In universal life, not only that of humans, the Universe is governed by certain behaviors that are what explain its great functioning, hence the Laws of the Universe. In this way, our environment is also kept in complete order, since it is always necessary for man to elaborate a few laws or norms that explain the attitudes of what is happening around or what should be done, in the legal case.
On the other hand, in the astronomy The laws created were not a human creation. Such laws are constants that explain the proper functioning or behavior of our Universe. In fact, the laws of the Universe are the basis for the study of everything in space. This includes the movement of stars, planets, meteorites, comets, among others. To learn more about the origin of the cosmos, you can consult this article. link.
In addition to this, there are also Universe phenomena. As for this aspect, until now man has not been able to understand the real nature of it. The reason for this is that they are part of a mystery, but it is possible that these anomalies act based on their own laws, which give movement in space. An example of this is the case of dark energy. It is not yet known precisely what it really is or the reason for its accelerated behavior.
The name of the dark energy, arises precisely because energy cannot be visualized, and it is through the obscurity of this phenomenon that its behavior is understood, resulting in an expansive movement at a universal level. For this reason, it is necessary to explain some universal laws that have been discovered by great scholars. In this sense, you can expand your knowledge through books about the universe, which offer fascinating insights.
Kepler's Laws
As has been mentioned, no human being has imposed them, rather they have discovered that the Universe is governed by some laws in order to act in all its splendor. Thus, through studies, scientists have discovered the laws on which the Universe has been based throughout its operation. Thus, providing information that helps the human being to know everything The cosmos or that serves as a collaboration for further studies. A reference in this field is the astronomer Johannes Kepler.
One of these great scholars and collaborators in science was the famous scientist of astronomy, Johannes Kepler. Kepler studied the stars in universal space in such a way that he created what we now call Kepler's Laws. It is not one, but three laws that deal with what refers to the movement of the planets of the Solar System. These laws were formulated at the beginning of the XNUMXth century. However, today they remain valid and function as a basis for previous studies on the behavior of the Universe.
Kepler based his laws on planetary data in order to understand the movements. These data were also collected by the Danish astronomer Tycho Brahewhose assistant he was. For this reason the data remains in scientific research. The proposals that emerged from these investigations broke with the centuries-old assertion that the planets moved in circular orbits. These are the three laws elaborated by Kepler:
Kepler's first law
In this law, Kepler explained that the orbits in Planets revolve around the sun. However, he adds that instead of being circular, they are orbits that are elliptical and in which the Sun occupies one of the foci of the ellipse. That is, the center of this law is based on explaining that the orbits around the Sun are elliptical.
Later, Tycho Brahe made observations in which Kepler made the decision to determine whether trajectories of the planets could be described with a curve. However, by trial and error, he managed to discover that an ellipse could accurately describe the orbit of a planet about the Sun. Principally, ellipses are defined by the length of the two axes they possess.
Regarding the measure, in comparison with a circle it can be said that it has the same diameter up and down, if it is measured widthwise. But on the other hand, an ellipse has diameters of various lengths, it must always be like this since it does not have a form in which all its sides have the same measure, as it happens with the circle. In fact, the longest axis is called the major axis, and the shortest is called the minor axis.
All this explanation comes to light since it is according to this distance that it is known that the planets move in ellipses, although in reality the orbits are almost circular. In addition to planets, comets are also a good example of objects in our Solar System that can have highly elliptical orbits.
When Kepler managed to determine that the planets move around the Sun in the form of ellipses, it was the moment in which he discovered another interesting fact. Kepler evidenced the fact that the speeds of planets vary, as circle the sun.
Kepler's second law
This law is what gives continuity to the previous discovery. This implies that this is where Kepler explains about the speed of the planets. In addition to this, it is at this specific point that he states that the areas swept by the segment that joins the Sun with the planet are also proportional to the times used to describe them. In this way, the speed of the planets is measured, with the consequence that the closer the planet is to the Sun, the faster it moves.
This second law was discovered by Kepler by trial and error. This exploration was birthed when Kepler noticed that the line connecting the planets and the Suncovers the same area in the same period of time. Following this, Kepler found that when the planets are close to the Sun in their orbit, they move faster than when they are farther away. This work led Kepler to obtain an important discovery about the distances of planets.
Kepler's Third Law
Already in this third law, not only explains the speed. In this aspect it is explained above all about distance. The behavior of the planets, according to their distance. For this reason, in this third law Kepler emphasizes that the squares of the sidereal periods of revolution of the planets that revolve around the Sun are proportional to the cubes of the semi-major axes of their elliptical orbits.
According to this law, it is possible to infer that the planets farthest from the Sun are those that orbit at a lower speed than the closest ones. In this way it follows that the period of revolution, depends on the distance to the Sun. The result of this was obtained through the following mathematical formula: P2 = a3. This formula explains that the planets far from the Sun are the ones that take the longest to go around it, unlike those that are close to the Sun.
