How many artificial earth satellites are there? Who owns the Earth's satellites? GPS

The Earth, like any cosmic body, has its own gravitational field and nearby orbits in which bodies and objects of different sizes can be located. Most often they refer to the Moon and the International Space Station. The first one walks in its own orbit, and the ISS - in a low near-Earth orbit. There are several orbits that differ in their distance from the Earth, their relative location relative to the planet, and the direction of rotation.

Orbits of artificial earth satellites

Today, in the nearest near-Earth space there are many objects that are the results of human activity. Basically, these are artificial satellites used to provide communications, but there is also a lot of space debris. One of the most famous artificial satellites of the Earth is the International Space Station.

Satellites move in three main orbits: equatorial (geostationary), polar and inclined. The first lies entirely in the plane of the equatorial circle, the second is strictly perpendicular to it, and the third is located between them.

Geosynchronous orbit

The name of this trajectory is due to the fact that the body moving along it has a speed equal to the sidereal period of the Earth’s rotation. Geostationary orbit is a special case of geosynchronous orbit, which lies in the same plane as the Earth's equator.

With an inclination not equal to zero and zero eccentricity, the satellite, when observed from the Earth, describes a figure eight in the sky during the day.

The first satellite in geosynchronous orbit is the American Syncom-2, launched into it in 1963. Today, in some cases, satellites are placed in geosynchronous orbit because the launch vehicle cannot place them in geosynchronous orbit.

Geostationary orbit

This trajectory has this name for the reason that, despite the constant movement, the object located on it remains static relative to the earth’s surface. The place where the object is located is called the standing point.

Satellites placed in such an orbit are often used to transmit satellite television, because the static nature allows you to point the antenna at it once and remain connected for a long time.

The altitude of the satellites in geostationary orbit is 35,786 kilometers. Since they are all directly above the equator, only the meridian is named to indicate the position, for example, 180.0˚E Intelsat 18 or 172.0˚E Eutelsat 172A.

The approximate orbital radius is ~42,164 km, the length is about 265,000 km, and the orbital speed is approximately 3.07 km/s.

High elliptical orbit

A high elliptical orbit is a trajectory whose height at perigee is several times less than at apogee. Putting satellites into such orbits has a number of important advantages. For example, one such system may be sufficient to serve the whole of Russia or, accordingly, a group of states with an equal total area. In addition, VEO systems at high latitudes are more capable than geostationary satellites. And putting a satellite into a high elliptical orbit costs approximately 1.8 times less.

Large examples of systems running on VEO:

Space observatories launched by NASA and ESA.
Sirius XM Radio Satellite Radio.
Satellite communications Meridian, -Z and -ZK, Molniya-1T.
GPS satellite correction system.

Low Earth orbit

This is one of the lowest orbits, which, depending on various circumstances, can have an altitude of 160-2000 km and an orbital period of 88-127 minutes, respectively. The only time LEO was overcome by manned spacecraft was the Apollo program with the landing of American astronauts on the moon.

Most of the artificial earth satellites currently in use or ever used operated in low Earth orbit. For the same reason, the bulk of space debris is now located in this zone. The optimal orbital speed for satellites located in LEO is, on average, 7.8 km/s.

Examples of artificial satellites in LEO:

International Space Station (400 km).
Telecommunication satellites of a wide variety of systems and networks.
Reconnaissance vehicles and probe satellites.

The abundance of space debris in orbit is the main modern problem of the entire space industry. Today the situation is such that the likelihood of collisions between various objects in LEO is growing. And this, in turn, leads to destruction and the formation of even more fragments and parts in orbit. Pessimistic forecasts suggest that the launched Domino Principle can completely deprive humanity of the opportunity to explore space.

Low reference orbit

Low reference is usually called the orbit of the device, which provides for a change in inclination, altitude or other significant changes. If the device does not have an engine and does not perform maneuvers, its orbit is called low Earth orbit.

It is interesting that Russian and American ballisticians calculate its height differently, because the former are based on an elliptical model of the Earth, and the latter on a spherical one. Because of this, there is a difference not only in height, but also in the position of perigee and apogee.

