emission-line object

The term emission-line object is often used for sources that raise interest because they show a clear emission line or lines, particularly if the observed line is insufficient to identify the type of object. The term is often used for such objects discovered in surveys. Some surveys specifically search for objects some particular emission lines, to locate candidates for some such objects. Some of the types of objects that include emission lines:

• Be stars.
• emission line galaxies.
• emission-line stars.
• Herbig AeBe stars.
• Herbig-Haro objects.
• LINERs.
• planetary nebulae.
• Seyfert galaxies.
• shell stars.
• submillimeter galaxies.
• T-Tauri stars.
• Wolf-Rayet stars.