Space Technology

Space technology covers the rockets, spacecraft and supporting systems used to reach and operate beyond Earth's atmosphere. Its foundation is the launch vehicle, a rocket that carries a payload to orbit by burning propellant and expelling exhaust at high speed. To stay in orbit, a spacecraft must reach a very high speed so that its path curves around the planet rather than falling back; escaping Earth's gravity entirely to reach other worlds requires more energy still.

Once in space, vehicles serve many purposes. Satellites placed in orbit handle communications, navigation, weather observation and Earth imaging. Space probes are uncrewed craft sent to study the Moon, other planets, comets and asteroids, transmitting data and images back to Earth across great distances. Crewed spacecraft carry astronauts, and orbiting space stations allow people to live and work in space for extended periods, conducting research in the weightless environment.

These efforts are organised largely by national and international space agencies. The United States agency NASA and the European Space Agency (ESA) are among the most prominent, alongside others operated by Russia, China, India, Japan and additional nations, with private companies playing a growing role. Historic milestones include the launch of the first artificial satellite, the first human spaceflight, and the Apollo programme that landed astronauts on the Moon. Space technology has also produced practical benefits on Earth, from satellite navigation to global communications and improved weather forecasting.

Frequently asked questions

How does a rocket reach orbit?

It burns propellant to accelerate to a very high speed, fast enough that its curved path around Earth matches the planet's curvature so it keeps falling around rather than back to the surface.

What is the difference between a satellite and a space probe?

A satellite orbits Earth for tasks like communication or imaging, while a space probe is sent away from Earth to study the Moon, planets or other distant bodies.

What do NASA and ESA do?

They are space agencies that design, launch and operate spacecraft and missions; NASA is the United States agency and ESA is the European Space Agency.