The first artificial Earth satellite was launched into space on October 4, 1957. Since that time, more than 4,600 launches have been made, as a result of which about 6,000 satellites appeared on the Earth, with the vast majority of them placed in geostationary (GEO - Geostationary Earth Orbit) and low-stationary (LEO - Low Earth Orbit) near-Earth orbits. Despite such a large number of launched satellites, no more than a thousand of them are actually in operation today. But where are the others?

Space debris first appeared in large quantities on June 29, 1961, 77 minutes after the stage of the American space launch vehicle, weighing about 750 kg, entered orbit. More than 200 of its fragments scattered into orbits at altitudes from 300 to 2200 km. And today, in near-Earth orbits, tons of fragments of various destructions are already being monitored in huge quantities: about 15 thousand in size from 10-15 centimeters and larger, several hundred thousand centimeter-sized particles that are inaccessible for constant monitoring, and millions of millimeter-sized particles. The reasons for the destruction of satellites are very different - self-destruction at the end of their service life, accidents, collisions. It happens that spent stages of launch vehicles, which in theory should immediately fall to the Earth at the calculated location after completing their task, fly around the Earth for years.

This is roughly what space debris looks like in low-Earth orbits. The artist drew these drawings specifically for the European Space Agency (ESA). You can view them in good resolution on the Agency's website. .

The lowest orbits mastered by humans are used by Earth surface imaging, weather observation and communications equipment, manned spacecraft and stations. They fly at altitudes from 300 to 2000 thousand kilometers. It is here that approximately 70% of space debris is located and its concentration at the most “populated” altitudes - from 900 to 1500 kilometers - has reached such a value that even if all new satellite launches are stopped now, then from about 2055 the number of newly formed debris objects will begin to exceed its decline (so-called “self-purification”).

Space debris in LEO orbits. .

But in orbits located in the ranges from 2 to 6 and from 12 to 19 thousand kilometers there are practically no spacecraft, since layers of high radiation (Earth’s radiation belts) are located here. It is theoretically possible to stay in vehicles in these orbits for a long time, but for this they need to be protected with lead plates - and they also need to be delivered there somehow, which is difficult and expensive, and, therefore, commercially unjustified. But the region of altitudes between 6 and 12 thousand kilometers is slowly beginning to be “populated” - however, communication satellites are just starting to be launched there.

View of LEO orbits when viewed above the North Pole. .

View of LEO orbits when viewed above the equator. .

Above 22 thousand km above the Earth there is an “unpopulated” region of outer space up to the orbits of geostationary satellites at an altitude of 32,000 - 40,000 kilometers. At an altitude of 35,800 km, the angular velocity of the satellite is equal to the angular velocity of the Earth's surface below them, so the satellites move over approximately the same area on the surface of our planet. This makes GEO an ideal orbit for communications since there is no need to track the satellite to determine where to point the antenna. Our satellite dishes are pointed at such a spacecraft, and we can watch many different television programs.

Simulation of an explosion in GEO orbit. .

What happens in space after the explosion? A geostationary satellite has a speed of about 11 km/sec. At speeds above this threshold (the third escape velocity), space debris could overcome Earth's gravity and fly away from orbit. But you can’t attach a fuel tank and a personal engine to every piece of space debris, so it remains in orbit, spinning around the Earth and multiplying, multiplying, multiplying.

Simulation of an explosion in GEO orbit. On the second day after the explosion. .

Currently, the number of operating stations in geostationary orbit is approximately 350. All of them will eventually turn into space debris, just as about a thousand old objects accumulated there, the size of which is more than 0.5 meters in cross section, have turned into used ones. There is, of course, even more small debris, but it is more difficult to detect them, although there is an entire international system for tracking these objects.

Earth's gravity and centrifugal forces affect geostationary satellites. .

The advantages of satellites moving in GEO orbits are obvious. But there are also disadvantages, and one of them is the large distance between the satellite and the earth's surface. But sufficient power or a large enough antenna can nevertheless overcome this limitation. A more serious limitation is that there is only one geostationary orbit, which means that there is a limited number of places in which geostationary satellites can be placed - this is due to limiting the number of frequencies available for communication so that there is no interference when receiving and transmitting signals from different satellites. But there are some forces that change orbits over time. For example, since the geostationary orbital plane is not aligned with the Earth's orbital plane (the ecliptic) or the Moon's orbital plane, the gravitational pull of the Sun and Moon gradually increases the orbital inclination of each satellite to move the geostationary satellites out of their equatorial orbit.

