What are satellites for?

Who among us did not shout joyfully, looking into the deep starry sky: - Look, look, the satellite is flying! And this satellite was not at all associated with anything other than space.
But now - a completely different story! Satellites are communications, television, determination of coordinates, security, and the Internet. And many more things people will come up with for space technologists to serve for the benefit of man.
And we will tell you why and what are the most popular ways of using satellite systems today.

Why sometimes only satellite technology can be the only development option?
When installing land lines, wires are used - fiber optic or copper, or when wireless technology - cellular networks or radio internet. All these rather costly work always have significant disadvantages:

limiting the coverage of the territory. Any transmitter or receiver of a signal has a certain area of \u200b\u200bwork, which depends on the power and terrain of the area;
issues of network modernization always relate to technical capabilities and the feasibility of spending financial resources;
it is often impossible to quickly dismantle equipment and deploy a station to a new location.

And in some cases, the most justified in a technical and financial sense to ensure reliable and high-quality communication is the use of satellite systems.

Satellites will always find us

Without satellite technology, we would never be able to find each other on our large planet.
The global coordinate system allows you to accurately determine the location of objects (longitude, latitude, and even height above sea level), as well as the direction and speed of this object.
The well-known American GPS (Global Positioning System) system includes 24 artificial satellites, a wide network of ground stations that have unlimited connectivity to user terminals.
GPS - the system works continuously. Anyone on the planet can use it, you just need to purchase a GPS navigator. Manufacturers offer portable, automotive, aviation, marine models. Search work and rescue operations in no country in the world are complete without gPS assistance.

Not so long ago, Russia deployed its GLONASS navigation system, similar to the American one, and with the same level of positioning accuracy.
Both systems are completely available and free.

Satellites guard us

This is especially true in the automotive industry. The main security system is successfully combined with channels satellite communications, GPS and traditional radar methods.
How do satellite security systems work?
The central unit with security sensors is discreetly installed on the car. In the event of an emergency, the signal from the central unit is transmitted via communication channels to the owner or dispatcher. The GPS system helps to track the route, location, driving mode in real time.

Satellites entertain us

The most relevant and well-known topic is satellite TV. But we are already so used to the plates in our homes that we practically do not notice it. But only three devices: an antenna, a receiver, a converter give us extraordinary pleasure from watching our favorite TV programs.
The difference from a traditional television antenna is that instead of a tower, a satellite protrudes and transmits digital signal... This results in a large selection of channels and image quality.

Satellites connect us with friends

The most common and well-known global satellite communication systems (GSSS): Globalstar, Inmarsat, Iridium, Thuraya. At the very beginning of their creation, it was assumed that these systems organize a mobile and fixed telephony where there are no communication lines. In the further development, new opportunities appeared: access to the Internet, transfer of information in various formats. And GSSS have become multi-service.
If you describe the operation of these systems in a nutshell, it will turn out like this.
The satellite receives the subscriber's signal and transmits it to the nearest station on Earth. The station determines the signal, selects a route and sends it over terrestrial networks or satellite channel to the point of reception.
The difference between global satellite communication systems in the cost of traffic, the size and cost of subscriber terminals, coverage areas, as well as technical features the concept of the system itself.

Satellites help us live comfortably

The Very Small Aperture Terminal - VSAT satellite system is actively developing. This system - as a basis for the constructor: you can add equipment and access the Internet, other equipment - and have already been combined local area networks users in different territories. And you can also collect data, reserve communication channels, manage various production processes, organize remote video and audio conferences.
Such a system is easy to deploy and get started. The quality of communication, ease of content and use have already been appreciated by financial institutions, retail chains, and large industrial enterprises.

A VSAT-based network consists of a central control station (NCC), subscriber terminals and a satellite relay.
With further development, all systems will inevitably become more accessible, cheaper, more convenient and easier to manage and understand the ongoing processes of assimilation of our everyday life with satellite technologies.

Now, dreamily looking at the night sky and seeing a moving star, you will think that they, satellites, greatly facilitate and diversify life. And that is great.

Satellites and planets of the solar system

Natural satellites of planets play a colossal role in the life of these space objects. Moreover, even we humans are able to feel on our own skin the influence of the only natural satellite of our planet - the Moon.

The natural satellites of the planets of the solar system have been of great interest to astronomers for a long time. To this day, scientists are studying them. What are these space objects?

Natural satellites of planets are cosmic bodies of natural origin that revolve around planets. The most interesting for us are natural satellites of the planets of the solar system, since they are in close proximity to us.

