EYS18

EYS18 is an astronomical object designated as entry eighteen in the EYS catalog, a survey that catalogs young stellar objects in nearby star-forming regions. It is identified as a pre-main-sequence star showing a significant infrared excess, which is typically interpreted as evidence for a circumstellar disk.

Observational studies across multiple wavelengths have characterized EYS18 as a variable young stellar object with properties consistent with ongoing accretion. The spectral energy distribution rises toward longer wavelengths, and spectroscopy has detected emission lines such as H-alpha, indicating active gas in the system. Near-infrared and mid-infrared data support the presence of warm dust in the inner disk, while submillimeter observations reveal cooler dust in the outer disk portions and provide constraints on disk mass.

Distance estimates for EYS18 place it within the local population of star-forming regions, with fundamental parameters that vary across analyses. Typical interpretations place the object at subsolar mass, with an age on the order of a few million years, though precise values differ between studies. The disk appears to be in an evolutionary stage where planet formation processes could be underway, but no definitive planetary companions have been confirmed to date.

EYS18 figures in broader studies of protoplanetary disks and pre-main-sequence evolution, contributing to questions about disk lifetimes, accretion rates, and the early stages of planet formation. Continued multiwavelength monitoring and higher-resolution imaging are expected to refine its parameters and reveal finer disk substructures.

See also: EYS catalog, young stellar object, protoplanetary disk, Herbig–Haro objects.