Orbits at an altitude of 19-22 thousand kilometers from the Earth's surface. .

Here are the satellites of the Russian and US navigation systems (Glonass and Navstar), and systems of the same kind are gradually being deployed for Europe (Galileo) and China (Compass). New generation navigators allow us to navigate the terrain using spacecraft signals from these systems; they are installed in cars, in taxis - anyone can purchase them.

To reduce the risk of collision, geostationary satellites must be removed from the GEO area at the end of their space mission. .

Giving a satellite a third escape velocity today costs twice as much as any move from one GEO orbit to another, and today about a fifth of spacecraft are equipped with additional engines. To carry out such a lift, you need to spend as much fuel as the satellite needs for 3 months of operation. But it is possible to “throw” satellites not so far - raising satellites 300 km above their working orbit allows them to be transferred to a safe “graveyard”, that is, the orbit would become cluttered, but the lifespan of operational satellites would be extended and they would require replacement less often, and, This means that, albeit partially, the garbage problem can be solved. Today this is the only opportunity to preserve the unique resource of GEO orbits.

However, this maneuver is possible if not only there is enough fuel, but also if unplanned failures and malfunctions do not occur, such as communication failures or power supply faults.

Deviation of a GEO satellite from its original orbit. .

The non-ideal, that is, non-circular shape of the Earth's equator causes GEO satellites to slowly "flow" towards one of two stable equilibrium points along the equator, that is, to drift back and forth relative to these points. In addition, the long-term influence of the Sun, Moon and Earth is such that if a satellite runs out of fuel, the orbital plane on which it will revolve around the Earth will gradually (although this does not happen instantly) deviate from its original one. According to the laws of celestial mechanics, the orbital plane precesses with a period of 52 years and an amplitude of about 15°. This means a threat to other geostationary satellites, since twice a day such old debris will cross their GEO orbit.

Correction of the satellite orbit. .

But it's not just space debris that drifts. A working satellite cannot move strictly along the designed orbit. For the same reasons as debris, a GEO satellite constantly drifts out of its ideal orbit, and it is necessary to compensate for this drift by periodically turning on corrective thrusters to push the satellites in the north-south and east-west directions. If ground services did not do this, then all of them in the east-west direction would also “flow” into two natural “depressions” (105° west and 75° east longitude). Due to such maneuvers, the orbit of GEO satellites is not circular, but slightly elliptical, and the distance from the center of the Earth to the satellite fluctuates throughout the day. These fluctuations are quite significant - 10-20 or more kilometers up and down from the ideal orbit. There can theoretically be several satellites in one such elliptical orbit, but to prevent them from colliding, they must be controlled so that they are always in opposite points of this orbit. In practice, due to inevitable errors when performing satellite maneuvers and the inability to super-accurately determine the relative orbit, the satellites do not move along the same trajectories and are not exactly in the “one opposite the other” phase, and now there are usually no more than six satellites in one such one. "window of admission".

Options for what GEO orbits might look like by 2112. .

What will happen if space debris is not “removed” from GEO orbits is already clear. For LEO altitudes, the worst thing is space debris ground into dust. It can rotate there for thousands of years, and if there is a lot of such dust, it will be impossible to fly through it for these thousands of years. Therefore, it is necessary to remove debris in low orbits now, since getting rid of large objects is a real task, and only a wizard can help get rid of microdust. According to experts, the cost of a unit of such “harvesting” equipment will cost ten times more than the launch of one Proton-type launch vehicle. Even if we start using them now, the amount of comic garbage will increase by 2112, but if everything is left to chance and nothing changes in the space business, the situation may become unmanageable.

To ensure that newly launched satellites into space, including this “cleaner”, do not immediately become new objects of space debris, observation, cataloging of flying objects in orbit and modeling of situations at different altitudes of near-Earth space are already underway, taking into account the passage of the Earth through numerous meteoroids. flows, as well as tracking the most dangerous directions of arrival of natural space objects into near-Earth space. This is a complex job that requires special equipment and knowledge. Still, the accuracy of predictions of such situations cannot be guaranteed to be high. This is due to the fact that the number of space users is constantly growing, new technologies are emerging, for which there are simply not enough statistics for predictions, this is also due to the uncertainty of future explosions and collisions of objects in orbit.

