400-year-old Lunar mystery solved ?

Columbia astronomy professor Arlin Crotts thinks he has solved a 400-year-old mystery: the origin of strange optical flashes often reported as appearing on the moon's surface. Transient Lunar Phenomena (TLPs), in which the lunar surface reportedly changes in brightness, blurriness or color, have been photographed and observed by thousands of astronomers over the centuries. Yet explanations of why they occur and even their reality as true lunar phenomena have been hotly debated. The TLPs typically cover a space of a few kilometers and last for several minutes. Crotts has uncovered a strong statistical relationship between TLPs and so-called outgassing events on the lunar surface. Outgassing occurs when gases trapped beneath a moon or planet are released and, if only briefly, become part of the object's atmosphere. A key component of this gas is radon.

"People over the years have attributed TLPs to all sorts of effects: turbulence in Earth's atmosphere, visual physiological effects, atmospheric smearing of light like a prism, and even psychological effects like hysteria or planted suggestion" says Crotts, "but TLPs correlate strongly with radon gas leaking from the moon. No earth-bound effect can fake that."