Space-grown protein crystals. Polarised light micrograph of crystals of an assortment of proteins that were grown in microgravity conditions in orbit. The proteins include mouse antibodies, fungal enzymes and viral proteins. The crystals were grown from aqueous solutions. They are useful in X-ray diffraction studies. This is a process in which X-rays are shone through a sample to determine its atomic structure. Even a small flaw in a crystal can render the technique useless. Crystals grown in microgravity tend to be less flawed than those grown on Earth.