// ORBITAL LOGISTICS AND PROPULSION TERM
Semiminor Axis
Half of the shortest diameter of an elliptical orbit, perpendicular to the semimajor axis.
TECHNICAL DEFINITION
The semiminor axis (b) is half the shortest diameter of an elliptical orbit, perpendicular to the semimajor axis and passing through the center of the ellipse, defining the shape of the ellipse in conjunction with the semimajor axis and eccentricity.
SYNONYMS & ALIASES
- Minor axis half
- 'b' parameter
USAGE NOTE
While less directly related to orbital period than the semimajor axis, the semiminor axis helps define the overall shape of an elliptical trajectory.
DEVELOPERS
Organizations developing technology related to Semiminor Axis.
Designs, manufactures, and launches advanced rockets and spacecraft. Their work in satellite deployment, orbital transfers, and maintaining large constellations like Starlink relies heavily on understanding and manipulating orbital mechanics, including parameters such as the semiminor axis for precise orbit determination.
As the U.S. government agency responsible for space programs, NASA's missions across planetary exploration, Earth observation, and human spaceflight extensively involve orbital mechanics, trajectory design, and mission planning where the semiminor axis is a fundamental orbital element.
ESA conducts space science, Earth observation, navigation, and human spaceflight missions. Their work in mission analysis, satellite operations, and space situational awareness requires deep knowledge of orbital parameters, including the semiminor axis, for accurate trajectory prediction and control.
A major defense and aerospace company, Lockheed Martin develops and builds a wide range of satellites, launch systems, and deep-space probes. Their engineering for orbital insertion, station-keeping, and spacecraft maneuvering is directly tied to orbital mechanics principles, using terms like semiminor axis to define orbits.
Developing reusable rockets, engines, and in-space systems for a future where millions of people live and work in space. Accurate orbital mechanics, including the calculation and management of orbital parameters like the semiminor axis, is critical for their launch services and space habitat development.
A global aerospace and defense technology company, Northrop Grumman designs, develops, and builds various space systems, including satellites and launch vehicles. Their work involves complex orbital analysis for mission success, where parameters like the semiminor axis are essential for defining and controlling spacecraft trajectories.
Known for its Electron launch vehicle and Photon satellite platform, Rocket Lab provides end-to-end space mission services. Precise orbital insertion and spacecraft deployment require sophisticated understanding and control of orbital elements, with the semiminor axis being a key factor in defining the achieved orbit.