Ormeau 1
Moon
The physical nature of lunar rays has historically been a subject of speculation. Early hypotheses suggested that they were deposits of salt from evaporated water. Later they were thought to be deposits of volcanic ash or streaks of dust. After the impact origin of craters became accepted, Eugene Shoemaker suggested during the 1960s that the rays were the result of fragmented ejecta material.
Recent studies suggest that the relative brightness of a lunar ray system is not always a reliable indicator of the age of a ray system. Instead the albedo also depends on the portion of iron oxide (FeO). Low portions of FeO result in brighter materials, so such a ray system can retain its lighter appearance for longer periods. Thus the material composition needs to be factored into the albedo analysis to determine age.
Among the lunar craters on the near side with pronounced ray systems are Aristarchus, Copernicus, Kepler, Proclus, Dionysius, Censorinus, Glushko, and Tycho. Similar ray systems also occur on the far side of the Moon, such as the rays radiating from the craters Giordano Bruno, Necho, Ohm, Jackson, King, and the small but prominent Pierazzo.
North Ray and South Ray craters, each with a clear ray system, were observed from the ground by the astronauts of Apollo 16 in 1972. WIKIPEDIA
Moon
The physical nature of lunar rays has historically been a subject of speculation. Early hypotheses suggested that they were deposits of salt from evaporated water. Later they were thought to be deposits of volcanic ash or streaks of dust. After the impact origin of craters became accepted, Eugene Shoemaker suggested during the 1960s that the rays were the result of fragmented ejecta material.
Recent studies suggest that the relative brightness of a lunar ray system is not always a reliable indicator of the age of a ray system. Instead the albedo also depends on the portion of iron oxide (FeO). Low portions of FeO result in brighter materials, so such a ray system can retain its lighter appearance for longer periods. Thus the material composition needs to be factored into the albedo analysis to determine age.
Among the lunar craters on the near side with pronounced ray systems are Aristarchus, Copernicus, Kepler, Proclus, Dionysius, Censorinus, Glushko, and Tycho. Similar ray systems also occur on the far side of the Moon, such as the rays radiating from the craters Giordano Bruno, Necho, Ohm, Jackson, King, and the small but prominent Pierazzo.
North Ray and South Ray craters, each with a clear ray system, were observed from the ground by the astronauts of Apollo 16 in 1972. WIKIPEDIA