Sphere of influence (Hill)
This interactive simulator explores Sphere of Influence (Hill) in Astronomy & The Sky. r_H ≈ a (m/3M)^(1/3): schematic secondary orbit and Hill radius vs masses and a. Use the controls to change the scenario; watch the visualization and any graphs or readouts to connect the model with lectures, labs, and homework.
Who it's for: Best once you already know the basic definitions and want to build intuition. Typical context: Astronomy & The Sky.
Key terms
- sphere
- influence
- hill
- sphere of influence
- astronomy
How it works
Where a small body’s gravity can loosely hold onto satellites before the primary star’s tidal field takes over — a rule of thumb for mission design and moon stability.
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