Hafnium is named after Copenhagen and as it has a very high melting point it was used in the thruster nozzles of the Apollo Lunar modules, according to Elemental's Allan Blackman from AUT.

Hafnium is named for Hafnia, the Latin name of Copenhagen.

Ceramics that contain the transition metal hafnium (atomic number 72, symbol Hf) are among the highest melting substances known.

The metal itself melts at 2230 degrees celsius, while hafnium carbide melts at 3200 degrees celsius. This makes it useful in plasma torches used to cut steel.

Professor Allan Blackman from AUT says that a niobium-hafnium-titanium alloy also has a high melting point, which is why it was used in the thruster nozzles of the Apollo Lunar Modules.

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