Isaac Newton's Laws
From the existing laws at the scientific level, the astronomer, physicist and Isaac Newton mathematician, played a crucial role in his work. What Newton did was to explain the orbital path of the moon and each of the artificial satellites that have been launched into space for scientific research. Newton's understanding of the universe helps us better understand the cosmic phenomena.
One of the laws that explain the behavior of the Universe and of the bodies that are within it, is the well-known law of gravitation or law of gravity. This law was formulated by Isaac Newton in 1684. According to what was studied by Newton, the attraction of gravity between two bodies is directly equal to what is the product of their masses. However, it is inversely proportional to the square of the distance between them.
This law that is called law of universal gravitation, it is a law of classical physics. It could be said that it is also fundamental in science, since it describes the gravitational interaction between different bodies with mass. The one who formulated this law was Isaac Newton and published it through his book called Philosophiae Naturalis Mathematics Principle, from the year 1687. This book is where for the first time a quantitative relation of the force with which two objects with mass are attracted is established.
What this explanation demonstrates is that the relationship is empirically deduced through observation. In this way, Newton concluded that the force with which two bodies with unequal mass attract each other, only depends on the value of their masses and the square of the distance that separates them.
Second law of Newton
Newton also managed to determine the behavior that exists between large distances of separation between bodies. In this sense, it was observed that the force of these masses acts in a very approximate way. This is as if all the mass of each of the bodies were concentrated exclusively in the gravity medulla. He means that it is as if these objects were only a point. This is what makes it possible to considerably reduce the complexity of the interactions between complex bodies.
La Newton's second law, explains the acceleration due to gravity. According to this, the effect of the terrestrial gravitational attraction is explained. This indicates that the acceleration supported by a body is proportional to the force exerted on it, it is obtained that the acceleration suffered by a body due to the force of gravity exerted by another. It means that said acceleration is independent of the mass that the object presents, it exclusively depends on the mass of the body that exerts the force and its distance.
Of course, it conforms to both masses being related by a proportionality constant. Which implies that precisely the mass of said object can be introduced in the law of Universal Gravitation, in its simplest form and only for simplicity. For this reason it is necessary for this study to have had two bodies of different mass.
An example between two masses with different masses is the moon and an artificial satellite. Of course, this applies only as long as the satellite has a mass of a few kilograms. In this case they are at the same distance from the Earth, the acceleration that this produces on both is exactly the same. As this acceleration has the same direction as that of the force, that is, in the direction that joins both bodies.
How does this law work?
What produces the gravity acceleration effect If no external force is exerted on either body, they will move in orbit around each other. This behavior perfectly describes planetary motion, or specifically the system between the Earth and the Moon. To broaden your understanding, we recommend exploring other planetary movements.
This law is also dealt with free falling bodies, approaching one body towards the other, as happens with any object that we release in the air and that falls inevitably towards the ground, in the direction of the center of the Earth. Thanks to this law, the acceleration of gravity can be determined, thus producing any body located at a given distance. An example of this is the deduction that the acceleration due to gravity that we find on the Earth's surface is due to the mass of the Earth.
It means that the acceleration suffered by a falling object is practically the same in space, at the distance where the object is. International Space Station. Which implies that it is 95% of the gravity that we have on the surface, only a difference of 5%. It is important to remember that the fact that astronauts do not feel gravity is not because gravity is zero there. Rather it is because of its state of weightlessness or continuous free fall.
Limitations of Newton's Laws
The truth is that the law of universal gravitation is close enough to describe the behavior of a planet around the Sun. And it even explains the same movement of an artificial satellite that is relatively close to Earth. In the nineteenth century it was possible to observe some small problems that could not be resolved.
These drawbacks were similar to that of the orbits of Uranus, which could be resolved after the discovery of Neptune. Especially, was the orbit of the planet Mercury, which instead of being a closed ellipse, as predicted by Newton's theory. It is a ellipse that in each orbit is rotating, in this way the closest point to the Sun, called perihelion, moves slightly. Exactly 43 seconds of arc per century, in a movement known as precession.
At this point, as in the case of Uranus, the existence of a planet more internal to the Sun was also postulated. This planet was called Vulcan, which also would not have been observed because it was so close to the Sun and was hidden by its shine. But the truth is, this planet does not exist. Anyway its existence was unfeasible. This implies that this problem could not be solved, until the arrival of Einstein's General Relativity.
Apart from this inconvenience, currently the amount of observational deviations There are several existing ones that cannot be explained under the Newtonian theory: One of them is the already mentioned orbit of the planet Mercury, which is not a closed ellipse as predicted by Newton's theory. In such a case it would not be a law, but a failed theory, since it is a quasi-ellipse that rotates secularly. This produces the perihelion advance problem that was first explained only with the formulation of the general theory of relativity.
Doppler effect
It is necessary to know, in addition to the aforementioned laws, what is the Doppler effect, as it involves a variation in the wavelength of light. The effect is named after Austrian physicist Christian Andreas Doppler. He explains the apparent frequency shift of a wave produced by the relative motion of the source relative to its observer. This effect is also explained by electromagnetic radiation and the sound produced by bodies, depending on their motion. To learn more about this phenomenon, you can visit this article.
