Low Earth Orbit (LEO)

Definition

Low Earth Orbit (LEO) refers to an orbit around Earth with an altitude ranging from approximately 160 kilometers (about 99 miles) to 2,000 kilometers (about 1,200 miles). Satellites in LEO experience lower gravitational forces and less atmospheric drag, allowing them to maintain their orbits more efficiently. This region is crucial for various applications, including telecommunications, Earth observation, and scientific research.

5 Must Know Facts For Your Next Test

1. LEO is typically defined as orbits between 160 km and 2,000 km above Earth's surface.
2. Satellites in LEO complete an orbit around Earth in about 90 to 120 minutes, which allows for frequent communication and data transmission.
3. The reduced distance from Earth in LEO makes it ideal for imaging satellites to capture high-resolution images of the planet's surface.
4. LEO is heavily populated with various satellites, including those for GPS, communication networks, and space stations like the International Space Station (ISS).
5. Due to atmospheric drag, satellites in LEO require periodic boosts to maintain their orbits and can have lifetimes ranging from several years to over a decade depending on their altitude.

Review Questions

• How does the altitude of Low Earth Orbit affect satellite operations compared to higher orbits?
  • The altitude of Low Earth Orbit significantly impacts satellite operations by allowing satellites to maintain lower gravitational forces and experience less atmospheric drag. This results in shorter orbital periods, enabling faster data collection and communication with ground stations. Additionally, satellites in LEO can achieve higher resolution imagery due to their proximity to Earth, which is beneficial for various applications like environmental monitoring and disaster response.
• Discuss the advantages and disadvantages of placing satellites in Low Earth Orbit versus Geostationary Orbit.
  • Placing satellites in Low Earth Orbit offers advantages such as reduced latency due to shorter distances for signal transmission and the ability to capture high-resolution images. However, they face challenges such as higher atmospheric drag and the need for frequent orbit adjustments. In contrast, Geostationary Orbits allow satellites to remain fixed over one point on Earth's surface but require a higher altitude that limits coverage area and leads to increased latency in communication.
• Evaluate the role of Low Earth Orbit in the future of satellite technology and space exploration.
  • The future of satellite technology and space exploration heavily relies on Low Earth Orbit due to its strategic advantages for launching new constellations of satellites. As technology advances, LEO enables innovations such as satellite-based internet services and real-time global surveillance systems. Moreover, the increasing number of small satellites being launched indicates a trend towards more agile and responsive capabilities in monitoring environmental changes and supporting scientific research, shaping our understanding of both our planet and beyond.

Related terms

Satellite: An artificial object placed into orbit around a celestial body, often used for communication, weather monitoring, or scientific exploration.

Geostationary Orbit:

A circular orbit located approximately 35,786 kilometers (22,236 miles) above Earth's equator where a satellite appears stationary relative to the surface of the Earth.

Orbital Inclination: The angle between the orbital plane of a satellite and the equatorial plane of the Earth, affecting coverage and data collection capabilities.