Information about our immediate space environment is becoming publicly available: ordinary users can, without leaving their homes, calculate the distances to neighboring planets and the travel time to them. Interested in the question of the distance of Mars from the Sun, it is worth familiarizing yourself with the basics of measuring cosmic distances.
How is the distance to the stars measured and what is a light year
Units of distances in space are special, derived from the international system of measurement in a separate column.
A.e. is a measure of distance in astronomy, showing the distance of the average location of the third planet - the Earth - from the Sun.
A.e.- a unit of measurement of distances in astronomy, equal to 149,597,870 km
You can also call this unit the radius of the orbit of our planet.
AE is the distance between the centers of the earth and its orbit In astronomical units, you can measure the distances between objects within the same star system similar to solar. For the scales of the Universe a.u. is a very small unit. Therefore, the distance between stars and galaxies is expressed in light years.
In physics, light has long been the standard of the fastest phenomenon in the world, but on a cosmic, non-embracable scale, even light does not move instantly. On the way from one corner of the Universe to another, light slows down, scatters, changes its spectrum, and encounters material obstacles.
Light year- this is the stellar distance that light has time to overcome in one Earth year 9,460,730,472,580,800 km
The distance of one light year is equal to the product of the speed of light and one Earth year. The Julian year must be converted to seconds before multiplication, since the speed of light is also expressed in seconds.
Julian year(a) - a unit of time in astronomy equal to 365.25 Julian days
Relying on astronomical units can perform more complex calculations.
light speed
What is meant by rays of visible light is a stream of non-atomic particles of photons, whose name comes from the Greek term "photos" - "light".
For an earthling, one light year is an insurmountable distance. The average person on their own in the conditions of the Earth's gravity can reach a speed of about 20 km / h. Photons travel 60 million times faster and travel 300,000 kilometers every second. This is the maximum speed achievable by visible light in a vacuum.
speed of light in vacuum is 299 792 458 m/s
In the resistance of the air or water environment, for example, in the atmosphere or oceans of the Earth, respectively, light loses no more than 25% in speed and overcomes 225 thousand km per second.
All other calculations follow from these data, making it possible to assess the possibility of flights around the solar system and between stars. In one minute, light travels 18 million kilometers of outer space.
The closer a person approaches technological progress reaching the speed of light, the less time will need to be spent on space travel.
How many light years to Mars
How to overcome a huge distance and we have long known on practical examples.
How long it takes for Earth astronauts to fly to the red planet is an equation with a variable value, because our planet and Mars are constantly in motion. Each planet is in its own orbit around the sun. The planets can approach each other or be on opposite sides of the star at the maximum distance.
Of course, the most economical solution for earthlings would be to take a flight to Mars when the planets are at their minimum distance.
The distance that light travels in one year is 9460.73 billion kilometers. The minimum possible distance between Earth and Mars is 54.55 million km.
0.0000057 light years from Earth to Mars Having such data, we can conclude that the minimum distance between two planets is 181 light seconds, or 3 light minutes. In other words, there are 0.00000570776255707763 light years between Mars and Earth.
How much light flies to Mars
Despite the physical inaccessibility, it is possible to accurately calculate how long, on average, it takes starlight from the Sun to Mars.
The flight to Mars from the central star of the solar system can be accomplished by a photon - a light particle - without taking into account obstacles and interference in 12.01 minutes. The calculations come from constant speed light in a vacuum - 300 thousand kilometers per second - and the average distance of the red planet from the star, equal to 228 million km.
228,000 thousand km / 300 thousand km / s = 760 s = 12 minutes 1 second - the time required to fly from the Sun to Mars or back at the speed of light. The distance when Mars is at aphelion, the light will travel in 13.01 minutes, at perihelion in 11 minutes.
How much time to fly to Mars at the speed of light
The time of a hypothetical flight to Mars is easy to calculate based on the above knowledge. There is a precisely calculated flight path, capabilities and a minimum distance from Earth to Mars. It is over 54 million km, which is 3 minutes for a light flux. Only if you move at the speed of light, you will have to fly to Mars not for countless months, but almost instants. Three minutes between Mars and Earth at the speed of light is difficult to compare with any terrestrial transport.
The red planet will be within reach if humanity advances to fly at light speed. With the current pace of scientific development, the discovery of new futuristic modes of transport is only a matter of time.
