Why Does the Moon Shine in the Daytime?
A poplar tree in full fall regalia frames the waning gibbous moon this morning. Bob King I've written about seeing the moon in the daytime sky before. I hope you don't mind if I take another swing at the topic. Did you see the moon this morning? Just amazing. It caught my eye around 8 a.m. high in the southwestern sky couched in deep blue and framed by autumnal colors. Portrait of the full moon if the sun's light were suddenly extinguished. Can you find it? Stellarium with additions by the author For the next two hours as I went about errands it hung in clear view opposite the sun, illuminated by the light kindled by fusing atoms in its core. At a glance you could see one of the most important differences between a planet (or moon) and a star. A star makes its own energy and beams it across space in all directions. Moons and planets reflect a small portion of that light back, which renders them visible. Otherwise they'd appear as black silhouettes against the stars. Th...