Try circular speed
A launch multiplier of one starts with the circular speed at radius two.
Satellite Orbit Playground
Adjust tangential launch speed and step a satellite through a numerically integrated gravitational trajectory.
Grades 3–5 · Physics
Your goal
Launch for a nearly circular orbit and advance at least 5 steps. Each step follows up to two gravity time units.
Reduced motion is on. The controls still update the scene.
Flight in progress. Elapsed 0.00 gravity time units. Launch energy -0.460. Distance now 2.00 planet radii.
The satellite launches tangentially at radius 2. A velocity Verlet integrator follows inverse square gravity from a fixed spherical planet. Planet radius and gravitational parameter are 1, so circular launch speed is 0.707 and escape speed is 1 in these units. There is no air, thrust or other body. Each manual step integrates 100 small time intervals. Energy and the path determine orbit or escape.
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Learn with Satellite Orbit Playground
Satellite Orbit Playground lets elementary learners test how sideways speed changes a falling object’s path. Launch from the same height above a spherical planet, then advance small batches of gravitational motion. A slow satellite can hit the surface, a suitable speed produces an almost circular path, and other speeds make an ellipse or an escape trajectory. The trail comes from numerical integration of gravity rather than a selected picture. Compare launch energy, distance, and path shape while using a labeled distance scale that adjusts as the satellite travels.
What to look for
Step through the path
Each manual advance computes many small intervals of inverse square gravity.
Compare energy
A sufficiently fast launch has nonnegative orbital energy and can escape.
For teachers and curious learners
Connect launch speed with collision, circular motion, bound ellipses and escape under gravity. Ask students to predict what will happen, change one setting, and explain what they observe. Learn gives a starting point. Practice and Challenge offer new goals with the same scene.
A velocity Verlet integrator models a test satellite around a fixed spherical planet with radius and gravitational parameter equal to one. No air, thrust or other bodies. The display automatically zooms; time and distance use separate labeled units.