Coronavirus Coronavirus Coronaviruses are species of virus belonging to the subfamily "Coronavirinae" in the family "Coronaviridae", in the order Nidovirales. Coronaviruses are enveloped viruses with a positive-sense single-stranded RNA genome and with a nucleocapsid of helical symmetry. The genomic size of coronaviruses ranges from approximately 26 to 32 kilobases, the largest for an RNA virus. The name "coronavirus" is derived from the Latin "corona", meaning crown or halo, and refers to the characteristic appearance of virions under electron microscopy (E.M.) with a fringe of large, bulbous surface projections creating an image reminiscent of a royal crown or of the solar corona.
Collis (planetary nomenclature) Collis (planetary nomenclature) Collis (plural: colles, from the Latin word for "hill") is a small hill or knob on a celestial body. The term is used in planetary nomenclature: it is a part of international proper names of such features. Like other generic terms, it is capitalized and stands after the proper name (for example, "Bilbo Colles"; the only exception is "Colles Nili" on Mars). As of 2015, only groups of the hills have names, and the term is used only in plural. Like the other terms of planetary nomenclature, this word describes only external view of the features, but