O Sun and the star closest to Earth, is approximately 150 million kilometers from us, and is responsible for keeping the entire Solar System in its interactiongravitational: eight planets and the other celestial bodies that compose it, such as dwarf planets, asteroids and comets.
Lookalso: Solar System - origin, planets, stars, curiosities
Sun Characteristics
The composition of the Sun is of 74% in hydrogen and 24% in helium, with the remaining percentage formed mainly by oxygen, carbon and iron. All the energyproduced by the Sun comes from the process of Nuclear fusion due to the high temperatures of its core (about 15 million kelvin) and its enormous pressure.
Consequently, our star is able to convert atoms from hydrogen in helium, and the numbers are incredible: every second, the Sun fuses about 600 million tons of hydrogen into helium, converting part of that mass into energy, in the form of electromagnetic waves, like the gamma.
Altogether, the sun consumes about 4 million tons of its mass per second, a rate more than enough to keep it shining for the next 6 or 7 billion years, due to its
greatpasta, which is approximately 1.98.1031 kg, more than 330,000 times the mass of the Earth.Due to its enormous mass, the gravity on the surface of the Sun reaches 274 m/s², 27.4 times larger than the Earth's mass. This makes the exhaust speed there reach 617 km/s, more than 2 million kilometers per hour.
the period of rotation of the sun around its own axis is 27days for your Ecuador, that turns the 7189 km/h, and from 35days for your poles. This difference in rotational period produces a differential rotation (called a solar dynamo), responsible for its large magnetic activity, since all the matter present in the star is ionized (in the plasmatic state), giving rise to the stormssolar, eruptionscoronaries and stainssolar.
readalso: What is nuclear fission?
physical structure of the sun
The Sun can be divided into parts with different physical properties, see which they are:
- Core: where nuclear fusions occur, and the nucleosynthesis process represents about 25% of the Sun's mass.
- Radiative zone: where the electromagnetic radiation produced by the nucleus is reflected many times, and it takes thousands of years to escape from its interior.
- Convective zone: an unstable layer that transmits heat through convection, solar eruptions occur in this region.
- Photosphere: the outermost layer of the Sun, it is on this basis that all sunlight is radiated. The photosphere is about 100 km thick.
- Chromosphere: a low-density layer that marks the transition between the solar atmosphere and the solar corona.
- Crown: an aura of plasma that permeates millions of kilometers around the Sun, its temperature can reach 1,000,000 ºC. This temperature is believed to arise because of the Sun's intense magnetic field.
sun age
It is estimated that the age of the Sun is 4.6 billion years and that, in about 7 billion years, he will be a red giant, with an equatorial radius 200 times greater than the current one (of 6,963.108 m, almost 109 times the radius of the Earth) and up to 5000 times brighter, “swallowing” our planet's orbit.
Upon reaching this mark, the Sun will be able to fuse atoms of carbon due to high temperatures. The final stages of the Sun's stellar evolution indicate that this star will become a a-N-AWhite - a class of stars extremelydense — presenting less than half of its current mass due to the process of nuclear fusion and the emission of solar winds, compressed into a radius until 17 times smaller, leaving a large cloud of stardust around it.
color of the sun
The sun is considered a star of main sequence (which produces its energy through the fusion of hydrogen), of category a-N-AYellow. Despite the name, it's not a small or yellowish star, it's actually bigger and brighter than a good one. part of the stars visible to the naked eye, despite being very far from being one of the largest, or more luminous.
the adjective Yellow, in turn, it is related to its surface temperature (about 6000 ºC) and its luminosity: this is a very star morecold and any lessluminous that white and blue calls.
Furthermore, the sun is capable of producing allyoulengthsinwave of visible light, so that when viewed from outside the Earth, its color is White. The yellow tone that we observe when looking at this star appears due to the scattering of the sun's rays as they enter the atmosphere, see the photo below, taken at 22 km high.
