» Home > In the News


7 December 2013

Albedo is derived from Latin = whiteness – in this instance it is reflected sunlight. From albus = white is the diffuse reflectivity or reflecting power of a surface (http://en.wikipedia.org/wiki/Albedo). Tim Cullen at http://malagabay.wordpress.com/2013/12/05/cosmic-ray-blues-lunar-luminos… … takes a look at different sources in order to get a handle on Albdedo – referenced in climate studies, the reflective nature of white snow (on the surface, particularly at the Poles). Albedo, reflection sunlight, is measured on a scale from zero (no relection) to 1 (perfect reflection from a white surface). Asteroid Eros is quite dark at 0.25 but the Moon is even darker at 0.12. He then says a Full Moon should therefore also be dark – bit it isn't. It's very bright – luminous in fact. What is going on?

We are at the point of his post now as the bright Moon is bright enough to have an albedo score of 1.0 (perfect). This is usually attributed to what is known as Earthshine, light from the day side of the Earth reflected on the night side of the Moon – but why is the whole of the Moon bright when it is full, so bright it shines through the bedroom window, outdoing the street lights. He then quotes liberally from the literature on earth shine – which can only reflect on one side of the Earth, and then adds 'the explanation if imaginative but it's pure moonshine …'. Brilliant.

The explanation for lunar luminosity, he says, are the cosmic rays that batter the surface. In this instance, gamma rays. These have been detected on the Moon and they trigger electromagnetic cascades which generate flourescent light. Lunar gamma rays are produced by a cosmic ray bombardment of the surface of the Moon – including lots of solar cosmic rays. Yet, mainstream science manages to lose them down the back of the sofa, he adds.

Skip to content