Morpho wings are covered in scales carved with microscopic ridges, spaced at the scale of light's wavelength. These structures reinforce blue and cancel the other colours: it is a structural colour. The proof: soak a wing in a liquid that fills those gaps and its shine fades, only to return as it dries.
Cooled below −183 °C, oxygen turns into a pale blue liquid. Pour it between the poles of a strong magnet and, instead of flowing away, it hangs suspended between them. The reason lies in its unpaired electrons, which respond to the magnetic field. Liquid nitrogen, by contrast, is colourless and pours straight through.
In 2012, Felix Baumgartner jumped from a capsule hanging beneath a balloon, about 39 kilometres up. In that extremely thin air almost nothing slowed him down, and he reached around 1,358 km/h in free fall, or Mach 1.25. He became the first person to exceed the speed of sound with nothing but his own body.