What is a satellite? Types of satellites

The star system of the galaxy The Milky Way in which we live includes the Sun and eight other planets revolving around it. First of all, scientists are interested in studying the planets closest to the Earth. However, the satellites of the planets are also very interesting. What is a satellite? What are their types? What are they so interesting for science?

What is a satellite?

A satellite is a small body that makes rotational movements around the planet under the influence of gravity. At present, we know 44 such celestial bodies.

Satellites are absent only in the first two planets of our star system, Venus and Mercury. The earth has one companion (the Moon). The "Red Planet" (Mars) has two celestial bodies, accompanying it - Deimos and Phobos. The largest planet of our star system - Jupiter - has 16 satellites. Saturn has 17, Uranus has 5, and Neptune has 2.

Types of satellites

All satellites are divided into 2 types - natural and artificial.

Artificial - people created by heavenly bodies, which provide an opportunity to observe and explore the planet, as well as other astronomical objects. They are necessary for mapping, weather forecasting, radio signal transmission. The largest man-made "fellow-traveler" of the Earth is the International Space Station (ISS). Artificial satellites are not only on our planet. Over 10 such celestial bodies revolve around Venus and Mars.

What is a natural satellite? They are created by nature itself. Their origin always aroused the genuine interest of scientists. There are several theories, but we will dwell on official versions.

Near each planet there is a cluster of cosmic dust and gases. The planet attracts celestial bodies that fly close to it. As a result of this interaction, satellites are formed. There is also a theory that separates fragments from cosmic bodies that collide with the planet, which subsequently acquire a spherical shape. According to this assumption, the Earth's natural satellite is a fragment of our planet. This is confirmed by the similarity of terrestrial and lunar chemical compositions.

Orbits of satellites

There are 3 types of orbits.

The polar is inclined to the equatorial plane of the planet at right angles.

The trajectory of the inclined orbit is displaced in relation to the equatorial plane by an angle less than 90 ^° .

Equatorial (also called geostationary) is located in the same name plane, along its trajectory the celestial body moves with the speed of revolution of the planet around its axis.

Also, the orbits of satellites are divided into two basic types - circular and elliptical. In a circular orbit, the celestial body moves in one of the planes of the planet with a constant distance above the surface of the planet. If the satellite moves in an elliptical orbit, this distance varies within the period of one revolution.

Natural satellites of the planets of the solar system: interesting facts

Saturn's moon Titan has its own dense atmosphere. On its surface there are lakes, which include liquid hydrocarbon compounds.

Europe (a satellite of Jupiter) is covered with ice, under which the ocean is presumably located. Also, scientists hypothesized that there are active geothermal sources within this ocean.

Another companion of Jupiter, Io, aroused the special interest of astrophysicists. On it active volcanoes are found out.

Artificial Earth Satellites (AES)

According to the generally accepted definition, the satellite is called an aircraft, which at least once made a turn around the Earth. The first artificial satellites were put into near-earth orbit by the Soviet Union (1957) and the USA (1958). Due to this, the density of the upper layers of the atmosphere was measured, and the propagation of radio signals was investigated. This became a real breakthrough in exploring outer space and the beginning of the Space Age.

Following the USSR and the United States, satellites were launched by France (1965), Australia (1967), Japan (1970), PRC (1970) and Great Britain (1971).

The conduct of space research is based on international scientific and technical cooperation. So, for example, friendly countries of the USSR carried out satellite launches from Soviet cosmodromes. Some satellites made in Canada, France, Italy, since 1962 were launched using US launch vehicles.

What is a satellite? It is a cosmic body rotating orbit around a planet . By origin they are natural and artificial. The special interest of the world community is caused by the natural satellites of the planets, because they still have many mysteries in themselves, and most of them are still waiting for discovery. There are projects on their study of private, state and world significance. Artificial satellites allow us to solve applied and scientific problems both on the scale of a single planet and the whole of outer space.