit as this releases a large amount of energy.
The infant star lights up and during the nuclear fusion, smaller light nuclei combine to form larger nuclei. The sun’s core fusion of hydrogen nuclei results in the formation of helium nuclei that contain two protons. The entire process produces a humongous amount of electromagnetic energy and heat and this is why the sun is such a vastly powerful entity in our solar system.
How Hot Is It?
The sun is made up of multifaceted layers and the temperature of each layer depends on which aspect that you are referring to. The heat contained within the sun can vary by millions of degrees between different aspects of the star.
The core of the sun is approximately 27 million degrees Fahrenheit and is the hottest part of the star. In the sun’s core, hydrogen atoms fuse together under a monumental amount of pressure in order to create helium. This nuclear fusion then releases a vast amount of heat and radiation and photons carry this energy outwards.
The radiative zone lies just outside of the sun’s core. In this zone, temperatures will decrease to approximately 4 million Fahrenheit as the photons that are carrying energy from the sun’s core are absorbed by other particles. The indirect route taken by these photons slows them down which reduces the levels of direct transmission. In fact, photons can stay in the radiative zone for thousands of years prior to reaching the sun’s surface.
The convection zone is a region of the sun that extends for an incredible 120,000 miles. This is the middle layer of the sun and temperatures are approximately 4 million degrees Fahrenheit.
Similarly to the motion of boiling water, plasma within this layer will move in a continually convective manner and these connective cells will then transport heat and radiation outwards towards the sun’s surface. At the top of this zone, there is also a region of ‘subsurface flow’ that separates the sun’s interior and exterior surface.
The photosphere is the sun’s outer surface and it emits light and heat towards earth and the surrounding planets. This is the layer that can be physically observed from earth and whilst it is the coolest area of the sun, the temperature is still approximately 10,500 degrees Fahrenheit.
The chromosphere lies directly above the photosphere and it is the thin atmospheric layer that surrounds the sun. During an eclipse, the chromosphere’s reddish tint can be witnessed from Earth and despite the chromosphere’s distance from the sun’s core, it’s temperature is actually slightly higher than the photosphere and sits at approximately 11,100 degrees Fahrenheit.
The corona is the thickest layer of the sun, irrespective of the fact that it is the least dense. Similarly to the chromosphere, the corona can only be observed through solar eclipses and its shape is dependent on sunspot activity. A corona eventually fades into a stream of protons and electrons that is otherwise known as a solar wind.
This wind permeates the entire solar system and can reach approximately 1.8 million degrees Fahrenheit. The particles that make up these solar winds are deflected by the earth’s magnetic field in order to ensure that the vast majority of these particles do not reach the Earth’s surface.
The structure of the sun is fascinating and its sheer size allows for a variety of temperatures to be measured within its vast structure. The reason that the sun is rounded is because it is formed and collapses under the force of its own gravity and as material collapses on itself, a sphere shape is the most efficient shape that can be formed.
Gravity is renowned for being able to pull material towards the centered mass of an object but due to the rotary effect of the sun, it is not technically a perfect sphere as it widens at its equator.
To conclude, the sun’s temperature depends on which part of the star you are referring to. Whilst it’s core is undoubtedly the hottest part of this star and has a temperature of approximately 27 million degrees, the outer layers of the sun are approximately 10,500 degrees Fahrenheit.
This contrast alone illustrates just how large the sun is and the sheer amount of energy that is produced and expelled from its inner core is monumental. The photons can become slowed down during their transmission from the sun’s core to it’s photospheric layer and this causes a reduction in temperature.
It can also take these photons thousands of years to travel from the core to the outer layers of the sun. The solar winds that are formed by the corona are also incredibly hot with a temperature of 1.8 million degrees Fahrenheit and thus, the sun’s core is not the only aspect that expels exponential heat.
Without the sun, we would not have enough light or heat to survive on Earth and we should also recognize that it is the Earth’s magnetic fields that prevent solar wind particles from reaching the Earth’s surface.
Therefore, looking after our own planet is key to ensuring that we are respecting the magnificence and sheer power of this star without overlooking the potentially disastrous effects that it could reap upon the surface of the Earth.
The heat that is generated by the sun is not only key to energizing our own planet but it is also imperative to providing energy for the entire solar system and it is important to note that its mass equates to over 99% of the solar system itself which explains why it generates such an abundant supply of heat and light.