When the sun came up approximately. How old is the Sun? Can the Sun cool down? Sequence of solar evolution
SUN OPTION 1
1. According to modern scientific data, the age of the Sun is...
A) 2 billion years
B) 5 billion years +
B) 500 billion years
D) 300 billion years
2. What is the name of the line on the disk of a planet or satellite that separates the illuminated (daytime) hemisphere from the dark (nighttime) hemisphere.
A) Almucantrat
B) Parallax
B) Terminator +
D) Fakula
3. The most common element in the Sun is
B) hydrogen +
D) this question does not make sense, since the Sun is plasma
4. What is the name of the stream of mega-ionized particles (mainly helium-hydrogen plasma) flowing from the solar corona at a speed of 300-1200 km/ cinto the surrounding outer space?
A) prominences
B) cosmic rays
B) solar wind +
5. What spectral class does the Sun belong to?
6. In what part of the Sun do thermonuclear reactions occur?
A) in the nucleus +
B) in the photosphere
B) in prominences
7. An eclipse of the Sun is coming for the observer
A) if the Moon falls into the shadow of the Earth
B) if the Earth is between the Sun and the Moon
C) if the Moon is between the Sun and Earth +
D) there is no correct answer
8. Which layer of the Sun is the main source of visible radiation?
A) Chromosphere
B) Photosphere +
B) Solar corona
9. Which star is closest to the Sun?
A) Arcturus
B) Alpha Centauri
B) Betelgeuse
D) Proxima Centauri +
10.What is the temperature of the sun's surface?
D)15 000 000 0 C
Option 2
SUN
1.The closest star to Earth is
A) Venus, since ancient times called the “morning star”
B) Sun +
B) Alpha Centauri
D) Polaris
2.What two gases does the Sun mainly consist of?
A) oxygen
B) helium +
D) hydrogen +
3. What is the temperature of the surface of the Sun?
a)2800 degrees Celsius
b) 5800 degrees Celsius
c)10000 degrees Celsius
d) 15 million degrees Celsius
4.Solar energy is the result
a) thermonuclear fusion +
b) combustion
5. The outer radiating surface of the Sun is called
A) photosphere +
B) atmosphere
B) chromosphere
6. Photosynthesis is possible due to the presence in plant cells
A) glucose
b) chlorophyll +
c) carbon dioxide
D) oxygen
7. What explains the movement of the Earth around the Sun?
a) by the action of centrifugal force +
b) the action of inertia force
c) by the action of surface tension
d) the action of elastic force
8. According to modern views on the origin of the Sun and the solar system, they were formed from
a) Other stars and planets
b) Big Bang
c) gas and dust cloud +
9. The sun came on approximately
A) 100 million years ago
B) 1 billion years ago
B) 4.5 billion years ago +
D) 100 billion years ago
10. In the process of aging, the Sun will turn into
a) into a blue dwarf
b) into a red dwarf
c) into a red giant +
d) into a blue giant
Option 3
What proportion of the total mass of the solar system is contained in the sun?
What is "solar wind"?
Flow of ionized particles extending to the boundaries of the heliosphere
The last outer shell of the Sun
A complex of phenomena caused by the generation of strong magnetic fields on the Sun
Ejection of matter from the solar corona
Which of the following missions studies the Sun?
What is the measure of length "astronomical unit"?
Distance from the Sun to Mercury
Distance from the Sun to Venus
Distance from the Sun to the Earth
Distance from the Sun to Jupiter
The last stage of the Sun's life cycle is
Black hole
Neutron star
White dwarf
Red giant
The age of the Sun is approximately
3 billion years
4.5 billion years
7.2 billion years
10 billion years
What type of star according to spectral classification does the Sun belong to?
White dwarf
Yellow dwarf
White giant
Red giant
Red dwarf
In what region of the Milky Way is the Sun located?
