UX Orionis is a variable star in the constellation of Orion. It is a Herbig Ae star, located about 1,000 light-years from Earth. At its brightest it is a magnitude 9.4 object, so it is too faint to be seen with the naked eye. UX Orionis is the prototype of the UX Orionis class of variable stars (often called "UXors"), which are young stellar objects that exhibit large (greater than 2.8 magnitude), irregular changes in visual-band brightness. UX Orionis was discovered by Henrietta Swan Leavitt.
UX Orionis is surrounded by a circumstellar disk, and the star's photometric variability appears to be caused by episodes during which the star is obscured by dusty material within the circumstellar disk.
↑Glebocki, R.; Gnacinski, P. (2005). "VizieR Online Data Catalog: Catalog of Stellar Rotational Velocities (Glebocki+ 2005)". VizieR On-line Data Catalog: III/244. Originally Published in: 2005csss...13..571G; 2005yCat.3244....0G. 3244. Bibcode:2005yCat.3244....0G.
↑Herbst, W.; Herbst, D. K.; Grossman, E. J.; Weinstein, D. (November 1994). "Catalogue of UBVRI Photometry of T Tauri Stars and Analysis of the Causes of Their Variability". Astronomical Journal. 108: 1906. Bibcode:1994AJ....108.1906H. doi:10.1086/117204.