An example of the Doppler Effect is the sound of a car engine up close. Since being far away, it is heard less loudly than being close. In the same way it happens from the moment that a star or an entire galaxy moves away and it happens because its spectrum is shifted towards the blue, but when it moves away it is shifted towards the red. Even today the galaxies in the crosshairs are redshifted, which means that they move away from the earth.
Examples of the Doppler effect occur every day in which the speed at which the object that emits the waves moves is comparable to the propagation speed of those waves. As an example we have the speed of an ambulance (50 km/h), although it may seem insignificant compared to the speed of sound at sea level (about 1235 km/h).
However, it is about 4% of the Speed of sound, this fraction is large enough to prompt a clear evaluation of the change in the sound of the siren from a higher pitch to a lower pitch, just as the vehicle passes by the observer.
visible spectrum
El visible spectrum of electromagnetic radiation, explains that if the object moves away, its light moves to longer wavelengths. This produces a red shift. Also, if the object gets closer, its light has a shorter wavelength, thus it is blue shifted. The deviation it produces toward red or blue is insignificant even for high velocities, such as the velocities concerned between stars or between galaxies.
On the other hand, as for the visibility to the human eye, it cannot capture the spectrum, it can only measure it indirectly using precision instruments such as spectrometers. If the emitting object were moving at significant fractions of the speed of light, the variation in wavelength could be directly appreciable. The Doppler effect is very useful in astronomy, and is manifested in the so-called red shift or blue shift.
This effect is used by astronomers to measure the rate at which stars and galaxies are moving toward or away from Earth. This is about the radial velocities of the Doppler effect. It's about a physical phenomenon which is mainly used to detect binary stars, to measure the speed of rotation of stars and galaxies. Although it is also used to detect exoplanets close to Earth or satellites launched into space.
The most important thing to note is that the redshift is also used to measure the expansion of space. In this case it is not really a Doppler effect. light in astronomy it depends on the knowledge that the spectra of the stars are not homogeneous. According to studies, well-defined absorption lines of frequencies are exhibited that are in correspondence with the energies required to excite the electrons of various elements from one level to another.
absorption lines
The Doppler effect is recognized as the fact that the known patterns of absorption lines do not always appear to agree with the frequencies that are obtained from the spectrum of a stationary light principle. This occurs because blue light has a higher frequency than red light, the spectral lines of an approaching astronomical light source are blueshifted, and those of a receding one are blueshifted. red shift.
Doppler radar
What explains all of the above is that some types of radar use the Doppler effect. They do this with the intention of measuring the speed of objects that have been detected. A group of radars are fired at a moving target. An example can be mentioned of a car, as in the police's use of radar to detect the speed of vehicles.
According to this, as you get closer or farther away from the radar source you can determine the speed of the object. Each successive wave the radar has must travel farther to reach the car, before being reflected and detected again near the source. Analogically it is assimilated to each wave because it has to move further. The distance between each wave increases and this is what produces an increase in wavelength.
In some cases, this radar beam is used with the car in motion and if it gets closer to the observed vehicle, then each successive wave travels a shorter distance, producing a decrease in the wavelength. In any situation, the calculations of the Doppler effect allow to accurately determine the speed of the vehicle observed by the radar. In addition to this, the proximity mechanism, developed during World War II, is based on Doppler radar.
This in order to detonate explosives at the right time based on their height above the ground, or their distance from the target. According to the Doppler shift, the wave incident on the target is affected. In this way, the wave reflected back to the radar, the change in frequency observed by a moving radar With respect to a target that is also moving, it is a function of its relative speed and is double that which would be recorded directly between the emitter and the receiver.
reverse Doppler effect
Even today and since 1968, scientists have studied the probability that there is a reverse Doppler effect. One of the scientists featured in this research was the Russian-Ukrainian physicist Victor Veselago. The experiment claimed to have detected this effect was carried out by Nigel Seddon and Trevor Bearpark in 2003 in Bristol, UK.
In this regard, scholars from different universities stated that this effect can also be observed at optical frequencies. Among the universities highlighted in this research were the Swinburne University of Technology and the University of Shanghai for Science and Technology. Being possible such discoveries, thanks to the generation of a photonic crystal.
It was on that glass that they projected a laser beam. This was what made the crystal behave like a superprism, in this way the reverse Doppler effect could be observed.
In some cases a law can be confused with a theory, but the truth is that theories are a group of organized ideas that explain a possible phenomenon. These are deduced from observation, experience or logical reasoning. However, it explains possibilities and not facts or explains behaviors.
The laws of the Universe are more than we think, in fact these are some that have impacted the course of the history of science. The first thing to understand is that the laws of the Universe, unlike the legal ones or those imposed by man, are the behaviors by which the behavior of the universal. That is, they are the norms that explain the movements of the universal whole.
