Inside a magnet, countless tiny magnetic domains point the same way. Heat makes atoms jiggle and eventually scrambles that alignment. Above a critical temperature called the Curie point, the material stops being magnetised: around 770 °C for iron. Cooling down does not restore it on its own, unless it sits in a magnetic field.
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.