CHILLY CHAMPS
Here are some of the coldest record holders in existence
A conceptual illustration of a helium atom
THE COLDEST MELTING POINT
Helium takes the crown for the element with the lowest melting point in the known universe at a freezing -272.2 degrees Celsius, which is only a 0.95-degree separation from absolute zero. The melting point of an element is the energy required to transform a substance from a solid into a liquid. Helium gets its low melting point from its weak intermolecular forces and the small amount of interaction that occurs between each atom of helium. This means that it can be used as a cooling medium for particle accelerators and superconducting magnets.
A tardigrade, also known as a water bear
THE COLDES T LIVING THING
Tardigrades are some of the strangest and toughest living creatures in existence. Also known as water bears or moss pigs, tardigrades are small invertebrates that measure around 0.05 to 1.2 millimetres in length. One of the things that makes them unique is their ability to survive in the most extreme conditions – they can be found in almost every habitat on Earth. Researchers have discovered that these hardy creatures can survive at temperatures as low as -200 degrees Celsius. Tardigrades do this by entering into a death-like state known as cryptobiosis. While in this state, they expel more than 95 per cent of the water in their bodies. Their bodies are then protected by proteins that form a glass-like cocoon around each of their cells. Tardigrades can also revive themselves, even after decades of cryptobiosis slumber.