I have a habit, when I wake up some nights, to get up and go down to read. Last night was notable because I could see the moon as a mere horn repeatedly swallowed and then reborn from the passing clouds. Through binoculars, however, I could make out the other portion of the entire lunar sphere as a kind of dimly lit distraction.
It was Leonardo da Vinci who first suggested that this shadowy part of the crescent moon is visible as a result of sunlight bouncing off Earth and then being re-emitted to our one satellite. It was amazing to think that the energy received here, even though I was standing and watching, was offered out there again a little more than a second later. This is because light travels at a speed per second roughly similar to our distance from the moon (the respective figures are about 300,000 km/sec and an average of 384,400 km).
The fact that the gap between our planet and our satellite varies depending on the lunar orbit appeared last month in that fantastically magnified sphere we call a hunter’s moon. I consider the name a rather sad reflection on our species, as the last thing it inspired was a wish to kill. Rather, it evoked the interconnectedness of planet, satellite and star in all life’s processes.
On that particular night, I also got up to read, and suddenly I was aware of silver moonlight flooding the back bedroom. It arrived in a narrow lozenge at the window, but then pooled over our Welsh blanket as intense color bathed in ethereal whiteness. Remember that the light took its customary second to come from the moon. However, the gamma rays that first gave birth to that energy in the core of the sun, where the atmosphere is 13 times the density of lead, can take thousands of years to rise through the intervening plasma to reach our star’s surface. The resulting photons then travel to Earth – here as moon-bent light – in just eight minutes, but the entire process involved in that momentary vision may be as old as our species. Our world is truly, in Henry Williamson’s words, a chronicle of ancient sunlight.
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