To Scale

from a coin to the sun. how good is your eye?

stretch a ball, a whale, a rocket, the Moon and the Sun to their real size beside things you know

Drag up or down to size each thing beside one you know, in as many strokes as you like, then tap to measure. It springs to its true size over your guess and says how far off you were, in percent. Sizes from SPMCIL, the MCC, Bajaj, NOAA, UNESCO, ISRO and NASA.

Concepts: scale, ratios, measurement, perception, astronomy.

An interactive you play with one thumb, on Wundr.