Light curve (relative flux vs time)
This 2D simulator recreates a transiting exoplanet from the observer's point of view: a planet orbits a glowing star and, whenever it passes in front of the stellar disk, blocks a sliver of starlight that shows up as a dip in the light curve below — the same signal real telescopes like Kepler and TESS use to detect worlds they can never directly image. Drag the planet-radius slider to see the transit depth grow with (Rplanet/Rstar)², tune the orbital speed to change the period, and tilt the inclination away from 90° to watch the impact parameter grow, the transit shorten and shallow, and eventually vanish once the planet's path clears the star's disk entirely.