Astronomy Picture of the Day (APOD) is a website provided by NASA and Michigan Technological University (MTU).
The Caldwell Catalogue is an astronomical catalog of 109 star clusters, nebulae, and galaxies for observation by amateur astronomers.
New!!: S 155 and Caldwell catalogue ·
Cepheus is a constellation in the northern sky.
New!!: S 155 and Cepheus (constellation) ·
The Sharpless catalog is a list of 313 HII regions (emission nebulae), intended to be comprehensive north of declination -27°.
New!!: S 155 and Sharpless catalog ·