Orion Arm
Event Horizon
Perseus Sleeve
Dark Zone
The solar activity cycle is approximately
The Sun is mainly made up of
Oxygen
Carbon
Hydrogen
With the sun, option 4
The sun rotates on its axis
A) in the direction of planetary motion
B) against the direction of planetary motion +
B) it does not rotate
D) only its individual parts rotate
2. The distance from the Earth to the Sun is called
A) light year
B) parsec
IN) astronomical unit +
D) annual parallax
3. By mass of the Sun
A) equal to the total mass of the planets of the solar system
B) more than the total mass of the planets +
C) less than the total mass of the planets D) this question is incorrect, since the mass of the Sun is constantly changing
4. The temperature on the surface of the Sun is approximately equal to
A) 3000 0 C B) 3000 0 K C) 6000 0 C D) 6000 0 TO
5. What is the source of the sun's energy?
A) Thermonuclear reactions of fusion of light nuclei
B) Nuclear reactions of chemical elements
IN). Chemical reactions
6. What class of stars does the Sun belong to?
A) supergiant. B) yellow dwarf. B) white dwarf. D) red giant.
7. The most common element in the Sun is
A) helium B) hydrogen C) helium and hydrogen are approximately equal
D) this question makes no sense, since the Sun is plasma
8. What observations confirmed the occurrence of thermonuclear reactions of fusion of helium from hydrogen in the solar core?
A) Observation of the solar wind
B) Observation of sunspots
B) Observation of X-ray radiation from the Sun
D) Observation of the solar neutrino flux.
9. Distribute the solar layers, starting from the outer
A) photosphere B) corona C) chromosphere D) core E) prominences
10. The visible surface of the Sun is called
A) chromosphere B) photosphere B) crown
11. What are the permanent formations in the photosphere called?
A) spicules B) granules c) prominences
12. Where do prominences form?
A) in the chromosphere B) in the photosphere B) in the solar corona D) in the nucleus
13. Granulation on the Sun Explained
A) thermal conductivity B) convection B) energy transfer by radiation
14. How is energy transferred from the interior of the Sun to the outside?
A) Thermal conductivity B) Heat transfer B) convection D) radiation
15. Does not apply to solar radiation
A) thermal radiation B) solar radiation C) radio waves
D) magnetic radiation D) electromagnetic radiation
16. Does the Sun have a magnetic field?
A) yes B) no C) there is no clear answer
17. What phenomena on Earth are associated with solar activity?
A) magnetic storms, earthquakes, increase in man-made disasters
B) auroras, hurricanes, tornadoes, earthquakes
C) polar lights, magnetic storms, increased ionization of the upper atmosphere
18. During what processes do corpuscular flows and cosmic rays occur on the Sun?
A) with solar wind B) with convection movement B) during chromospheric flares
Line UMK B. A. Vorontsov-Velyaminov. Astronomy (10-11)
Astronomy
Natural science
How old is the Sun? Can the Sun cool down?
"What will happen if the Sun goes out?" – the question can be asked either in a scared voice or in a curious one. "How old is the Sun?" – is also one of the popular questions for children and adults.In our new column “Why” we will regularly answer the most interesting ones!
Solar Passport
The Sun, the central body of the Solar System, is a typical representative of stars, the most common bodies in the Universe. The mass of the Sun is 2 * 10 to the 30th power kg. Like many other stars, the Sun is a huge ball that consists of hydrogen-helium plasma and is in equilibrium (more on that below).
How old is the Sun?
It is 4.6 billion years old. Quite a lot, right? Considering that life (arthropods - the ancestors of modern insects) appeared on our planet about 570 million years ago. The simplest organisms much earlier -about 3.5 billion years ago
Can the Sun go out?
There is no need to be afraid that the Sun will go out, because first it will flare up very, very strongly!Inside the star (and any star that is in a state of equilibrium between pressure from inside and pressure from outside), at a certain moment a new stage of thermonuclear fusion flares up. Temperatures become so high - pressure increases so much that the outer shells of the star swell. The star will change irreversibly, turning into a red giant of enormous size. Our Sun will turn into the same giant.