IN Solar system only two planets do not have natural satellites... These are Venus and Mercury. Although it is assumed that earlier Mercury had natural satellites, however, this planet lost them in the process of its evolution. As for the rest of the planets of the solar system, each of them has at least one natural satellite. The most famous of them is the Moon, which is our planet's faithful space companion. Mars has, Jupiter -, Saturn -, Uranus -, Neptune -. Among these satellites, we can find both very unremarkable objects, consisting mainly of stone, and very interesting specimens that deserve special attention, and which we will talk about below.

Satellite classification

Scientists divide planetary satellites into two types: artificial and natural satellites. Artificial satellites or, as they are also called, artificial satellites - these are spacecraft, created by people, which allow you to observe the planet around which they revolve, as well as other astronomical objects from space. Usually artificial satellites are used to observe the weather, radio transmission, changes in the relief of the planet's surface, as well as for military purposes.

ISS is the largest artificial Earth satellite

It should be noted that not only Earth has satellites of artificial origin, as many people believe. More than a dozen artificial satellites created by mankind revolve around the two planets closest to us - Venus and Mars. They allow you to observe climatic conditions, changes in the relief, as well as receive other relevant information regarding our space neighbors.

Ganymede is the largest satellite in the solar system

The second category of satellites, natural satellites of planets, is of great interest to us in this article. Natural satellites differ from artificial ones in that they were created not by man, but by nature itself. It is believed that most of the satellites in the solar system are asteroids that have been captured by the gravitational forces of the planets in this system. Subsequently, the asteroids took a spherical shape and as a result began to revolve around the planet that captured them as a permanent companion. There is also a theory that the natural satellites of the planets are fragments of these planets themselves, which, for one reason or another, broke away from the planet itself during its formation. By the way, according to this theory, the natural satellite of the Earth, the Moon, arose. This theory is confirmed by a chemical analysis of the composition of the moon. He showed that the chemical composition of the satellite practically does not differ from the chemical composition of our planet, where the same chemical compounds are present as on the Moon.

Interesting facts about the most interesting satellites

One of the most interesting natural satellites of the planets of the solar system is the natural satellite. Charon, in comparison with Pluto, is so huge that many astronomers call these two space objects nothing more than a double dwarf planet. The planet Pluto is only twice the size of its natural satellite.

Astronomers are keenly interested in the natural satellite. Most of the natural satellites of the planets in the solar system are composed primarily of ice, rock, or both, with the result that they lack an atmosphere. However, Titan has this, and it is quite dense, as well as lakes of liquid hydrocarbons.

Another natural satellite that gives scientists hope for detecting extraterrestrial life forms is Jupiter's moon. It is believed that under the thick layer of ice that covers the satellite, there is an ocean, inside which thermal springs operate - exactly the same as on Earth. Since some deep sea life on Earth exists from these sources, it is believed that similar life forms may exist on Titan.

The planet Jupiter has another interesting natural satellite -. Io is the only satellite on the planet of the solar system on which astrophysicists first discovered active volcanoes. It is for this reason that it is of particular interest to space explorers.

Natural satellite research

Studies of natural satellites of the planets of the solar system have interested the minds of astronomers since ancient times. Since the invention of the first telescope, people have actively studied these celestial objects. A breakthrough in the development of civilization made it possible not only to discover a colossal number of satellites of various planets of the solar system, but also to set foot on the main, closest to us, satellite of the Earth - the Moon. On July 21, 1969, American astronaut Neil Armstrong together with the crew of the Apollo 11 spacecraft first set foot on the lunar surface, which caused jubilation in the hearts of the then mankind and is still considered one of the most important and significant events in space exploration.

In addition to the Moon, scientists are actively engaged in the study of other natural satellites of the planets of the solar system. For this, astronomers use not only methods of visual and radar observation, but also use modern spacecraft, as well as artificial satellites. For example, the spacecraft "" for the first time transmitted to the Earth images of several of Jupiter's largest satellites:,. In particular, thanks to these images, scientists were able to record the presence of volcanoes on the satellite Io, and the ocean on Europa.

Today, the world community of space explorers continues to actively study the natural satellites of the planets of the solar system. In addition to various government programs, there are also private projects aimed at studying these space objects. In particular, the world famous American company "Google" is now developing a tourist lunar rover, on which many who wish could take a walk on the moon.

