Space Physics Flashcards
Space-Time
A four-dimensional continuum that blends the three dimensions of space with time, where events are described by both spatial coordinates and the time they occur.
Orbital Mechanics
The branch of physics that deals with the motion of objects in space under the influence of gravitational forces, used to calculate trajectories and velocities of spacecraft.
Kepler’s Laws
A set of three principles describing the motion of planets and other celestial bodies in orbit, providing the foundation for orbital mechanics.
Escape Velocity
The minimum velocity required for an object to break free from a celestial body’s gravitational pull without further propulsion.
Orbital Period
The time it takes for a spacecraft or celestial object to complete one full orbit around another body, such as the Earth or the Sun.
Gravity Assist
A technique where a spacecraft gains speed by using the gravitational field of a planet or moon, allowing it to reach destinations further in space with less fuel.
Inclination
The angle between the plane of an object’s orbit and the plane of Earth’s equator, which determines its coverage area and mission focus.
Aphelion
The point in an object’s orbit where it is farthest from the Sun.
Perihelion
The point in an object’s orbit where it is closest to the Sun.
Orbital Insertion
The process of placing a spacecraft into a stable orbit around a celestial body, often using propulsion systems to adjust its speed and trajectory.
Orbital Transfer
A maneuver used to change from one orbit to another, often through a series of carefully calculated velocity changes.
Tidal Forces
The gravitational forces exerted by a larger body on a smaller one, causing deformation and affecting the motion of the smaller body in space.
Relativity
A theory in physics developed by Einstein, explaining how the laws of physics are the same for all observers and how time and space are intertwined in the presence of gravity.
Time Dilation
A concept from relativity where time appears to pass at different rates depending on the relative velocity or gravitational field experienced by an observer.
Geostationary Orbit
A circular orbit around Earth 35,786 km above the equator where satellites appear stationary relative to the Earth’s surface.
Synodic Period
The time it takes for a celestial object to return to the same position relative to the Sun, such as the time between successive new moons.
Orbital Decay
The gradual decrease in the altitude of a satellite’s orbit due to atmospheric drag or gravitational interactions, eventually leading to reentry.
Space Debris
Non-functional objects, including defunct satellites, spent rocket stages, and other debris, that remain in orbit and pose a hazard to operational spacecraft.
Solar Wind
A stream of charged particles (mostly electrons and protons) emitted by the Sun, which can affect the motion of spacecraft and the space environment.
Electromagnetic Radiation
Energy emitted in the form of electromagnetic waves, including light, radio waves, X-rays, etc., that travels through space and can be detected by space-based instruments.
Interstellar Space
The vast region between star systems, where space is almost a perfect vacuum and conditions are vastly different from those found within solar systems.
Lagrange Points
Five positions in space where the gravitational forces of two large bodies (such as Earth and the Moon or Earth and the Sun) and the centrifugal force of an object balance each other, allowing a spacecraft to remain in a fixed position relative to those bodies.
