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How Do Artificial Satellites Stay in Orbit?

Modern life relies heavily on artificial satellites. They provide many important services, including GPS, weather forecasting, Earth observation, and other forms of communication. Artificial satellites orbit Earth with remarkable accuracy, both around and at the planet. But how do these satellites maintain their orbit and avoid falling back to Earth or drifting off into space?


Artificial Satellites Stay in Orbit
Artificial Satellites Stay in Orbit (Created by Google Gemini)

Understanding Orbit: Balance Between Gravity and Motion


An orbit is characterized by being on a continual path of free-fall. The satellite is accelerating toward Earth because of gravity, while, at the same time, travelling at a horizontal speed has kept the satellite travelling horizontally enough that it does not crash into the surface.


The two forces in play are:


  • Gravitational force – pulls the satellite toward the centre of Earth.

  • Tangential velocity (horizontal speed) – causes the satellite to continue its horizontal travel.

  • In its stable orbit, the satellite is in a perpetual state of free-fall, continuously orbiting around Earth rather than falling straight down into the planet.


If the satellite slows down too much, gravity will win, and it will enter the atmosphere. If it speeds up too much, it will escape the pull of Earth's gravity.



Satellite Speed to Remain in Orbit


To maintain orbital reach, a satellite must have reached the velocity called orbital velocity.


Satellite and Orbital Velocity


  • Low-earth orbit (LEO) = 17,500 miles/hour (28,000 km/h)

  • Medium-earth orbit (MEO) = 8,700 miles/hour (14,000 km/h)

  • Geostationary orbit (GEO) = 6,900 miles/hour (11,000 km/h)


The orbital velocities listed above are the velocities at which the satellite will continue descending toward the surface of Earth, while at the same time, the planet's surface curves outward away from the satellite at the same velocity as its descent.


Types of Satellite Orbits


Different missions require different orbits. Each orbit is carefully selected based on altitude, inclination, and purpose.


  1. Low Earth Orbit (LEO)


  • Altitude Range: 160-2000 km

  • Applications: Earth Observation, Remote Sensing, International Space Station

  • Benefits: High Resolution, Reduced Latency

  • Drawbacks: Atmospheric Drag


  1. Medium Earth Orbit (MEO)


  • Altitude Range: ~2000-35786 km

  • Applications: GNSS Systems (GPS, Galileo, GLONASS)

  • Offers a balance between coverage and signal strength


  1. Geostationary Orbit (GEO)


  • Altitude Range: 35786 km

  • Applications: Weather, Communication, and Broadcasting

  • Preserving thus makes the satellite appear as a stationary object directly above the equator.


Why Satellites Don’t Need Constant Propulsion


Contrary to popular belief, satellites do not continuously fire engines to stay in orbit.

Once placed in orbit:


  • There is no significant air resistance.

  • Momentum keeps the satellite moving.

  • Gravity provides the centripetal force.


Small thrusters are only used for:


  • Orbit corrections

  • Station keeping

  • Attitude control

  • End-of-life deorbiting


How Drag Interferes With Satellites


Even in space, Earth’s atmosphere extends outward. In Low Earth Orbit, trace atmospheric particles create drag that slowly reduces a satellite’s speed.


Effects of Drag

  • Gradual altitude loss

  • Increased reentry risk

  • Requires periodic orbital boosts


The International Space Station and other satellites experience regular reboosts of their orbital altitudes to compensate for this drag effect.


The Role of Newton’s Laws of Motion


Satellites follow an orbital path defined by Newton's Laws of Motion; these laws include:


  1. Newton's 1st Law: A Body Will Continue to Move at Constant Velocity Unless Another Body Appears to Change Its Direction or Speed.

  2. Newton's 2nd Law: The Effectiveness of the Force Someone Exerts on a Body Is Equal to Its Mass Times Its Acceleration.

  3. Newton's Law of Universal Gravitation: The Force Between Two Bodies Depends on the Masses of Both Bodies.


The interaction between Velocity and Gravity Keeps Satellites in Their Stable Orbits.


How Satellites Are Placed Into Orbit


A Great Amount of Energy and Accurate Timing Are Necessary for Launching A Satellite Into Space.


Launch Procedures for a Satellite.


  1. A Rocket Lifts Off With A Satellite on Board, to a Height Above The Atmosphere.

  2. The Rocket Grows Gradually in Horizontal Velocity (as it gains height).

  3. The Satellite Is Ejected From The Rocket Once The Rocket Reaches The Correct Altitude & Speed for Orbital Placement.

  4. After Ejection, Last-Minute Adjustments are Made to Ensure Proper Orbital Trajectory and Speed.


Once the Correct Speed and Trajectory Are Achieved, a Satellite Remains in Its Stable Orbit Without Further Assistance.


Why Orbits Matter for Geospatial Applications


The satellite orbits that support geography-based applications such as GeoWGS84.com have a profound impact on:


  • How accurate is a positioning system is

  • How often does it take readings?

  • How consistently it provides those readings over time

  • How stable a datum and reference frame are.


All of the Global Navigation Satellite Systems (GNSS) are based upon very specifically defined, Earth-centered coordinate systems (such as WGS 84) that maintain GNSS' position relative to its satellite orbit.


It is through the continuing evolution of satellite technology that precise, accurate orbital modeling will continue to provide essential elements of mapping, positioning, and global data systems.


For more information or any questions regarding the satellites, please don't hesitate to contact us at


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