Percentage of objects in GEO orbits. .

As of December 2004, of the 1,124 known objects located in GEO orbits, 31% are active satellites, 37% are objects drifting around the Earth, 13% fluctuate approximately around stable equilibrium points, 153 objects on whose orbits there is no data and 60 unidentified (unidentified) objects.

On February 12 of this year, at an altitude of 800 km above Siberia, a Russian satellite launched into orbit in 1993, controlled but not functioning, and an American satellite launched in 1997, providing communications for Motorola (Iridium system), collided. “We never expected the collision. But it is impossible to track the movement of all objects in orbit, and this incident once again highlights the need for close cooperation between countries on space issues,” the Pentagon said, admitting its error in trajectory calculations and clarifying that this is the first time an intact satellite has collided in orbit.

Meanwhile, let us recall that in April 2005, the Americans launched the Dart spacecraft into space, which was supposed to meet with the spent military satellite Mublcom in order to test the autonomous docking method. Both units, by the way, were undamaged objects. As a result of a computer error, the navigation of the vehicles was carried out with errors, they collided, became damaged objects and, as the Americans explained, both should have burned up upon entering the dense layers of the atmosphere without any particular difficulties. One way or another, both of these situations are unplanned, and there can be no guarantees that this will not happen again.

There are enough problems in space without this. To date, almost 200 explosions of space objects have been recorded, and it is quite possible that some of them are associated with collisions with fragments of space debris. It is not always easy to check and prove this. Over the past 10 years, our astronomers have recorded more than 1000 unpredictable changes in drift speed, again some of them can be explained by collisions with small fragments.

The problem of space waste disposal must be solved. .

In general, whatever one may say, tons of space debris is a real problem. How to solve it on a global scale? Scientists from all over the world are doing something now and inventing something for the future. The main thing is that everyone is clear - this is an expensive, complex task, by the way, commercially profitable, and yet not one whose solution can be postponed until the day after tomorrow. Do not forget that several dozen satellites have radioactive substances on board. And today there are already two known cases of radioactive contamination of the Earth’s surface when such devices fall - in Antarctica and Canada.

Of course, this does not mean that we need to roll our eyes in fear and wait tensely for something terrible to happen to us. Scientists scare us not only because of this. For example, in the article “A Big BOOM awaits us on planet Earth in 2012?” V. Berest explains the essence of two theories that appeared not so long ago and do not have official status, but were nevertheless created by people very competent in their fields - in physics and geology - and asks the question: is the concern of ordinary people about the sad forecast of the Mayan calendar so groundless? , if serious experts believe that in many ways December 2012 can make the problem of clogging the Earth’s space orbits in 2112 insignificant compared to the one that “shines” for us? The only good thing is that these are only theories that do not give any unambiguous answers to this question, but only predict events that can happen with a certain degree of probability - which means that they may not happen. So let’s not worry or give up ahead of time. On the contrary, let’s roll up our sleeves, and we will all, as one, understand how important it is not to litter in our own home, especially if this home is our planet, such a fragile Earth.

Just as seats in a theater provide different perspectives on a performance, different satellite orbits provide perspectives, each with a different purpose. Some appear to hover above a point on the surface, providing a constant view of one side of the Earth, while others circle our planet, passing over many places in a day.

Types of orbits

At what altitude do satellites fly? There are 3 types of near-Earth orbits: high, medium and low. At the highest level, farthest from the surface, as a rule, many weather and some communications satellites are located. Satellites rotating in medium-Earth orbit include navigation and special ones designed to monitor a specific region. Most scientific spacecraft, including NASA's Earth Observing System fleet, are in low orbit.

The speed of their movement depends on the altitude at which satellites fly. As you approach the Earth, gravity becomes stronger and the movement accelerates. For example, NASA's Aqua satellite takes about 99 minutes to orbit our planet at an altitude of about 705 km, while a meteorological device located 35,786 km from the surface takes 23 hours, 56 minutes and 4 seconds. At a distance of 384,403 km from the center of the Earth, the Moon completes one revolution in 28 days.

