Astronomy
Measuring the Solar System with Venus
Compare the same Venus transit from two observing sites. Their displaced tracks reveal solar parallax and the scale of the Solar System.
The model and its limits
Idealised parallel observer baseline and uniform solar discs; no limb darkening or terrestrial rotation. The astronomical unit is inferred from the two timed durations, so the black-drop effect enters as the clocks’ precision. The baseline is perpendicular to the tracks. Sun and observer views have separate scales.
Equations used in the module
Equations Δθ = B/AU [1/(1−0.723)−1]; duration = chord/angular speed.
