Read the Moon.
Look, then look again.
Two named places, three things to notice and the line between day and night. Turn the globe to explore; it never turns by itself. Turning it is not the phase in tonight’s sky: for that, open the Moon notebook.
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The dark patches are lunar maria, “seas” in Latin, but there is no water: they are plains of old basaltic lava. They are not Earth’s seas, and they do not move the tides. Apollo 11 landed near its southern edge in 1969.
Try: on a clear night, find the dark patches with the naked eye.
Marker: IAU/USGS Gazetteer, feature 3691, 8.35° N, 30.83° E (an older record gives 8.50° N, 31.40° E). IAU/USGS record coordinates, east-positive; no conversion applied.
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An impact crater about 85 km across. Around full moon its bright rays run across much of the side we see. Bright rays usually mean a younger crater.
Try: near full moon, with binoculars, look towards the southern part of the lunar disc for a bright point with lines running out from it.
Marker: IAU/USGS Gazetteer, feature 6163, 43.30° S, 11.22° W (another control network gives 43.31° S, 11.36° W). IAU/USGS record coordinates, east-positive; no conversion applied.
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The lighter ground is highland crust, older and more heavily cratered than the maria. There is no single point to mark: it covers most of the Moon, including almost all of the far side.
Try: compare light and dark areas. Light is older ground; dark is later lava.
NASA Moon overview; LROC. No marker on purpose.
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The whole surface is covered by regolith: fine dust and broken rock made by billions of years of impacts. Apollo boot prints were pressed into it. It is everywhere, so it has no marker here.
Word: from Greek rhêgos, blanket, and líthos, stone.
NASA, Apollo lunar samples; LSJ s.v. ῥῆγος, λίθος.
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The terminator is where the Sun is rising or setting on the Moon. It moves all month. Along it, long shadows make craters easiest to see through binoculars or a telescope. The dashed line on the globe is computed for the day you choose with the Light slider.
Try: near first or last quarter, look along the straight edge of light.
Geometry from the mean synodic month (29.53 days), counted from the new moon of 9 November 2026, 07:02 UTC (USNO). Libration ignored: an approximation.
An illustrated cut, not an X-ray
A drawing of what scientists infer, partly from seismometers left by Apollo astronauts: a crust, a thick mantle and a small core. Sizes are indicative.
Sources listed on Sources.
Surface image: NASA’s Scientific Visualization Studio, CGI Moon Kit (SVS 4720); visualizer Ernie Wright (USRA), scientist Noah Petro (NASA/GSFC); dataset LROC WAC colour mosaic, Arizona State University. Reduced to 1024 × 512 for this page. NASA notes that this map is optimised for aesthetics, not science; for measurement use the LROC WAC data. Its use here does not imply endorsement by NASA. Place names and coordinates: IAU Gazetteer of Planetary Nomenclature (USGS). The globe is an orthographic view drawn in your browser.