Aerodynamic paradox

Changing the satellite's altitude also changes its orbital speed. There is a paradox here. If a satellite operator wants to increase its speed, he can't just fire the engines to speed it up. This will increase the orbit (and altitude), resulting in a decrease in speed. Instead, the engines should be fired in the opposite direction of the satellite's motion, an action that would slow down a moving vehicle on Earth. This action will move it lower, allowing for increased speed.

Orbit characteristics

In addition to altitude, a satellite's path is characterized by eccentricity and inclination. The first relates to the shape of the orbit. A satellite with low eccentricity moves along a trajectory close to circular. An eccentric orbit has the shape of an ellipse. The distance from the spacecraft to the Earth depends on its position.

Inclination is the angle of the orbit relative to the equator. A satellite that orbits directly above the equator has zero inclination. If a spacecraft passes over the north and south poles (geographical, not magnetic), its inclination is 90°.

All together - height, eccentricity and inclination - determine the movement of the satellite and how the Earth will look from its point of view.

High near-Earth

When the satellite reaches exactly 42,164 km from the center of the Earth (about 36 thousand km from the surface), it enters a zone where its orbit matches the rotation of our planet. Since the craft is moving at the same speed as the Earth, i.e., its orbital period is 24 hours, it appears to remain stationary over a single longitude, although it may drift from north to south. This special high orbit is called geosynchronous.

The satellite moves in a circular orbit directly above the equator (eccentricity and inclination are zero) and remains stationary relative to the Earth. It is always located above the same point on its surface.

The Molniya orbit (inclination 63.4°) is used for observation at high latitudes. Geostationary satellites are tied to the equator, so they are not suitable for far northern or southern regions. This orbit is quite eccentric: the spacecraft moves in an elongated ellipse with the Earth located close to one edge. Because the satellite is accelerated by gravity, it moves very quickly when it is close to our planet. As it moves away, its speed slows down, so it spends more time at the top of its orbit at the edge farthest from Earth, the distance to which can reach 40 thousand km. The orbital period is 12 hours, but the satellite spends about two-thirds of this time over one hemisphere. Like a semi-synchronous orbit, the satellite follows the same path every 24 hours. It is used for communication in the far north or south.

Low near-Earth

Most scientific satellites, many meteorological satellites, and the space station are in nearly circular low-Earth orbit. Their tilt depends on what they are monitoring. TRMM was launched to monitor rainfall in the tropics, so it has a relatively low inclination (35°), remaining close to the equator.

Many of NASA's observing system satellites have a near-polar, high-inclination orbit. The spacecraft moves around the Earth from pole to pole with a period of 99 minutes. Half of the time it passes over the day side of our planet, and at the pole it turns to the night side.

As the satellite moves, the Earth rotates underneath it. By the time the vehicle moves to the illuminated area, it is over the area adjacent to the zone of its last orbit. In a 24-hour period, the polar satellites cover most of the Earth twice: once during the day and once at night.

Sun-synchronous orbit

Just as geosynchronous satellites must be located above the equator, which allows them to remain above one point, polar orbiting satellites have the ability to remain at the same time. Their orbit is sun-synchronous - when the spacecraft crosses the equator, local solar time is always the same. For example, the Terra satellite always crosses it over Brazil at 10:30 am. The next crossing 99 minutes later over Ecuador or Colombia also occurs at 10:30 local time.

A sun-synchronous orbit is essential for science because it allows sunlight to remain on the Earth's surface, although it will vary depending on the season. This consistency means scientists can compare images of our planet from the same season over several years without worrying about too big jumps in light, which could create the illusion of change. Without a sun-synchronous orbit, it would be difficult to track them over time and collect the information needed to study climate change.

The satellite's path here is very limited. If it is at an altitude of 100 km, the orbit should have an inclination of 96°. Any deviation will be unacceptable. Since atmospheric resistance and the gravitational force of the Sun and Moon change the orbit of the device, it must be adjusted regularly.

