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.
Turbulence causes the air within the lower atmospheric regions below the turbopause at about 110 km to be a mixture of gases that does not change its composition. Its mean molecular weight is 29 g/mol with molecular oxygen (O 2) and nitrogen (N 2) as the two dominant constituents.