2023-12-17 23:00:00
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Have you ever wondered why satellites, those technological devices that silently orbit our planet, they don’t fall to the earth? It is an effect that requires careful and detailed scientific planning and that unites the laws of physics and space engineering in perfect harmony.
And, from the first rockets created for experimentation to the interconnected network of satellites that surrounds the planet, the history of space exploration has been a complete odyssey. The starting point dates back to the 1950s, when the Cold War fueled competition between the United States and the Soviet Union for space supremacy. He Sputnik 1, manufactured by this last power, marked a milestone by becoming, on October 4, 1957, the first artificial satellite in history. The achievement was followed by other successes, such as the flight of Yuri Gagarinthe first human being to orbit the Earth in 1961, or the arrival of the Apollo 11 to the Moon in 1969.
Video: Curiosities about planet Earth
GRAVITY, CENTRIFUGAL FORCE AND INERTIA
However, to achieve all these space milestones, a great physical, mathematical and engineering development is necessary behind it. And only with appropriate calculations is it possible to determine which point in the Earth’s orbit is the one that combines perfectly the characteristics necessary to host a satellite. But what are those conditions exactly?
How does string theory explain the phenomenon of gravity?
Well, we must bear in mind that, when launching a satellite into space, it must acquire a speed high enough to overcome the force of gravity that would pull it back to the surface. Now, the key is to provide it with exactly the speed that allows it to reach the chosen point in the orbit, the one where its speed is tangential to the planet and, therefore, a centripetal force is generated in the opposite direction.
This is a force that appears in circular movements and that “pulls the object outward.” Do you recognize the feeling that something is trying to separate you when you hold someone’s hands and start spinning? Well, that’s just the centrifugal force. In the case of satellites, when they reach the point where their speed is horizontal, a circular movement is created in which the sensation of gravity and the famous centrifugal force are balanced: that is precisely where the satellite manages to stay in orbit.
Finally, directly linked to this movement, appears the inertia, that is, the tendency of an object to maintain its current state of motion. In satellites, it is that inertia that makes the satellite is driven moving at a constant speed, as a result of the dynamic balance that the gravitational force and the tangential speed have jointly created.
NASA
Launch of the Aquarius SAC-D Launch satellite
THE SUN: A DETERMINING FACTOR
Now, as you can imagine, there may be certain factors capable of to alter this perfect harmony and, one of them, is the Sol. And, did you know that the solar magnetic field itself can affect the orbit of the satellite in low orbit. This is because, at certain altitudes, the solar wind can influence the satellite’s trajectory.
The Sun contributes extra energy to the atmosphere during the times when it is most active, that is, during times of “solar storm”. Under these circumstances, the lower-density layers of the atmosphere move upward and are replaced by those that were lower, denser. Thus, certain satellites that are orbiting the Earth in low orbits may be affected by this phenomenon: if their height change but its speed does not, the component of the centrifugal force will no longer be adequate to balance gravity and the satellite will fall in a way that is difficult to avoid.
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