What are the properties of the sun


The sun is about 4.57 billion years old and makes up about 99.9% of the total mass of our planetary system. It consists for the most part of hydrogen and helium and forms the center of our planetary system. The processes of the climate and life on earth are driven by solar energy. About a third of the tides are also caused by the effects of gravity from the sun.


Diameter:1,3914 × 106 km
Dimensions:1,989 × 1030 kg
Medium density:1.408 g / cm3
Luminosity:3,846 × 1026 W.
Surface temperature:5778 K
Main Ingredients:73.5% hydrogen
25% helium
1.5% heavy elements



It makes up about 25% of the solar radius. At around 15 million degrees Celsius, all of the sun's energy is released here in a nuclear fusion reaction. Hydrogen nuclei fuse to form helium, releasing high-energy gamma photons. Around four tons of matter are converted into pure energy every second.

Radiation zone:

The radiation zone extends over 60-70% of the solar radius. When the particles of the plasma collide, the gamma photons from the nucleus are converted into longer-wave X-ray photons. The constant absorption and emission of photons causes them to move very slowly towards the surface of the sun. It can take 10,000 to 170,000 years before it gets there.

Convection zone:

About 20% of the sun's radius is taken up by the convection zone. The energy from the inside of the sun is transported to the outside by convection currents. Hot plasma rises, cools down on the surface of the sun and then sinks back down. The upper part of these streams is visible as granules. Such granules cover the entire surface of the sun.


It is considered the surface of the sun and is 300-400 km thick. The solar energy is released into the environment here. In the meantime, the photons have lost their high energy and are mainly released as visible light.


The chromosphere extends from 10,000 to 30,000 km. Its density is less than that of the photosphere, but its temperature rises to around 10,000 K.


It is the outermost shell of the sun and extends over several solar radii into space. At a few hundred kilometers above sea level, their temperature suddenly rises to up to two million degrees Celsius. The reasons for this are still unclear. However, such heating is only possible due to the extremely low density of the corona. During a total solar eclipse, the corona can be observed with the naked eye, as can be seen in the following picture.

Sunspots and prominences:

The sun has a very strong magnetic field. Irregularities in this field are visible through the so-called sunspots on the sun's surface. These are areas that are around 2000 degrees Celsius cooler in relation to their surroundings and therefore appear as dark areas. Magnetic arcs are created between these sunspots that carry ionized gas with them. These flows of matter - called protuberances - can protrude several hundred thousand kilometers into space.

Earth and sun in size comparison:

The sun on Wikipedia
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