The series premiered on demand on November 23, 2015, and on Syfy on December 14, 2015. A 13-episode second season premiered on February 1, 2017. In March 2017, Syfy renewed The Expanse for a 13-episode third season to air in 2018.
Perlite is an amorphous volcanic glass that has a relatively high water content, typically formed by the hydration of obsidian.
Peridotite is a generic name used for coarse-grained, dark-colored, ultramafic igneous rocks. Peridotites usually contain olivine as their primary mineral, frequently with other mafic minerals such as pyroxenes and amphiboles. Their silica content is low compared to other igneous rocks, and they contain very little quartz and feldspar.