Orbital Mechanics
11 questions tagged Orbital Mechanics — spanning every one of the seven Ws.
What is a gravity assist in spaceflight?
A gravity assist is a maneuver that uses a planet’s motion and gravity to change a spacecraft’s speed and direction without much fuel. It is also called a slingshot maneuver.
What is the Sun-Earth L2 point?
The Sun-Earth L2 point is a stable-ish location about 1.5 million kilometers from Earth on the opposite side of the Sun. Spacecraft placed there can keep the Sun, Earth, and Moon mostly on one side.
What is orbital resonance?
Orbital resonance happens when orbiting bodies exert regular, repeating gravitational pulls on each other because their orbital periods are linked.
How does the International Space Station stay in orbit so low?
It continuously falls around Earth while moving sideways fast enough to miss the ground. Small reboosts are needed because atmospheric drag at its altitude still slows it down.
How do spacecraft use gravity assists to save fuel on long missions?
They fly past a planet and steal a tiny bit of its orbital momentum, changing speed and direction without much fuel. This technique has powered many deep-space missions.
What is the Roche limit?
The Roche limit is the distance where a moon or other body can be torn apart by a planet’s gravity.
What is a Lagrange point in the Solar System?
A Lagrange point is a place where the gravity of two large bodies and orbital motion balance so a smaller object can stay relatively stable.
Where is the center of mass of the Earth-Moon system located?
It lies inside Earth, about 4,670 kilometers from Earth’s center, or roughly 1,700 kilometers beneath the surface. This point is called the barycenter.
Whose equations described the motion of planets before modern computers?
Johannes Kepler’s laws described how planets move around the Sun. His work gave astronomers a precise mathematical model of planetary orbits.
Whose name is given to the spacecraft concept for traveling between planets using gravity assists?
The gravity-assist technique is often associated with Michael Minovitch, who worked it out in the 1960s. His calculations helped make efficient interplanetary travel possible.
Whose law explains why the solar system's planets speed up when they are closer to the Sun and slow down when farther away?
That is Kepler's second law, again from Johannes Kepler. It says a line from a planet to the Sun sweeps out equal areas in equal times.