Is the Sun Big?
The diameter of the Sun is almost 1,400,000 km. A lot of? Compare with the picture below! Millions of planets the size of Earth can fit inside the Sun. 99.8% of the mass of the Solar System is concentrated in the Sun. And from 0.2% of everything else the planets are made (with 70% of the planetary mass coming from Jupiter). By the way, the Sun is constantly losing weight: it loses 4 million tons of its mass every second - they fly away in the form of radiation, every moment about 700 million tons of hydrogen turn into 696 tons of helium.
When and how will our Sun explode?
It would be more correct to say that it will turn into a red giant. At the moment, the Sun is in a yellow dwarf state and is simply burning hydrogen. Throughout its entire existence - 5.7 billion years, as we have already said - the Sun has been in a stable mode of hydrogen burning. And this fuel will last him for 5 billion years (more than the Earth has existed since the beginning of time!)
After the next stages of synthesis are turned on, the Sun will turn red, increase in size - up to the Earth's orbit (!) - and absorb our planet. And, yes, before that he will gobble up Venus and Mercury. But life on Earth will cease even before the Sun begins its transformation, because increasing luminosity and rising temperatures will lead to the fact that our oceans will evaporate a billion years before that.
How hot is the Sun?The temperature on the surface of the Sun is approximately 6 thousand degrees Celsius. Inside the Sun, where thermonuclear reactions occur without stopping, the temperature is MUCH higher - it reaches 20 million degrees Celsius.
Is this what happens to all the stars? How then does life appear?
The sun is still a very small star, and therefore can work for a long time, steadily burning its hydrogen. Large stars, due to their enormous mass and the need to constantly resist gravitational compression (what is outside), use their powerful backpressure very quickly to spend their fuel. As a result, their cycle is completed not in billions, like the Sun, but in millions of years. Because of this, life on nearby planets does not have time to arise.Advice to future astronauts: if you are looking for life on planets in other systems, do not choose massive stars, but rather immediately focus on a star of the solar class (Class G - surface temperature 5000–6000 degrees. Color yellow).
The textbook by B. A. Vorontsov-Velyaminov, E. K. Strout meets the requirements of the Federal State Educational Standard and is intended for studying astronomy at a basic level. It preserves the classical structure of presentation of educational material, and pays much attention to the current state of science. Over the past decades, astronomy has made enormous strides. Today it is one of the fastest growing areas of natural science. New established data on the study of celestial bodies from spacecraft and modern large ground-based and space telescopes have found their place in the textbook.
The sun is the only star of our solar system, as well as the center and basis of the entire universe. It's no secret that without heat and light, life on Earth would be impossible. That is why, since ancient times, people have been trying to find an answer to the question, how much longer will the Sun shine and will it stop shining altogether? Today we will tell you about the properties of our star and try to figure out how much time it has left.
The sun in numbers 
Diameter: 1,390,000km
Volume: 1.4 x 10 27 m 3
Temperature: 5500°C
Weight: 1.989 x 10 27 tons or almost 2 trillion quadrillion tons (two followed by 27 zeros)
Volume and mass of the Sun
The Sun is the largest object in our solar system. Moreover, it is so large that its mass 333,000 times the mass of Earth, 1048 times the mass of Jupiter, and 3498 times the mass of Saturn. Moreover, if we add up the mass of all objects in our solar system, the Sun's share will be 99.8%.
The volume of the Sun is 1.4 x 10 27 m 3 . This means that it is about 1.3 million times larger than Earth. Despite this, compared to other stars, the Sun is by no means impressive in size. For example, Betelgeuse, one of the largest stars known to astronomers, is 700 times larger than the Sun and almost 14,000 times brighter.
Temperature on the surface of the Sun
The temperature on the surface of the Sun is 5500-6000°C. Despite this, there are also dark areas on the Sun (Sunspots), whose temperature is approximately 3500°C. According to scientists, the energy and heat of the Sun are generated due to a thermonuclear reaction in its core, and the temperature there is approximately 15,000,000 °C.
