Adjective
substellar (not comparable)
(astronomy, of an object) Having a mass less than the minimum necessary mass for hydrogen fusion
a substellar companion
15 Sagittae is a solar analog that has a brown dwarf substellar companion. Source: Internet
In 1995, the study of brown dwarfs changed substantially with the discovery of two undisputable substellar objects ( Teide 1 and Gliese 229B ), citation citation which were identified by the presence of the 670.8 nm lithium line. Source: Internet
Therefore, the presence of the lithium spectral line in a candidate brown dwarf is a strong indicator that it is indeed a substellar object. Source: Internet
This fact is one of the lithium test principles used to judge the substellar nature of low-luminosity and low-surface-temperature astronomical bodies. Source: Internet
This is a result of the low temperature necessary to destroy lithium, and a lack of common processes to produce it. citation Lithium is also found in brown dwarf substellar objects and certain anomalous orange stars. Source: Internet