In the 1860s, James Clerk Maxwell unified the laws of electricity and magnetism in a handful of equations. They predicted electromagnetic waves, whose speed he calculated from constants measured in the lab with coils and capacitors. The answer matched the speed of light. The conclusion: light is an electromagnetic wave, just like radio and wifi would later turn out to be.
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.