Editing Active galactic nucleus (section)

=== Relativistic jets ===
{{Main|Relativistic jet}}

[[File:M87 jet.jpg|thumb|upright=1| Image taken by the [[Hubble Space Telescope]] of a 5000-[[light-year]]-long jet ejected from the active [[galaxy M87]]. The blue [[synchrotron radiation]] contrasts with the yellow starlight from the host galaxy.]]

Some accretion discs produce jets of twin, highly [[collimated]], and fast outflows that emerge in opposite directions from close to the disc. The direction of the jet ejection is determined either by the angular momentum axis of the accretion disc or the spin axis of the black hole. The jet production mechanism and indeed the jet composition on very small scales are not understood at present due to the resolution of astronomical instruments being too low. The jets have their most obvious observational effects in the radio waveband, where [[very-long-baseline interferometry]] can be used to study the synchrotron radiation they emit at resolutions of sub-[[parsec]] scales. However, they radiate in all wavebands from the radio through to the gamma-ray range via the [[synchrotron]] and the [[Compton scattering|inverse-Compton scattering]] process, and so AGN jets are a second potential source of any observed continuum radiation.