Why sometimes only satellite technology can be the only development option?
When installing land lines, wires are used - fiber-optic or copper, or with wireless technology - cellular networks or radio internet.

All these rather costly work always have significant disadvantages:

Territory coverage limitation. Any transmitter or receiver of a signal has a certain area of \u200b\u200boperation, which depends on the power and terrain of the area;
issues of network modernization always relate to technical capabilities and the feasibility of spending financial resources;
it is often impossible to quickly dismantle the equipment and deploy the station to a new location.

And in some cases, the most justified in a technical and financial sense to ensure reliable and high-quality communications is the use of satellite systems.

Satellites will always find us

Without satellite technology, we would never be able to find each other on our large planet.
The global coordinate system allows you to accurately determine the location of objects (longitude, latitude, and even height above sea level), as well as the direction and speed of this object.
The well-known American GPS (Global Positioning System) system includes 24 artificial satellites, a wide network of ground stations, which have unlimited connectivity to user terminals.
GPS - the system works continuously. Anyone on the planet can use it, you just need to purchase a GPS navigator. Manufacturers offer portable, automotive, aviation, marine models. Search work and rescue operations in no country in the world are complete without the help of GPS.

Satellites guard us

This is especially true in the automotive industry. The main security system is successfully combined with satellite communication channels, GPS system and traditional radar methods.

How do satellite security systems work?

The central unit with security sensors is discreetly installed on the car. In the event of an emergency, the signal from the central unit is transmitted via communication channels to the owner or dispatcher. The GPS system helps to track the route, location, driving mode in real time.
Satellites entertain us
The most relevant and well-known topic is satellite TV. But we are already so used to the plates in our homes that we practically do not notice it. But only three devices: an antenna, a receiver, a converter give us extraordinary pleasure from watching our favorite TV programs.
Difference from traditional television antenna in fact, instead of a tower, a satellite acts and transmits a digital signal. This results in a large selection of channels and image quality.

Satellites connect us with friends

The most common and well-known global satellite communication systems (GSSS): Globalstar, Inmarsat, Iridium, Thuraya. At the very beginning of their creation, it was assumed that these systems organize mobile and fixed telephony where there are no communication lines. In the further development, new opportunities appeared: access to the Internet, transfer of information in various formats. And GSSS have become multi-service.
If you describe the operation of these systems in a nutshell, it will turn out like this.
The satellite receives the subscriber's signal and transmits it to the nearest station on Earth. The station determines the signal, selects a route and sends it over terrestrial networks or satellite channel to the point of reception.
The difference between global satellite communication systems is in the cost of traffic, the size and cost of subscriber terminals, coverage areas, as well as in the technical features of the concept of the system itself.

Satellites help us live comfortably

Satellite system is actively developing Very Small Aperture Terminal - VSAT... This system is like the basis for the designer: you can add equipment and get access to the Internet, other equipment - and the local networks of users in different territories are already united. And you can also collect data, reserve communication channels, manage various production processes, organize remote video and audio conferences.
Such a system is easy to deploy and get started. The quality of communication, ease of content and use have already been appreciated by financial institutions, retail chains, and large industrial enterprises.

Now, dreamily looking at the night sky and seeing a moving star, you will think that they, satellites, greatly facilitate and diversify life. And that is great.

In a broad sense, a companion is a travel companion or companion, one who accompanies someone on the way. But not only humans have satellites. The planets also have their "fellow travelers". What are they? When did an artificial satellite first appear?

The emergence of satellites

In astronomy, the concept of "satellite" first appeared thanks to the scientist Johannes Kepler. He used it as early as 1611 in his work Narratio de Iovis Satellitibus. In the usual sense, planetary satellites are cosmic bodies that revolve around planets. They revolve in their own orbit under the influence of the gravitational forces of their "senior companion".

Natural satellites are bodies that arose naturally, without human intervention. They can be formed from gas and dust, or from a fragment of a celestial body, captured by the planet's gravity. Falling under the influence of gravitational forces, they transform, for example, shrink and compact, acquire a spherical shape (not always), etc.

It is assumed that most of the modern satellites of the planets are their fragments, broken off as a result of a collision, or former asteroids. As a rule, they are composed of ice and minerals, unlike planets, do not have a metal core, and are dotted with craters and faults.

When a satellite is opened, it is assigned a number. Then the discoverer has the right to name him at his own discretion. Traditionally, their names are associated with mythology. Only in Uranus are they named after literary characters.

