(ORDO NEWS) — The sun is at the center of the solar system, where it is the largest object. It contains 99.8% of the mass of the solar system and is about 109 times the diameter of the Earth – about one million Earths can fit inside the Sun.
The surface of the Sun has a temperature of about 5,500 degrees Celsius, and the temperature in the core reaches over 5 million C due to nuclear reactions. According to NASA, 100 billion tons of dynamite must be blown up every second to match the energy produced by the Sun.
How did the sun appear?
The sun was born about 4.6 billion years ago. Many scientists believe that the Sun and the rest of the solar system formed from a giant swirling cloud of gas and dust known as the Solar Nebula.
When the nebula collapsed due to gravity, it rotated faster and flattened into a disk. Much of the material was pulled toward the center to form the Sun.
The Sun has enough nuclear fuel to remain as it is for another 5 billion years. After that, it will swell and become a red giant.
Eventually, it will shed its outer layers and the remaining core will collapse and become a white dwarf. Slowly, the white dwarf will disappear and enter its final phase as a dim, cool theoretical object, sometimes known as a black dwarf.
The internal structure and atmosphere of the Sun
The sun and the atmosphere of the sun are divided into several zones and layers. The inner space of the Sun consists of the core, the radiation zone and the convective zone. The solar atmosphere above it consists of the photosphere, chromosphere, transition region, and corona. Behind this is the solar wind, the flow of gas from the corona.
The core extends from the center of the Sun about a quarter to its surface. Although it only makes up about 2% of the Sun’s volume, it is nearly 15 times as dense as lead and contains nearly half the Sun’s mass.
Next comes the radiation zone, which extends from the core to 70% of the way to the surface of the Sun, accounting for 32% of the Sun’s volume and 48% of its mass. Light from the core scatters in this zone, so it can often take a million years for a single photon to travel through.
The convection zone reaches the surface of the Sun and makes up 66% of the Sun’s volume, but only slightly more than 2% of its mass. This zone is dominated by seething “convection cells” of gas.
There are two main types of solar convection cells – granulation cells with a width of about 1000 kilometers and supergranulation cells with a diameter of about 30,000 km.
The photosphere is the lowest layer of the sun’s atmosphere that emits the light we see. It is about 500 km thick, although most of the light comes from its lower third.
Temperatures in the photosphere range from 6125 C at the bottom to 4125 C at the top. Next comes the chromosphere, which is hotter, up to 19,725 C, and appears to be composed entirely of spiky structures known as spicules. They are usually about 10,000 km high.
After that, there is a transition region several hundred to several thousand kilometers thick, which is heated by the corona above it and emits most of its light in the form of ultraviolet rays.
At the top is a superhot corona made up of structures such as loops and streams of ionized gas. Corona temperatures typically range from 500,000 C to 6 million C and can even reach tens of millions of degrees when a solar flare occurs. The material of the corona is blown away by the solar wind.
Sun’s magnetic field
The Sun’s magnetic field is typically about twice as strong as the Earth’s magnetic field. However, in small areas it is highly concentrated, reaching 3000 times more strength than usual.
These kinks and swirls in the magnetic field occur because the Sun rotates faster at the equator than at higher latitudes, and because the Sun’s interior rotates faster than the surface.
These distortions create elements ranging from sunspots to spectacular eruptions known as flares and coronal mass ejections.
Flares are the most violent eruptions in the solar system, while coronal mass ejections are less violent but involve an extraordinary amount of matter. A single ejection can release approximately 20 billion tons (18 billion metric tons) of matter into space.
Sunspots and solar cycles
Sunspots are relatively cool dark formations on the surface of the Sun that are often roughly circular in shape. They appear where dense beams of magnetic field lines from the interior of the Sun break through the surface.
The number of sunspots varies with solar magnetic activity – the change in this number from a minimum of zero to a maximum of about 250 sunspots or sunspot clusters, and then back to a minimum is known as a solar cycle and averages about 11 years. At the end of the cycle, the magnetic field rapidly changes polarity.
—
Online:
Contact us: [email protected]
Our Standards, Terms of Use: Standard Terms And Conditions.