What is a satellite?
A satellite is a space object that orbits a larger body, such as a planet or a star.
What is the difference between a natural and an artificial satellite?
There are two different types of satellites:
- natural satellites, like the Moon around Earth
- artificial satellites, like man-made objects that orbit Earth
Most often, when we talk about satellites, we are referring to artificial satellites.
The M3MSat (left) and Envisat (right) satellites. The size of the satellites can be seen when comparing them with the scientists standing next to them. (Credits: Defence Research and Development Canada and the European Space Agency)
How big are satellites?
Satellites can be as small as an oven or as big as a bus. They also come in a variety of shapes, depending on their mission and use.
What are the components of a satellite?
To function, satellites need essential elements:
- a solid envelope to withstand the rigours of launch and space
- an energy source, such as a battery or solar panels
- a scientific instrument for collecting data
- an antenna to send and receive information
What types of data are collected by satellites?
Satellites can collect or relay different types of data:
- radio waves
- microwaves
- infrared rays
- light
- ultraviolet rays
- X-rays
- gamma rays
Discover the various types of satellites.
What do satellites do in orbit?
All satellites have missions or roles to play, such as:
- observing and taking images of Earth
- exploring the universe (e.g., planets, stars, exoplanets, asteroids)
- transferring radio, television, and Internet signals
- transmitting a geolocation signal
Discover the use of satellites in our everyday lives.
What is a satellite's service life?
Nowadays, satellites must have an end-of-mission plan. When a satellite's mission is over, the satellite re-enters the atmosphere and disintegrates so as not to become space debris. This must happen no later than 25 years after the beginning of the mission.