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Image from Consolidated Lunar Atlas
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Ray Systems
The most conspicuous features near full Moon are the bright rays which radiate from Tycho, Copernicus, Kepler and many other young impact craters. Following Gene Shoemaker's analysis in the late 1950s we now know that crater rays are pulverized ejecta widely dispersed from craters formed by high speed impact and mixed with local material gardened by such ejecta. The two most important recent studies are The Origin of Lunar Crater Rays by Hawke and colleagues, and Optical Maturity of Ejecta from Large Rayed Lunar Craters by Grier and colleagues. Because rays age and disappear, typically within less than 1 billion years, rayed craters are the youngest on the Moon.
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Although there are obviously many rayed craters, lists of crater ray systems are not as common as they were 100 years ago. Thus, Here is a listing from Elger's classic book The Moon, published in 1895. Remember the directions E and W for this and other publications before 1960 are opposite of today's E and W!
OMAT - GRIER PAPER
Agrippa - Exhibits faint rays.
Apollonius - Among the hills S. of this, there is a small bright streak system
Aratus - A very conspicuously brilliant crater in the Apennines, with a smaller light-surrounded crater W. of it.Autolycus - Encircled by a delicate nimbus, throwing out four or five prominent rays extending toward Archimedes, Seen best under evening illumination.
Aristillus - The centre of a noteworthy system of delicate rays extending W. toward the Caucasus; and on the S. disappearing among the rays of Autolycus. They are tracable on the Mare Nubium near Kirch.
Aristoteles A - A light-surrounded crater in the Mare Frigoris, N.E. of Aristoteles.
Cleomedes A - (On the floor.) Surrounded by a nimbus and rays. Large crater A, on the E. has also a nimbus and rays.
Dionysius - A brilliant crater with a prominent, briight, eccentrically placed nimbus on a dark surface, on which distinct rays are displayed.
Einmart - There is a large white spot N.W. of this.
Eudoxus A - A light-surrounded crater W.of Eudoxus, with distinct long streaks, of which extends to the S. wall of Aristoteles.
Geminus - Is associated with a system of very delicate rays.
Godin - Exhibits faint rays.
Hypatia B - A very small bright crater on a dark surface: surrounded by a faint nimbus.
Littrow - A very bright light-spot with streaks, on the site of a little crater and well-know cleft E. of this ring-plain.
Macrobius - Two light-surrounded craters on the E. of this formation, the more northerly being the brighter.
Manilius - Surrounded by a light halo and streaks.
Menelaus - A brilliant object. It is traversed by a long ray from Tycho.
Plinius A - Is surrounded by a well-marked halo.
Posidonius Gamma - Among the hills E. of this formation a light spot resembling Linne, according to Schmidt. He first saw it in 1857, when it had a delicate black spot in the centre. Dr. Vogel observed and drew it in 1871 with the great refractor at Bothkamp. These observations were confirmed by Schmidt in 1875 with the 14-feet refractor at Berlin.
Proclus - A well-known ray-centre, some of the rays prominent on part of the Mare Crisium.
Romer - A light-surrounded mountain on the E.
Sulpicius Gallus - A light spot near.
Taquet - Has a prominent nimbus and indications of very delicate streaks.
Taruntius - Has a very faint nimbus, with rays, on a dark surface.
Theaetetus - A very brilliant group of little hills E. of this formation.
About 1/3 done - more to come!