light echo (Q1823351)

physical phenomenon caused by light reflected off surfaces distant from the source, and arriving at the observer with a delay relative to this distance;analogous to an echo of sound, it mostly only manifests itself over astronomical distances

Language	Label	Description	Also known as
English	light echo	physical phenomenon caused by light reflected off surfaces distant from the source, and arriving at the observer with a delay relative to this distance;analogous to an echo of sound, it mostly only manifests itself over astronomical distances