Two telescope plates, taken six months apart. One faint, cold brown dwarf has wobbled against the background stars. Find it and measure how far it jumped to work out how far away it is.
1Blink — hold Space or the Blink button to flip between Epoch A and B.
2Find — tap the reddish star that jumps. Wrong picks cost 150.
3Measure — drag from its A spot to its B spot. Distance = 1 / parallax.