Ubiquitous magnetic flux emergence in the Sun: a fundamental process

The fundamental process of magnetic flux emergence happens continuously and everywhere over the solar surface, hence the ubiquitousness. No matter which spatial (granular, supergranular, active region) and temporal scale we look at buoyant magnetic field coming from the convection zone pierces the photosphere in the form of two opposite polarities and travels upwards through the solar atmosphere. We will describe the general characteristics of magnetic flux emergence at different spatial scales from an observational point of view, as well as having a brief look at how numerical simulations can help us understanding the whole process. Why do we care?  Flux emergence at all scales continuously deposits energy and magnetic flux in the outermost layers of the Sun’s atmosphere, i.e. the transition region and the corona, and may be one of the prime contributors to the heating of these upper layers.