▲ The hydrogen

In elementary school, everyone knows that all matter has three forms, and these are solid, liquid and gas.

Also, they know that the temperature can change the form of matter.

In middle school, we learn that pressure can change the form of matter. For instance, we use H2O to explain the change of form as water, ice, and steam.

Then, can we make hydrogen in a form of solid?

This curiosity made a magical theory 81 years ago. 

In 1935, scientist Eugene Wigner and Huntington made a theory that if we apply pressure to the hydrogen with 250K barometric pressure, we could make metal hydrogen.

However, there was no way to prove this theory because they could not make that high barometric pressure.

▲ Many scientist think that there are metal hydrogen due to high pressure and low temperature

Nonetheless, on January 27, 2017, Havard University made the first metal hydrogen in the world.The boiling point of hydrogen is -258°C.

Moreover, if we lower the temperature to -273°C, we can make liquid hydrogen. Harvard University did not stop and lowered the temperature to -267°C and apply pressure with 4950K barometric pressure. Then, the infinitesimal amount of metal hydrogen appeared.

Harvard used two very pointed diamonds and pressed hydrogen with the point of two diamonds.

▲ apply pressure with two diamonds

It is just a discovery of metal hydrogen. We cannot use it right now, but its future is still very bright. Maybe in the future, we can use metal hydrogen as we use fossil fuel today.