Plant diseases can be infectious (transmitted from plant to plant) or noninfectious. Noninfectious diseases are usually referred to as disorders. Common plant disorders are caused by deficiencies in plant nutrients, by waterlogged or polluted soil, and by polluted air.
Such refinements in the images of Betelgeuse's atmosphere has been helping to resolve the mystery of how massive amounts of dust and gas are expelled from red supergiant stars, an important source of enrichment for the interstellar medium.
Dec. - 7 degrees, 24'. Since Betelgeuse is north of the ecliptic, the declination is a positive value. Betelgeuse is at b, but the brightest star in Orion is Rigel, which is elsewhere. Bayer didn't always get his letters straight, or possibly one of the two has changed since then. In this case Î² Orionis is brighter than Î±.