Chemical composition of the Sun and the source of its energy
The chemical composition of the Sun is mainly made up of hydrogen.(≈73% by weight) and helium(≈25%). This ratio is constantly changing, as every second the Sun converts 600 million tons of hydrogen into 596 million tons of helium. The remaining 4 million tons of matter are converted into radiant energy, resulting in the generation of solar radiation. Note that all this happens in 1 second and during this time the Sun releases 1 million times more energy than all of humanity consumes in a year.
Age of the Sun
It is believed that The sun formed approximately 4.59 billion years ago and during this time it burned about half of its hydrogen reserves. The average lifespan of this type of star is approximately 10 billion years. Thus, the Sun is now approximately in the middle of its life cycle and will shine for at least another 5 billion years. On the other hand, this glow will be significantly different from today's. As the Sun gradually uses up its hydrogen fuel reserves, it will become hotter and its luminosity will slowly but steadily increase.
In about 1.1 billion years from now on, our daylight will be 11% brighter than it is now. This will lead to significant climate changes on Earth and the extinction of most living beings. Despite this, life may remain in the oceans and polar regions. Interestingly, at this moment, Mars will become the most favorable planet for life.
In another 3.5 billion years, when the star turns 8 billion years old, its brightness will increase by 40%. By that time, conditions on Earth will be similar to conditions on Venus today: water from the surface of the planet will completely disappear and evaporate into space. This catastrophe will lead to the final destruction of all forms of life on Earth.
All this time the Sun will increase in size. Approximately h in 7.6-7.8 billion years, by the age of 12.2 billion years, the radius of the star will be approximately 256 times larger than today. Such stars are called red giants. By then, the Sun will have expanded so much that it will engulf the Earth.
After the Sun passes the red giant phase, its outer shell will be torn off, and a planetary nebula will form from it. At the center of this nebula there will remain a white dwarf formed from the core of the Sun, a very hot and dense object, the size of the Earth, which will cool and fade away over many billions of years.
Located at the center of its own solar system. Eight planets revolve around it, one of which is our home, planet Earth. The sun is the star on which our life and existence directly depend, because without it, we would not even be born. And if the Sun disappears (as our scientists still predict, this will happen in the distant future, in several billion years), then humanity, and the entire planet as a whole, will have a very hard time. That is why it is currently the most important star for us. One of the most intriguing and interesting topics related to space is the structure and evolution of the Sun. This is the question we will consider in this article.
How was this star born?
The evolution of the Sun is a very important issue for our lives. It appeared much earlier than the Earth. Scientists suggest that it is now in the middle of its life cycle, that is, this star is already about four or five billion years old, which is very, very old. The origin and evolution of the Sun are closely intertwined, because the birth of a star plays an important role in its development.
In short, the Sun was formed from a large accumulation of gas clouds, dust and various substances. The substances kept accumulating and accumulating, as a result of which the center of this accumulation began to acquire its own mass and gravity. Then it spread throughout the entire nebula. Things have reached the point where the middle of this entire mass, consisting of hydrogen, acquires density and begins to attract gas clouds and dust particles flying around. Then a thermonuclear reaction occurred, thanks to which our Sun was lit. So, gradually growing, this substance transformed into what we now call a star.
At the moment, it is one of the main sources of life on Earth. If only its temperature had increased by a few percent, we would no longer exist. It was thanks to the Sun that our planet was born and had ideal conditions for further development.
Characteristics and composition of the Sun
The structure and evolution of the Sun are interconnected. It is by its structure and several other factors that scientists determine what will happen to it in the future and how this can affect humanity, the animal and plant world of our planet. Let's find out a little about this star.
Previously, it was believed that the Sun was an ordinary yellow dwarf, representing nothing. But later it turned out that it contains many chemical elements, and very massive ones. If we went into detail about what our star is made of, we could spend an entire article on it, so we can only mention it briefly.