This fiery sphere is too bright for the naked eye. But if you look deeper into it, you can see the true nature of the Sun. This giant ball of hot gas is the largest object solar system. The sun produces heat and light. It is the source of energy for life on Earth. Deep in the bowels of the sun is constantly happening nuclear reaction. Our star is dangerous, but we cannot live without it. No aspect of life would continue without the Sun.
Light is one of the fundamental components of our universe, a fundamental part of everything that exists. This phenomenon is not only the most important, but also the fastest in space. The speed of light reaches 300,000 km/s. Since the distance to the Sun is about 150 million km, then light reaches the earth in about 8 minutes. But these 8 minutes are just the final throw in his journey. It will take about a million years before the light leaves the inner harsh environment of the Sun. And this means that the light that people see on Earth now was produced long before human civilization appeared.
The sun has several layers of heavy gas hundreds of thousands of kilometers thick. And in its center is the nucleus that gives birth to sunlight. And one of the most destructive reactions in the universe gives birth to him - nuclear fusion (conversion of hydrogen into helium). If you connect two hydrogen atoms, a reaction will occur and you get helium. Sounds simple, but it's not. In fact, it is not easy to connect two atoms, because two protons have the same positive charge and therefore repel each other. Protons don't like to get close to each other. It takes a lot of energy to merge them, and this happens very rarely. The bonding of protons uses the enormous amounts of heat and pressure that gravity produces.
The sun contains about 99.8% of the matter in the entire solar system., and all this mass holds the layers of the Sun together with the help of the most powerful gravitational force. Gravity helps hydrogen atoms combine and this is how nuclear fusion occurs. In this nuclear reactor, hydrogen atoms combine an "infinite" number of times per second. Some collisions are so violent that the atoms fuse, releasing energy. But surprisingly, she is incredibly weak. During fusion, less than 1% of protons are converted into energy, which is not enough even for a car engine. And only synthesis gives birth to this energy. Most protons colliding are not synthesized. This allows the Sun to live another 10 billion years.
Path smallest particle of light - photon, begins in the hot core of the Sun. A photon, born in the form of a gamma ray, flies out of the solar core at the speed of light. If there were no obstacles for him, at such a speed he would break through the surface of the Sun in 2 seconds. The sun is so dense that it takes a beam of 100,000 if not millions of years to break through its layers of various gases to the outside. After leaving the solar core, the newborn photon makes its way through a thick layer of hydrogen atoms. The thickness of this layer is more than 600 thousand km. It will take a photon 100 years to overcome it. After that, a breakthrough begins through the solar plasma, which stretches for 320 thousand km. It has an electrical charge that prevents the photons from moving. Its particles hold a photon for a fraction of a second, then release it and it collides with other plasma particles. All these processes last for thousands and even millions of years, until, finally, the photon breaks out and continues on its way to the Earth or other corners of the universe.
Many people think that the central star of our galaxy just shines, and its rays propagate instantly, but this is not so. How to calculate how long it takes the light from the Sun to the Earth, why this value will differ at different times of the year - facts that will be of interest not only to children, but also to adults.
How does the sun shine
Sunlight, which warms all life on Earth with its rays, is the result of complex chemical reactions. The sun is a big hot ball. It has several layers of hydrogen and helium hundreds of thousands of kilometers thick. The temperature on the surface of a star is 6000 Kelvin or 5726.85°C. At the core, where sunlight is born, this figure is much higher - 15 million °K.
At this temperature and pressure, the reaction proceeds continuously thermonuclear fusion inside the nucleus: 4 hydrogen atoms fuse to form a helium nucleus. This is repeated an infinite number of times. In one second, as a result of such fusion, 600 million tons of hydrogen become helium. And every 70 thousand years, the sun converts hydrogen in an amount equal to the mass of the Earth.
As a result of thermonuclear fusion, a large number of energy in the form of photons - massless particles that exist only by moving at the speed of light. During its lifetime, a photon is emitted and absorbed millions of times by gas molecules.
An interesting fact: it takes a photon 200,000 years to get from the core of the Sun to the surface.
How long does light travel from the sun to the earth
To calculate the time it takes a ray of light to reach the Earth, you need to know the distance between our planet and the luminary, as well as the speed of light. The first attempts to calculate the path that an infinite number of photons travel every day were made at the end of the 17th century. Scientists of that time received a figure - 139 million km, but it was inaccurate.
Later, more accurate calculations were made, according to which the distance from the Sun to the Earth is 150 million km. Although this value is taken as a constant and is called an astronomical unit, our planet moves in an elongated elliptical orbit, so the distance between two celestial bodies changes. In January, it is reduced to 147 million km (perihelion), and in July the maximum mileage is 152 million km (aphelion).
