A newly revealed bow shock surrounds LS Pegasi, a well-studied cataclysmic variable (CV) star in the constellation Pegasus. This reddish arc of emission was discovered through deep imaging and analysis of archival H-alpha and OIII data, confirming early suspicions from wide-field sky surveys. The emission structure seen here is a bow shock — a shell of material shaped by the motion of the star through the interstellar medium.

LS Pegasi has been known as a variable star since 1935, but it wasn’t until 1988 that it was classified as a CV, a system where a white dwarf accretes matter from a companion. In August 2020, amateur astronomer Dana Patchick detected subtle nebulosity around LS Pegasi using VTSS and SHASSA data, leading to targeted observations and the confirmation of this shock feature. The discovery contributes to a growing list of CVs with extended emission structures, suggesting mass-loss events or wind interactions that persist on large scales.