Injection into orbit: launch

Launching a satellite requires energy, the amount of which depends on the location of the launch site, the height and inclination of the future trajectory of its movement. Getting to a distant orbit requires more energy. Satellites with a significant inclination (for example, polar ones) are more energy-intensive than those circling the equator. Insertion into a low-inclination orbit is aided by the rotation of the Earth. moves at an angle of 51.6397°. This is necessary to make it easier for space shuttles and Russian rockets to reach it. The height of the ISS is 337-430 km. Polar satellites, on the other hand, do not receive any assistance from the Earth's momentum, so they require more energy to rise the same distance.

Adjustment

Once a satellite is launched, efforts must be made to keep it in a certain orbit. Because the Earth is not a perfect sphere, its gravity is stronger in some places. This irregularity, along with the gravitational pull of the Sun, Moon and Jupiter (the solar system's most massive planet), changes the inclination of the orbit. Throughout their lifetime, the GOES satellites have been adjusted three or four times. NASA's low-orbiting vehicles must adjust their inclination annually.

In addition, near-Earth satellites are affected by the atmosphere. The uppermost layers, although quite rarefied, exert a strong enough resistance to pull them closer to the Earth. The action of gravity leads to the acceleration of satellites. Over time, they burn up, spiraling lower and faster into the atmosphere, or fall to Earth.

Atmospheric drag is stronger when the Sun is active. Just as the air in a balloon expands and rises when heated, the atmosphere rises and expands when the Sun gives it additional energy. Thin layers of the atmosphere rise, and denser layers take their place. Therefore, satellites orbiting the Earth must change their position approximately four times a year to compensate for atmospheric drag. When solar activity is at its maximum, the position of the device has to be adjusted every 2-3 weeks.

Space debris

The third reason forcing a change in orbit is space debris. One of Iridium's communications satellites collided with a non-functioning Russian spacecraft. They crashed, creating a cloud of debris consisting of more than 2,500 pieces. Each element was added to the database, which today includes over 18,000 objects of man-made origin.

NASA carefully monitors everything that may be in the path of satellites, since orbits have already had to be changed several times due to space debris.

Engineers monitor the position of space debris and satellites that could interfere with the movement and carefully plan evasive maneuvers as necessary. The same team plans and executes maneuvers to adjust the satellite's tilt and altitude.

Have you ever wondered how many satellites orbit the Earth?

The first artificial satellite was launched into earth orbit on October 4, 1957. Over the years of space exploration, several thousand flying objects have accumulated in near-Earth space.

16,800 artificial objects fly above our heads, among them 6,000 satellites, the rest are considered space debris - these are upper stages and debris. There are fewer actively functioning devices - about 850.

AMSAT OSCAR-7, launched into orbit on November 15, 1974, is considered the longest-lived satellite. This small device (its weight is 28.8 kilograms) is intended for amateur radio communications. The largest object in orbit is the International Space Station (ISS). Its weight is about 450 tons.

Satellites that provide communications to cellular operators (Beeline, MTS and Megafon) are placed in two types of orbits: low and geostationary.

At a low altitude, 780 kilometers from Earth, there is a used...

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Universe > How many satellites are there in space?

Tracked satellites in Earth orbit

On October 4, 1957, the space age began with the launch of the first satellite, Sputnik 1. He was destined to spend 3 months in orbit and burn up in the atmosphere. Since that moment, many devices have been sent into space: in Earth orbit, around the Moon, around the Sun, other planets, and even beyond the solar system. There are 1071 operational satellites in Earth orbit alone, 50% of which are US developed.

Half are located in low Earth orbit (several hundred km). These include the International Space Station, the Hubble Space Telescope and observation satellites. A certain part is located in medium-Earth orbit (20,000 km) - satellites used for navigation. A small group enters an elliptical orbit. The rest rotate in geostationary orbit (36,000 km).

If we could see them with the naked eye, they would appear static. Their availability on...

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What is an Earth satellite?

An Earth satellite is any object that moves along a curved path around a planet. The Moon is the original, natural satellite of the Earth, and there are many artificial satellites, usually in close orbit to the Earth. The path followed by a satellite is an orbit, which sometimes takes the shape of a circle.

