PlayInfoBox

Home /Education /Types and Roles of Artificial Satellites

Types and Roles of Artificial Satellites

Click on an entry to see the details.

1. Communications satellites

Satellites that relay broadcast signals, internet, international phone calls, and more; most are placed in geostationary orbit (GEO), matching Earth's rotation period, so they appear fixed over the same region of the sky at all times.

2. Weather satellites

Satellites that observe cloud movement, typhoon paths, precipitation, and more. South Korea operates the Cheollian 2A in geostationary orbit, providing real-time weather information for the East Asian region.

4. Earth observation satellites

Satellites that photograph the Earth's surface for use in land management, disaster monitoring, and environmental monitoring. South Korea's Multi-Purpose Satellite (Arirang) series is a representative Earth observation satellite.

5. Science satellites

Satellites designed to observe or study space itself, such as the Hubble Space Telescope or the James Webb Space Telescope, which observe celestial objects.

6. Characteristics of low Earth orbit (LEO)

An orbit at an altitude of roughly 2,000 km or below; being close to Earth allows for short communication delays and high-resolution observation. The International Space Station (ISS) and the Starlink satellite constellation use this orbit.

7. Characteristics of geostationary orbit (GEO)

At an altitude of about 35,786 km, satellites here orbit on a 24-hour cycle matching Earth's rotation, so from the ground they appear to always float in the same position. Communications and weather satellites mainly use this orbit.

8. The first artificial satellite, Sputnik 1

Humanity's first artificial satellite, successfully launched by the former Soviet Union on October 4, 1957. This spherical satellite, about 58 cm in diameter, orbited Earth transmitting radio signals, opening the dawn of the space age.

Why are satellites divided into so many types?

Satellites are designed for a range of different purposes — communications, weather observation, positioning, Earth observation, scientific research, and more. Because the required orbital altitude and equipment differ depending on the purpose, satellites are operated in specialized categories by use.

Also explore the rockets that launch satellites into orbit

Getting a satellite into low Earth orbit or geostationary orbit requires the power of a powerful rocket. See our guide to how rockets are launched to explore the law of action and reaction and the principles behind multi-stage rockets.

Frequently Asked Questions

Why do geostationary satellites always seem to be in the same position?

A satellite orbiting in geostationary orbit, at an altitude of about 35,786 km, completes one orbit on a 24-hour cycle matching Earth's rotation, so from the ground it always appears fixed in the same position in the sky.

Which orbit do GPS satellites use?

Navigation satellites, including GPS, operate in medium Earth orbit (MEO) at an altitude of about 20,200 km, with multiple satellites deployed together so that at least 4 satellite signals can be received from anywhere on the ground.