Material Science is Coming Up with Stuff that Can Survive Space

Space travel is happening today and will be very much a part of humanity’s future. Finding the right materials is therefore key. Our current best practices are evident in the materials used for the International Space Station (ISS) and satellites that service our planet and go out into the Solar System on voyages of discovery. Some materials handle a vacuum environment better than others. To give you a little bit of an idea about what engineers and scientists are already using in materials and may use in the future, we’ve compiled a list.

Aluminum

Perhaps aluminum’s most useful feature is that it’s simultaneously strong and remarkably lightweight. Aluminum on its own isn’t durable enough for use in space, but it’s a common additive when fabricators make alloys being used in space. Aluminum is added because it lowers the weight of finished products without sacrificing too much strength. For example, astronauts use aluminum alloy shutters on the ISS to protect the station from flying space debris.

Titanium and Titanium Alloys

Featured in jet aircraft, titanium is a lightweight metal that is used on its own and in alloys for space materials. There is lots of titanium in current space infrastructure both on the ISS, as well as on satellites. The Rosetta Project, an etched pure titanium plate today is mounted on the outside of the ISS and contains an archival record of Earth’s languages. Titanium can withstand the extreme hazards of space including temperature fluctuations, and cosmic and solar radiation.

Reinforced Carbon-Carbon Composite

Otherwise known as RCC, this material was essential in the U.S. shuttle program. It covered vital areas of the shuttle’s wing surfaces redistributing extreme heat upon re-entry into the atmosphere. It works like a complicated car radiator releasing heat. It was placed wherever extreme heat could affect the shuttle’s operation and redirected the heat away from more sensitive areas of the spacecraft. RCC is lightweight but also delicate. A piece of polyurethane foam insulation that broke off the external tank during the launch of the shuttle Columbia caused sufficient damage leading to the disaster in 2003 and the deaths of its seven-member crew. The successors to the shuttle, the X-37 military shuttle, and Sierra Nevada’s Dream Chaser, use a more advanced version of RCC called TUFROC (which is short for Toughened Uni-piece Fibrous Reinforced Oxidation-Resistant Composite).

Kevlar

Kevlar is a useful space material. You probably are aware of it in clothing designed to be durable. The military and law enforcement use kevlar vests to protect soldiers and police from bullets. In the same way it stops bullets, kevlar in space protects satellites, spacecraft and the ISS from pieces of junk and space debris floating around in Earth orbit. Kevlar is lightweight and durable. It can handle extremely hot and cold temperatures without warping.

Thermal Glass

The windows of the ISS, Dragon capsule and other space vehicles with humans on board are made of thermal glass. Regular glass would shatter in the space environment and wouldn’t be capable of handling launch or re-entry through the atmosphere. Thermal glass properties allow it to withstand the changing pressure as spacecraft make their way into and back from space. It withstands exceedingly hot and cold temperatures without cracking or breaking.

Silica cloth and silica aerogels

For areas on a spacecraft that need to be more flexible, silica cloth is commonly used. For example, the areas around the U.S. shuttle’s landing gear used silica cloth. While not the most durable material, it withstands the rigours of space travel without breaking down.

Silica aerogels were used in the U.S. shuttle, and currently are found on NASA’s Mars rovers, both Curiosity and Perseverance. Silica aerogels are similar in chemical structure to glass, and incorporate gas or air in their pores instead of liquid. The individual pores are less than 1/10,000th of the diameter of a human hair, just a few nanometers. The nanoporous nature of silicon aerogels gives the material the lowest thermal conductivity of any known solid.