In 1975, the exact speed of photons in vacuum was established as 299,792,458 m/s, but most calculations use its approximate value of 300,000 km/s.
The time required for the solar rays to overcome the distance to the Earth in different segments of the orbit of our planet is given in the following table:
Thus, at any time of the year, sunlight reaches the Earth in 8 minutes and 3-25 seconds. If suddenly the Sun went out, then earthlings would know it after the specified time.
Interesting: solar radiation is able to penetrate deep into the ocean at 85 meters, and passing through various substances, it can slow down or refract, focusing at one point.
How long does it take for light to reach Earth from other objects?
To determine the distance between various objects in space, astronomy uses such a quantity as a light year. This indicator is equal to the path that light travels in outer space in a standard Earth year. In quantitative terms, a light year is 9,460,730,472,580,800 meters, or more than 63,000 astronomical units.
The time it takes photons of sunlight to travel to the following objects in the universe will be:
- for the farthest planet from the Sun, Pluto, photons - 5 hours;
- for the farthest point of our system, a cloud of asteroids and Oort fragments, as much as 1.5 years;
- for the brightest star closest to Earth, Proxima Centauri, 4 years.
Light travels the distance between the Moon and Earth in 1.2 seconds, and radio waves travel at the same speed. This creates difficulties in controlling spacecraft (for example, Lunokhod), since the signal arrives and leaves with a delay.
Light does not travel instantly. This is the reason why many cosmic phenomena can be observed with a long delay. Yes, bright polar Star located at a distance of 400 light years from Earth. Its rays, which can be observed now, were sent back in the time of Columbus.
We take the Sun for granted, but how does it shine? What is going on inside it? As you probably know, the Sun is a huge ball of hydrogen and helium.
At the surface, the temperature is about 6,000 Kelvin, but as you dive towards the core, the temperature and pressure increase. By the time you reach the core, the temperature will be around 15 million Kelvin.
At such temperatures and pressures, the fusion reaction begins.
Inside the nucleus, four hydrogen atoms combine to form a helium nucleus. This process happens an infinite number of times, every second.
More than 600 million tons of hydrogen are converted into helium every second. The sun converts a mass of hydrogen equivalent to the mass of the Earth every 70,000 years. As far as you know, the time from the luminary to the Earth, the beam of light reaches in 8 minutes, but the radiation in the form of solar flares reaches the Earth in much longer time.
The path of light from the core
As a result of the fusion reaction, a huge amount of energy is released in the form of photons. These photons are emitted and absorbed by gas molecules. During the lifetime of a photon, this process occurs millions of times.
Surprisingly, it takes a photon 200,000 years to get out of the center to reach the surface.
Light takes hundreds of thousands of years to travel from the core to the surface. A beam from the Sun to the Earth reaches in just 8 minutes.
quoted1 > > > How long does sunlight get to Earth?
speed of light- how long does sunlight travel from the Sun to the Earth: a description of the Earth's orbit in the photo, the distance and place of the third planet in the solar system.
It seems strange, because everyone thinks that the Sun just shines and everything happens as if instantly. The sun's rays move towards us at the speed of light and move in a vacuum environment. In short, the whole journey takes 8 minutes and 20 seconds. Yes, the irony is that if our star suddenly disappears somewhere, then it will reach us only after 8 minutes.
Understanding the speed of light is important in astronomy, so let's turn to mathematics. The distance from the Earth to the Sun is 150 million km, and the speed of light is 300,000 km/s. We divide and get the specified time. But this is an average.
Let's also remember that our planet rotates in an elliptical orbital path and the distance changes by 147-152 million km. Then, at maximum approach, the speed will be 490 seconds, and at a distance - 507 seconds. But further is even more interesting.
A fusion occurs inside the solar core, which leads to the formation of photons. It all starts in the form of gamma rays, which are absorbed many times by a star, travel inside it, and only then break through to the surface. But the most amazing thing is that the actual light that reaches you was created tens of thousands of years ago! He managed to escape and in 8 minutes finally get to you.
Yes, when you look into space, you literally see traces of the past everywhere. Reflected moonlight moves towards us for a second. But Alpha Centauri takes more than 4 years. Now think about the stars in other galaxies that take millions of years just to see their beautiful glow.
Let's look from the other side. If there are intelligent aliens who are now considering our planet, then they will see only dinosaurs. This is why the speed of light is important to scientists and cosmologists.