The most significant part in the composition of the Sun is hydrogen and helium. It also contains many other substances, for example, iron with oxygen, nickel and nitrogen, and many others, but they account for only 2% of the composition.
The surface covering of this star is called the corona. It is very thin, so that it is practically invisible (except when the Sun gets dark). The crown has an uneven surface. Due to this, it becomes covered with holes. It is through these holes that the solar wind leaks at tremendous speed. Under the thin shell is the chromosphere, which stretches 16 thousand kilometers in thickness. It is in this part of the star that various chemical and physical reactions occur. This is where the famous solar wind is formed - an influx of a vortex of energy, which is often the cause of various processes on Earth (northern lights and magnetic storms). And the most powerful fire storms occur in the photosphere - a dense and non-transparent layer. The main task of gases in this part is to consume energy and light from the lower layers. The temperature here reaches six thousand degrees. The place where gas energy is exchanged is in the convective zone. From here, the gases rise into the photosphere and then return back to obtain the necessary energy. And in the cauldron (the lowest layer of the star) very important and complex processes associated with proton thermonuclear reactions occur. It is from here that the entire Sun receives its energy.
Sequence of solar evolution
Here we come to the most important question of our article. The evolution of the sun is the changes that occur with a star during its life: from birth to death. It was previously discussed why it is important for people to know about this process. Now we will analyze several stages of the evolution of the Sun in order.
In one billion years
The sun's temperature is predicted to rise by ten percent. In this regard, all life on our planet will die out. So we can only hope that people will have mastered other galaxies by this time. It is also possible that some life in the ocean may still have a chance to exist. There will come a period of maximum temperature of the star in its entire life.
In three and a half billion years
The brightness of the Sun will almost double. In this regard, complete evaporation and volatilization of water into space will occur, after which any earthly life will not have a chance to exist. The earth will become like Venus. Further, in the process of the evolution of the Sun, its energy source will gradually begin to burn out, the cover will expand, and the core, on the contrary, will begin to shrink.
In six and a half billion years
At the central point of the sun, where the energy source is located, the hydrogen reserves will be completely depleted, and helium will begin its own compression due to the fact that it cannot exist in such conditions. Hydrogen particles continue to burn only in the corona of the Sun. The star itself will begin to turn into a supergiant, increasing in volume and size. The brightness will gradually increase with the temperature, resulting in even greater expansion.
In eight billion years (the extreme stage of the Sun's development)
Hydrogen combustion will start throughout the star. This is when its core becomes very, very hot. The Sun will completely leave its orbit in the process of expansion from all of the above processes and will have the right to be called a red giant. At this moment, the radius of the star will expand by more than 200 times, and its surface will cool. The Earth will not be swallowed up by the blazing Sun and will move away from its orbit. It may later be absorbed. But even if this does not happen, then all the water on the planet will still turn into a gaseous state and evaporate, and the atmosphere will still be absorbed by the strongest solar wind.
Bottom line
As mentioned earlier, the evolution of the Sun will greatly affect our lives and the existence of the planet as a whole. As it is not very difficult to guess, in any case it will be very bad for the Earth. Indeed, as a result of its evolution, the star will destroy the entire civilization, perhaps even consuming our planet.
It was easy to draw such conclusions, because people already knew that the Sun is a star. The evolution of the Sun and stars of the same size and type proceeds in a similar way. It was on this basis that these theories were built and confirmed by facts. Death is an integral part of the life of any star. And if humanity wants to survive, then in the future we will have to invest every effort in leaving our planet and avoiding its fate.
Astronomer Petrus Martens from the University of Georgia (USA) said that in ancient times the Sun was heavier than it is today. This allowed the young star to shine as brightly as it does today and provide habitable conditions on Earth and Mars. By now the light had become lighter. The study, available on the arXiv.org electronic preprint library, resolves the faint young Sun paradox. It tells about the life history of the luminary.
The young Sun emerged approximately 4.5 billion years ago as a main sequence object. According to the standard theory of stellar evolution, the Sun was about 30 percent dimmer in ancient times than it is today. It remains a mystery how, with such a faint star, the young Earth was warm enough to provide its surface with liquid water. This contradiction is called the weak young Sun paradox.
