In between the clouds

The Moon is Earth’s only natural satellite, with a mean distance of about 384,400 km and a diameter of 3,474 km. Its surface is dominated by bright, heavily cratered highlands and darker basaltic plains called maria, formed by ancient volcanic flooding. The lunar surface is about 4.5 billion years old, with many visible landforms preserved because the Moon lacks wind, rain, and active plate tectonics.

At 65% illumination, this is a waxing gibbous Moon, between first quarter and full phase. The terminator — the line dividing the lit and unlit halves — lies across the western near side and marks where low-angle sunlight emphasizes relief in craters, mountain ranges, and mare margins. Around this phase, prominent near-side maria such as Mare Imbrium, Mare Serenitatis, Mare Tranquillitatis, and Mare Fecunditatis are typically well illuminated, while terrain closer to the terminator shows the strongest shadows. The Moon’s apparent diameter is about half a degree, varying slightly with its elliptical orbit, and its brightness at this phase is roughly magnitude −11 to −12.