In the context of spaceflight
Spaceflight is the act of travelling into or through outer space. Spaceflight can occur with spacecraft which may, or may not, have humans on board. Examples of human spaceflight include the Russian Soyuz program, the U.S. Space shuttle program, as well as the ongoing International Space Station...

, a satellite is an object which has been placed into orbit
In physics, an orbit is the gravitationally curved path of an object around a point in space, for example the orbit of a planet around the center of a star system, such as the Solar System...

 by human endeavour. Such objects are sometimes called artificial satellites to distinguish them from natural satellite
Natural satellite
A natural satellite or moon is a celestial body that orbits a planet or smaller body, which is called its primary. The two terms are used synonymously for non-artificial satellites of planets, of dwarf planets, and of minor planets....

s such as the Moon
The Moon is Earth's only known natural satellite,There are a number of near-Earth asteroids including 3753 Cruithne that are co-orbital with Earth: their orbits bring them close to Earth for periods of time but then alter in the long term . These are quasi-satellites and not true moons. For more...


The world's first artificial satellite, the Sputnik 1
Sputnik 1
Sputnik 1 ) was the first artificial satellite to be put into Earth's orbit. It was launched into an elliptical low Earth orbit by the Soviet Union on 4 October 1957. The unanticipated announcement of Sputnik 1s success precipitated the Sputnik crisis in the United States and ignited the Space...

, was launched by the Soviet Union in 1957. Since then, thousands of satellites have been launched into orbit around the Earth
Earth is the third planet from the Sun, and the densest and fifth-largest of the eight planets in the Solar System. It is also the largest of the Solar System's four terrestrial planets...

; also some satellites, notably space station
Space station
A space station is a spacecraft capable of supporting a crew which is designed to remain in space for an extended period of time, and to which other spacecraft can dock. A space station is distinguished from other spacecraft used for human spaceflight by its lack of major propulsion or landing...

s, have been launched in parts and assembled in orbit.

1957    Project Vanguard: A launchpad explosion of Vanguard TV3 thwarts the first United States attempt to launch a satellite into Earth orbit.

1958    Explorer program: ''Explorer 1'' – The first successful launch of an American satellite into orbit.

1958    The United States launches the Vanguard 1 satellite.

1958    The Soviet satellite Sputnik 2 falls from orbit after a mission duration of 162 days.

1962    First transatlantic satellite television transmission.

1962    ''Alouette 1,'' the first Canadian satellite, is launched.

1962    NASA "Relay 1" launch, first active repeater communications satellite in orbit.

1965    Launch of Early Bird, the first communications satellite to be placed in geosynchronous orbit.

1965    In the Hammaguir launch facility in the Sahara Desert, France launches a Diamant-A rocket with its first satellite, ''Asterix-1'' on board, becoming the third country to enter outer space.

1970    The first Chinese satellite, Dong Fang Hong I, is launched.