To understand why satellites move the way they do, we have to go back to our friend Newton. Newton proposed that a gravitational force exists between any two objects in the Universe. If not for this force, a satellite moving near the planet would continue to move at the same speed and in the same direction - in a straight line. However, this rectilinear inertial path of the satellite is balanced by a strong gravitational attraction directed towards the center of the planet.

Earth satellite orbits

Satellite orbits

Sometimes the orbit of an Earth satellite looks like an ellipse, a squashed circle that moves around two points known as foci. The same applies...

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British scientists have called ineffective government management the best indicator of the rate of decline in biodiversity among all anthropogenic factors. At the same time, biodiversity is rapidly declining even in officially protected areas, nature reserves and national parks.

Genetic analysis conducted by David Schill and Nathan Hollenbeck has confirmed that a separate species of octopus lives in the very north of the Pacific Ocean, in the area of Alaska and the Bering Sea. They prefer not only cold, but also deeper waters, so they are less likely to be seen by divers.

Let us recall that at the end of November an accident occurred on the Soyuz-2.1b rocket launched from the Vostochny cosmodrome. The reason for the fall of the Fregat upper stage with 19 satellites into the Atlantic Ocean was the incorrect operation of the software algorithms.

The agency's interlocutor said that the Angosat-1 satellite successfully reached its position in geostationary orbit....

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3D printers are the same as Forbes, only better.

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Moscow. December 30th. INTERFAX.RU - Problems that arose after the launch of the Angolan communications satellite Angosat were related to the compatibility of Russian and French standards of equipment on board, an informed source told Interfax.

Angosat successfully reached its stationary position in geostationary orbit. After its launch, problems arose due to “inconsistencies” between Russian and French regulations,” the source said.

He clarified that the satellite has French-made components, and difficulties have arisen with the compatibility of its standards with Russian ones.

“The problem was solved remotely by a group of young employees of RSC Energia, which was developing the spacecraft,” the agency’s interlocutor said.

Angosat was launched into orbit by a Zenit rocket, which launched from the Baikonur Cosmodrome at 22.00 Moscow time on December 26. After eight minutes of normal flight, the Fregat upper stage separated from the rocket, which launched the satellite into the calculated orbit in...

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Most navigation satellite systems appeared in response to requests from the military and were for a long time limited to GPS and GLONASS. However, after it became clear that data from satellites can be effectively used for peaceful purposes, the number of systems began to grow systematically.

We have studied the most significant NSSs existing today.

Active satellites: 31
Total satellites in orbit: 32

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Angosat-1 is the first Angolan telecommunications satellite, which is planned to be operated in geostationary orbit to provide communications and broadcasting in Angola, as well as other countries in Africa and southern Europe. The satellite's mass is 1647 kg. Estimated service life is 15 years.

The rocket was launched with the Angosat-1 satellite. The Zenit-3SLBF launch vehicle is one of the modifications of the Zenit launch vehicle family, developed by Yuzhnoye Design Bureau. Produced at Yuzhmash.

Satellites located in GEO rotate synchronously with the Earth, so they are constantly above a certain area. The position of the devices on the geostationary orbit is called the standing point. As the head of RSC Energia, Vladimir Solntsev, previously reported, Angosat will move to its operating point (over Africa) within two months. Now both objects discovered by NORAD are located above the equator, but much further east - at coordinates 46 and 37 degrees east longitude.

“Two new objects have been detected in orbit, related...

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The first artificial Earth satellite was launched in 1957 in the USSR. Since then, more than 6,000 satellites have been sent into space. Satellites are becoming increasingly important to life on Earth. They are used for a variety of purposes: security, communication, navigation, entertainment, and - most importantly - they allow us to see our planet in a new light. Here you can find out who owns the satellites, where they are located and what their purpose is.

Who has the most companions?

Of the total 957 operational satellites currently in orbit, 423 belong to the United States. Next in terms of the number of satellites is Russia. China also has a significant presence in the orbit. At least 115 countries are co-owners of satellites. This diagram shows the countries where the owners or operators of the satellite are located.

44 countries around the world cooperate in launching and operating satellites (usually a group of two or three countries). Here they are listed as joint projects. USA, Taiwan, Japan and France...

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Geostationary orbit

The orbits in which satellite relays are located are divided into three classes:

Equatorial(1); inclined(2); polar(3).