Sun temperature
The temperature of the Sun is quite varied and can be quite complex to understand, due to the large number of concepts involved in explaining it. O coresolar can reach 15 million kelvin, it is in this region where the helium atoms are formed through the Fusionnuclear. The region immediately near the nucleus, known as the zoneradioactive, may have temperatures ranging between 2 and 7 million kelvin.
On the margins of the radioactive zone, is the zoneconvective, where large currents of plasma which are capable of transmitting energy to the outside of the Sun through convection. The convective zone has an average temperature of 2 million kelvin. The surface of the Sun, in turn, called the photosphere, has an average temperature of 5778 by kelvin.
See too: Five fun facts about the Solar System
Solar radiation
The energy produced by the Sun partially reaches Earth in the form of waveselectromagnetic. On the earth's surface, the solar radiation intensity arrives at 1366 kW/m² (kilowatts per square meter), and this value varies by less than 0.1 percent over the entire orbital period. All this energy comes from nuclear fusions that take place in the Sun's nucleus and are capable of converting hydrogen atoms into helium atoms.
During the fusion process, about 0.7% of the mass of the hydrogen atoms is transformed into energy, according to the famous physicist's equation. Albert Einstein: E = mc². Using this formula, we can estimate that each nuclear fusion is capable of releasing up to 6.8 megaelectron volts (MeV).
About 1.3% of all the energy that is produced by the Sun is in the form of tiny particles called neutrinos. You neutrinos they are so small that they are able to traverse the interior of our planet without touching a single atom. The Sun emits a huge amount of these particles, to give you an idea, here on Earth we are exposed to a flow of 8.1010 neutrinos per square centimeter, every second.
As we already know, much of the remaining energy that is produced by the Sun is emitted in the form of electromagnetic waves. You photonsinlight that are created in the solar core can only reach its surface after a period of approximately 170,000 years. This happens because of the high density inside the Sun, therefore, when we look at the star, the light that reaches our eyes was produced at least 170 thousand years ago. After leaving the Sun, light takes just over eight minutes to reach Earth.
Read more: History of astronomy - the evolution of this science
solar wind
in addition to electromagnetic waves and from the neutrinos, the Sun ejects a large amount of hydrogen and helium ions, giving rise to what we call the windsolar. the solar wind is a plasmaheated which can travel at speeds of up to 900 km/s. The temperature of the solar wind can reach up to 1 million degrees Celsius. Near Earth, its temperature is about 200,000 K.
The solar wind propagates through the interplanetary medium, along a complex trajectoryspiral, guided by the intense magnetic field produced by the Sun. Their high speed means that these particles reach Jupiter in approximately 27 days, the same period it takes the Sun to complete a revolution around its own axis.
When solar wind particles meet the fieldmagneticterrestrial, they are accelerated and spiral towards the Earth's magnetic poles. The excitation caused by friction between the particles of the solar wind and the atmosphere results in the emission of visible light, popularly known as Aurorapolar.
It is estimated that the Sun's magnetic influence extends between 84 and 94 astronomical units, at these distances, it is still possible to detect the presence of the solar wind and the influence of the Sun's magnetic field. The astronomical unit, in turn, is equivalent to the distance between the Earth and the Sun, that is, approximately 150 million kilometers. For comparison purposes, the planet Neptune is located 30 astronomical units from the Sun.
evolution of the sun
The Sun is "burning" hydrogen to at least 4.6 billion years. Some physical models indicate that the star is up to 10% brighter every billion years, so today's sun is about 40% brighter than it was at the time of its creation.
O futureofSun will be marked by the moment when all of its hydrogen is converted to helium. When this happens, it will have its size increased by up to 200 times, reaching the orbit of Venus.
At the Final of your life, the sun will suffer a huge collapsegravitational, its size will be reduced until it changes into a white dwarf star. Astronomers estimate that, at this stage, the Sun will have about 50% of your current mass and that its size is comparable to the Earth's.
By Me. Rafael Helerbrock