NGC 1554
NGC 1554, Struve's Lost Nebula, is a list entry in the New General Catalogue of Nebulae compiled by John L. E. Dreyer. The nebula was discovered by the German-Russian astronomer Otto Wilhelm von Struve and confirmed by Heinrich Louis d'Arrest.
Dreyer describes it as
which in NGC's encoding is expanded to
' relative to NGC 1555
The identification is uncertain; many sources think it is related to NGC 1555, Hind's Variable Nebula'', but at NGC 1554's coordinates, there is no nebula. However, there is a 14th magnitude star, 4' west-southwest of T Tauri. So there's a possibility that the nebula Struve discovered was surrounding a variable star and it only flares up every now and then.
