Betacoronavirus the Latin “corona” meaning crown or halo, referring to their image under electron microscopy of crown-like spikes on their surface similar to the solar corona. This morphology is created by the viral spike (S) peplomers, which are proteins that populate the surface of the virus and determine host tropism. The order Nidovirales is named for the Latin nidus, which means nest. It refers to this order’s production of a 3' co-terminal nested set of subgenomic mRNA's during infection. Betacoronavirus Betacoronaviruses are one of four genera of coronaviruses of the subfamily "Coronavirinae" in the family "Coronaviridae", of the order "Nidovirales". They
22° halo a 22° halo unreliable as a sign of bad weather. 22° halo A 22° halo is an optical phenomenon that belongs to the family of ice crystal halos, in the form of a ring with a radius of approximately 22° around the Sun or Moon. When visible around the moon, it is called a moon ring or winter halo. It forms as the sun- or moonlight is refracted in millions of hexagonal ice crystals suspended in the atmosphere. The halo is large; the radius is roughly the size of an outstretched hand at arm's length. A 22° halo may be