MTL meaning in Space Science ?

A material is a substance or mixture of substances that constitutes an object. Materials can be pure or impure, living or non-living matter. Materials can be classified based on their physical and chemical properties, or on their geological origin or biological function. Materials science is the study of materials and their applications.

Raw materials can be processed in different ways to influence their properties, by purification, shaping or the introduction of other materials. New materials can be produced from raw materials by synthesis.

In industry, materials are inputs to manufacturing processes to produce products or more complex materials.