Luna moth color is blue-green in the north and for the over-wintering generation in the central and southern states; second and third generation wing color has more of a yellow-green tint. Described and named "Phalena plumata caudata" by James Petiver in 1700, this was the first North American saturniid to be reported in the insect literature. The initial Latin name, which roughly translates to "brilliant, feather tail", was replaced when Carl Linnaeus described the species in 1758 in the tenth edition of Systema Naturae, and renamed it "Phalaena luna", later "Actias luna", with "luna" derived from Luna, the Roman moon goddess. The
Celestial sphere the equatorial coordinate system, the celestial equator divides the celestial sphere into two halves: the northern and southern celestial hemispheres. Because astronomical objects are at such remote distances, casual observation of the sky offers no information on their actual distances. All celestial objects seem equally far away, as if fixed onto the inside of a sphere with a large but unknown radius, which appears to rotate westward overhead; meanwhile, Earth underfoot seems to remain still. For purposes of spherical astronomy, which is concerned only with the directions to celestial objects, it makes no difference if this is actually the case