The latest Star Wars film, the Rise of Skywalker, has prompted one fan to look at how concrete has helped save the Rebel Alliance in this and other Star Wars films.
Alistair Marsh, writing on the website Quartz, says that on more than one occasion, the Rebel Alliance has retreated to fortified bases to escape annihilation by the Empire forces. He claims that concrete has played a pivotal role in the fate of the galaxy since rebel bases are built inside caves and have concrete flooring and ceilings.
Marsh looks at how the concrete could be used on sub-zero centigrade planets. Standard concrete will not set at below zero temperatures. When the Rothera research centre in Antarctica was upgraded, a special rapid-hardening cement was used that contained calcium aluminates. This reduces the time when the cement must be protected from freezing. The Rebel Alliance, he concludes, probably use similar quick-drying cement.
Another issue is that salt can corrode steel used to reinforce concrete. The collapse of the Morandi Bridge in Italy in 2018 may have been due to salt in the sea air affecting the bridge. The Rebels built a base on the high salt planet Crait, and Marsh believes that the concrete flooring and other structures would be safe as Crait is an extremely dry planet, and salt and humidity are required for corrosion.
Concrete is the second most used material on Earth after water. If Star Wars is anything to go by, it appears that this will continue to be the case in the distant future, even in far-off galaxies.