Space 01
How gravity assists speed up or slow down a spacecraft
Resolve the gravity-assist puzzle by comparing planet-relative and Sun-relative velocities during a simplified Jupiter flyby.
orbits
Space 02
Lagrange points explained: the geometry behind JWST and Aditya-L1
Understand the five rotating-frame equilibrium points, why L1 and L2 need station keeping, and what makes L4 and L5 different.
Space 03
Orbital resonance and repeating alignments: what a period ratio tells you
Explore 2:1 and 3:2 orbital rhythms, calculate radius ratios with Kepler’s law, and learn why a simple period match does not prove dynamical resonance.
Space 04
Why moons break apart: the Roche limit and planetary rings
Follow a density-based worked example of the Roche limit, then test when an icy or rocky moon crosses a tidal-disruption boundary.
Space 05
Why planets seem to move backward: retrograde motion explained
Use Earth’s moving viewpoint to explain Mars, Mercury and Venus retrograde motion, with a worked synodic-period example.