Artwork depicting a so-called micronova. This is an entirely new phenomenon in astrophysics, reported by astronomers at the University of Durham in the UK. They are highly explosive events that occur in a subsclass of cataclysmic binaries called intermediate polars (IP). The systems consist of a compact, highly magnetic white dwarf stripping matter from a closely orbiting red dwarf partner. As the stolen material is funneled along magnetic field lines, it encounters the white dwarf's magnetic pole. There the gas is compressed, and a violent but localised fusion reaction takes place within the top 2-20 km of the white dwarf. They are distinguished from the more well-known nova eruptions is that micronova are limited to the base of the column of accreted gas, whereas nova eruptions originate at the boundary between the white dwarf's surface and a disc of accreted material.
