Taurus (constellation) is a white, spectral class B7 III giant star known as "El Nath", which comes from the Arabic phrase "the butting", as in butting by the horns of the bull. At magnitude 1.65, it is the second brightest star in the constellation, and shares the border with the neighboring constellation of Auriga. As a result, it also bears the designation Gamma Aurigae. Zeta Tauri (the proper name is "Tianguan") is an eclipsing binary star that completes an orbit every 133 days. A degree to the northwest of ζ Tauri is the Crab Nebula (M1), a supernova remnant. This expanding nebula
Eridanus (constellation) is depicted in ancient sky charts as a flowing river, starting from Orion and flowing in a meandering fashion past Cetus and Fornax and into the southern hemispheric stars. Johann Bayer's Uranometria depicts the river constellation as a flowing river. According to one theory, the Greek constellation takes its name from the Babylonian constellation known as the Star of Eridu (MUL.NUN.KI). Eridu was an ancient city in the extreme south of Babylonia; situated in the marshy regions it was held sacred to the god Enki-Ea who ruled the cosmic domain of the Abyss - a mythical conception of the fresh-water