Satellites of the planets

Planets can have a wide variety of "companions". The Earth has only one - the Moon, but Jupiter has 69. Venus and Mercury have no satellites. Allegations of their discovery periodically appear, but all of them are soon refuted.

Jupiter's moon Ganymede is believed to be the largest in the solar system. It is composed of silicates and ice and reaches 5,268 kilometers in diameter. A complete revolution around Jupiter takes 7 days and 3 hours.

Mars has two "fellow travelers" with the impressive names Deimos and Phobos, which translates from Greek as "horror" and "fear". They have a shape close to a triaxial ellipsoid (the length of the semiaxes is not the same). Scientists claim that the speed of Phobos is gradually decreasing, and he himself is approaching the planet. One day it will simply fall to Mars or collapse, forming a planetary ring.

Moon

The only natural satellite of the earth is the Moon. This is the closest and most studied celestial body outside the planet Earth. It has a core, lower, middle, upper mantle and bark. There is also an atmosphere on the moon.

The satellite's crust consists of regolith - residual soil of dust and rocky fragments of meteorites. The surface of the moon is covered with mountains, furrows, ridges, and seas (large lowlands covered with solidified lava). Its atmosphere is very rarefied, which is why the sky above it is always black and starry.

The movement of the moon around the earth is complex. It is influenced not only by the gravity of our planet, but also by its flattened shape, as well as the attraction of the Sun, which attracts the Moon more strongly. Its full circulation takes 27.3 days. Its orbit is in the plane of the ecliptic, while for most other satellites it is located in the equatorial zone.

The moon also rotates around its axis. However, this movement is synchronized so that it is always turned to the Earth by the same side. The same phenomenon is observed in Pluto with its satellite Charon.

Artificial satellites

Artificial satellites are machines created by man and sent into near-planetary orbit. Inside them are various instruments needed for research.

As a rule, they are unmanned and controlled from earth space stations. To launch them into space, special manned vehicles are used. Satellites are:

research - for the study of space and celestial bodies;
navigation - to determine the location of Earth objects, to determine the speed and direction of the signal receiver (GPS, "Glonas");
communication satellites - transmit radio signals between distant points on Earth;
meteorological - receives data on the state of the atmosphere for weather forecasting.

The first artificial Earth satellite was launched during the Cold War in 1957. It was sent from the USSR and was called "Sputnik-1". A year later, the US released the Explorer 1. Only a few years later they were followed by Great Britain, Canada, Italy, France, Australia and many other countries.

Modern human life is already unthinkable without artificial earth satellites, because with their help we monitor the weather and make its forecast, satellites provide a person with long-distance communication, with the help of satellites, a person conducts unique various studies in space, which is basically impossible on Earth ... But the history of the life of the companion is not yet 60 years old. The first artificial Earth satellite was launched in the USSR on October 4, 1957, exactly 56 years ago. At the moment, a huge number of different satellites fly around our planet in different orbits, doing different work. So which satellites serve a person?

Satellites that provide communication are probably the most popular type of satellite operation and, so to speak, the most obvious, because at high altitudes the signals received and emitted by the satellite can be received at points on the Earth that are at a considerable distance from each other. With the help of communication satellites, we watch TV programs, talk on the phone, go to the Internet.

Satellites providing navigation on the ground. Surely, many have heard of gPS navigation with the help of which a person can determine the location of certain objects with great accuracy. This is the job that navigator satellites do. Using the GPS navigators built in cell phones, PDA and car computers, anyone can determine their location and plan routes based on road signs, search for houses and streets they need on the map, etc.

The next most popular satellite is the meteorological satellite, which monitors changes in the earth's weather and studies the climate of our planet. It is thanks to meteorological satellites that forecasters make up their own weather forecasts.

Of course, the military could not miss such a gorgeous opportunity to spy on each other from space. As they say, I sit high, I look far away. Spy satellites are able to take high-definition photographs of objects on Earth, listen to communications systems, carry out surveillance, and so on.

The satellites are also irreplaceable helpers for scientists in their scientific research. Research satellites study the Earth's magnetic field, radiation conditions, they are used by geodesists, cartographers and other specialists. A special type of research satellites are biosatellites, on which scientists conduct their experiments, solve various technical problems astronautics, etc.

And of course, in their research, satellites are used by astronomers who can observe distant galaxies and other space objects from space, while the earth's atmosphere does not distort signals received from space. One of the most famous astronomical satellites is the famous Hubble Telescope.