When to Use the Transit-Timing Variation (TTV) 3D Explorer
Open the Transit-Timing Variation (TTV) 3D Explorer when you want a hands-on answer to how astronomers find a planet that has never once been seen transiting its own star, by watching the timing wobble it causes in a sibling planet's transits instead.
Sessions this explorer fits
Students and teachers introducing exoplanet-detection methods beyond the direct transit dip, readers curious how Kepler-19c was found despite never transiting, anyone wanting to see a real 2:1 orbital resonance or the tightest known planet spacing in action, and readers who want the "how do we know a planet is there if we cannot see it" question answered directly all get a direct answer here.
Sessions this explorer does not fit
Sessions this page does not fit are studying a single planet's own direct brightness-dip light curve in detail, which is on the Exoplanet Transit 3D Explorer - that page renders the direct transit signal one planet produces by itself, not the indirect timing wobble a second planet causes. Walk through the controls in the step-by-step guide.
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