The paradox is also relevant for Mars, where seas and oceans of liquid water existed for hundreds of millions of years, although the Red Planet receives about half as much sunlight as Earth.
Geological evidence indicates that water appeared early on Earth and Mars. The past of the Sun can be learned by observing other main sequence stars. Simulations indicate that stars of spectral classes G, which include the closest luminary to Earth, as well as objects of classes K and M, are not developing too quickly, and the habitable zone around such stars is gradually shifting outward.
The weak young Sun paradox has been proposed to be resolved in several ways. The reason for the heating of the planet's atmosphere was called a strong greenhouse effect from carbon dioxide or methane, geothermal energy from an initially warmer earth's core than today, lower albedo of the Earth in ancient times, life developing in a cold environment under an ice sheet 200 meters thick, even the option was proposed with variable gravitational constant.
Martens believes that most of these explanations are seriously flawed. For example, it is not clear when the greenhouse effect should stop so that what happened on Venus does not happen, whose atmosphere is so hot that life is practically impossible in it. In addition, sufficient traces of excess carbon dioxide have not yet been found in ancient geological samples.
Martens believes that many explanations of the young Sun paradox take into account only processes occurring on Earth, and not on Mars, and do not involve an explanation of this contradiction for other planetary systems. In this regard, the American astronomer decided to recall an old but unpopular hypothesis today, according to which the ancient Sun was more massive than it is now.
A star belonging to the same spectral class emits more energy the heavier it is. This means that if in ancient times the Sun shone 30 percent weaker at its present size, we can calculate how much heavier the star closest to Earth was to shine as much as it does today.
About three billion years ago, according to the scientist's estimates, the star lost approximately 0.0000000000075 of its mass every year (about three percent of the initial mass over three billion years of existence); Currently, this value is two orders of magnitude lower and is insignificant for taking into account changes in the brightness of the star. The scientist came to similar conclusions by noting that over time the Sun and most similar stars slow down their rotation.
According to the author, this is due to the loss of mass by the Sun and similar stars (subject to the law of conservation of angular momentum). For example, the large companion binary star 70 Ophiuchi is about 1.1 times lighter than the Sun, is 0.8 billion years old, and is becoming lighter at a rate of 0.000000000003 solar masses per year. In order for conditions suitable for the existence of liquid water to arise on local planets, this mass loss regime must be maintained for about 2.4 billion years.
The loss of their masses by the Sun and similar luminaries in ancient times should have been accompanied by the emergence of stable and strong solar (stellar) winds. The modern Sun does not produce such emissions of matter. It may seem that the sun had no reason to do this before, so the hypothesis of an ancient massive Sun is unpopular. Martens believes that this is not so: the current rate of mass loss by the Sun is not enough to slow down from the initial four to five days to the current 26 days.
Martens's view does not explain how life should survive on a planet irradiated by strong stellar winds. Meanwhile, explanations of the young Sun paradox based on the greenhouse effect do not lose their relevance, and over time, these theories are supplemented.
For example, not only volcanoes, but also asteroids can take part in filling the Earth’s atmosphere with carbon dioxide and methane. Thus, scientists have a new model of gas emission on Earth, which demonstrated the sufficient strength of the greenhouse effect for the existence of liquid oceans already in the early stages of the planet’s development, in low light conditions. Unlike previous studies, which also suggested a possible explanation for the presence of liquid water on ancient Earth through volcanic degassing (the release of greenhouse gases into the atmosphere during volcanic eruptions), the new work takes into account the active bombardment of the planet by asteroids.
Reaching one hundred kilometers in diameter, these celestial bodies, when falling to Earth, cause the melting of large volumes of rock, creating huge lava lakes. As they cool, they release enough carbon dioxide to warm the atmosphere. The bombing of the planet, according to scientists, also led to the release from its depths of sulfur, necessary for the formation of organic life.