This is different from the natural satellites, or moons, that orbit planets, dwarf planets and even asteroids. Artificial satellites are used to study the Earth, other planets, to help us communicate, and even to observe the distant Universe. The first artificial satellite was the Soviet Sputnik 1 mission, launched in Since then, dozens of countries have launched satellites, with more than 3, currently operating spacecraft going around the Earth.
List of orbits Various earth orbits to scale; cyan represents low earth orbit, yellow represents medium earth orbit, the black dashed line represents geosynchronous orbit, the green dash-dot line the orbit of Global Positioning System GPS satellites, and the red dotted line the orbit of the International Space Station ISS.
The first satellite, Sputnik 1was put into orbit around Earth and was therefore in geocentric orbit. By far this is the most common type of orbit with approximately 1,  artificial satellites orbiting the Earth.
Geocentric orbits may be further classified by their altitude, inclination and eccentricity. Low Earth orbit is any orbit below 2, km. Centric classifications[ edit ] Geocentric orbit: An orbit around the planet Earth, such as the Moon or artificial satellites. Currently there are approximately 1,  artificial satellites orbiting the Earth.
An orbit around the Sun. In our Solar Systemall planets, cometsand asteroids are in such orbits, as are many artificial satellites and pieces of space debris. Moons by contrast are not in a heliocentric orbit but rather orbit their parent planet.
An orbit around the planet Marssuch as by moons or artificial satellites. The general structure of a satellite is that it is connected to the earth stations that are present on the ground and connected through terrestrial links.
Also known as an intermediate circular orbit. The period of the orbit equals one sidereal daycoinciding with the rotation period of the Earth. High Earth orbit HEO: Orbital Altitudes of several significant satellites of earth.
Inclination classifications[ edit ] Inclined orbit: An orbit whose inclination in reference to the equatorial plane is not zero degrees. An orbit that passes above or nearly above both poles of the planet on each revolution.
Therefore, it has an inclination of or very close to 90 degrees. Polar sun synchronous orbit: A nearly polar orbit that passes the equator at the same local time on every pass. Useful for image taking satellites because shadows will be nearly the same on every pass.
Eccentricity classifications[ edit ] Circular orbit: An orbit that has an eccentricity of 0 and whose path traces a circle. An orbit that moves a spacecraft from one approximately circular orbit, usually the orbit of a planet, to another, using two engine impulses.
This maneuver was named after Walter Hohmann.
An orbit with an eccentricity greater than 0 and less than 1 whose orbit traces the path of an ellipse. An elliptic orbit where the perigee is at the altitude of a Low Earth orbit LEO and the apogee at the altitude of a geosynchronous orbit.
An elliptic orbit where the perigee is at the altitude of a Low Earth orbit LEO and the apogee at the altitude of a geostationary orbit. A highly elliptic orbit with inclination of Such a satellite spends most of its time over two designated areas of the planet specifically Russia and the United States.
Such a satellite spends most of its time over a single designated area of the planet.satellite, artificial Artificial object placed in orbit around the Earth or other celestial body.
Satellites can perform many tasks, including sending back data or pictures to the Earth. Satellites can perform many tasks, including sending back data or pictures to the Earth.
Artificial satellites are used for many purposes, including communications, navigation, gathering weather information, creating maps and even spying. Artificial satellites are human-built objects orbiting the Earth and other planets in the Solar System.
This is different from the natural satellites, or moons, that orbit planets, dwarf planets. Keyword Search. By entering keyword(s), you may use one or more keywords to define a search using the words: and, or, not as separators.
To narrow a search - Use: and, not. mountain and river - will provide items that contain both mountains and rivers. strategies as they write and use different writing between natural and artificial satellites and use images taken by robotic spacecraft and telescopes to gain an understanding of their Artificial satellites are built and placed in their locations by humans.
2. Have students write a friendly letter to. The terms man-made satellite and artificial moon were very quickly abandoned in favor of the simpler satellite, (natural satellites that orbit a natural satellite of a planet) are currently known as of In most cases, the tidal effects of the planet would make such a system unstable.
Images of planets and major moons (not to scale.