An important variation of the equatorial orbit is the geostationary orbit, in which the satellite rotates with an angular velocity equal to the angular velocity of the Earth, in a direction coinciding with the direction of rotation of the Earth. The obvious advantage of the geostationary orbit is that the receiver in the service area “sees” the satellite constantly.

The geostationary orbit is determined using a simple mathematical relationship: the angular velocity of the satellite is equal to the angular velocity of the Earth's rotation. Despite its simplicity, this relationship holds for a single trajectory that “hangs” at a distance of slightly less than 36,000 km above the equator. In geostationary orbit, the satellite is stationary for an observer on Earth. This is the main advantage of the geostationary orbit. Therefore, the antennas are also stationary...

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India's communications satellite GSAT-1, launched on April 18 by India's first launch vehicle, failed to enter geostationary orbit due to fuel shortage.

As representatives of the Indian Space Research Organization told RIA Novosti on Wednesday, the satellite is now in orbit with a period of revolution around the Earth of 23 hours instead of the required 24 hours, so its payload cannot be used for its intended purpose.

The problem arose as a result of the fact that the two fuel tanks supplied fuel to the engines in unequal quantities, so the rocket’s flight path changed.

To level it, additional fuel was consumed, and therefore it was not enough to adjust the orbit at the last stage.

The Indians plan to carry out the next launch of a launch vehicle with a geostationary satellite in the second half of 2002...

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GPS - the beginning of global navigation

Active satellites: 31
Total satellites in orbit: 32
Average height from Earth: 22180
Time to complete a revolution around the Earth: 11 hours 58 minutes

The American system appeared in 1974 and immediately created a sensation with its effectiveness. The US government even had to artificially reduce the accuracy of coordinate determination in order to maintain advantages for its military. They got rid of the self-created difficulties only in 2000 - after the decree of Bill Clinton. Initially, the GPS architecture involved the use of 24 satellites, but for greater reliability there are 32 slots in orbit, of which 31 are constantly in use. Each satellite circles the Earth twice a day and is controlled from the Schriever military base by radio signals with a frequency of 2000-4000 MHz. GPS has been and remains the undisputed leader among such systems, and finding a GPS device without a GPS-enabled chip is quite difficult - at least in the Western Hemisphere. Despite...

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Everything you need to know about Geostationary Satellite Orbit

In this material we will look at the basic principles and concepts of geostationary orbit (GEO).

A very popular satellite orbit is the geostationary orbit. It is used to host many types of satellites, including direct broadcast satellites, communications satellites, and relay systems.

The advantage of geostationary orbit is that the satellite located in it is constantly located in the same position, which allows a fixed antenna of a ground station to be pointed at it.
This factor is extremely important for systems such as direct broadcast via satellite, where the use of a constantly moving antenna following the satellite would be extremely impractical.

Care must be taken when using abbreviations for geostationary orbit. We may come across the abbreviations GEO and GSO, and...

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» Cosmodromes and space exploration » How many artificial satellites fly above the earth?

Artificial satellites are designed for broadcasting satellite television, telephone and radio communications, and the Internet. Thanks to these satellites, weather forecasters are able to predict the weather several weeks in advance. In addition, they are used for scientific research. These days there are a huge number of artificial satellites flying around the globe. They vary in shape, weight and appearance.

Today, more than 16 thousand satellites circle the planet. However, many of them have not been working for a long time. In addition, various fragments of broken spacecraft continue to fly around the Earth - they are called space debris. More than 170 satellites are in geostationary orbit, which travels at an altitude of over 35 thousand meters above the Earth. It is at this altitude that the satellite orbits our planet at the same speed with which it revolves around the Sun.

Global Positioning System satellite. Thanks to it, navigation systems work in millions of buses and cars, on airplanes and other types of transport.

Satellite number 1

In October 1957, the world's first artificial satellite, Sputnik 1, was launched into Earth orbit by the Soviet Union. It was a ball that weighed just over 80 kilograms and was equipped with 4 antennas for transmitting signals. Sputnik 1 went into space on a launch vehicle; a few minutes after takeoff, it separated from the rocket and transmitted its call signs to Earth. Sputnik 1 spent 92 days in space, completing 1,440 revolutions around the Earth.