Society for Popular Astronomy

The Moon – our close neighbour

The Moon is one of the easiest and most satisfying objects to observe. We are able to see more detail on its surface than any other body.

Because it is our close neighbour in space, the smallest telescope, or even binoculars, are enough to spot its craters and mountain ranges.

In fact you can see the Moon’s waterless seas – plains flooded with lava, and called maria – with just your eyes.

The waning Moon photographed by Paul Sutherland through a small telescope.

The Moon always keeps the same face pointed towards us, because it is tidally locked to the Earth. (In fact, due to a gentle rocking called libration, we see a little way over different limbs of the Moon at different times.)

The Moon shines by reflecting sunlight, just like the planets. So it goes through phases as it orbits the Earth. Shadows cast by the mountains and crater walls help these features stand out when you view them through a telescope.

At Full Moon, when the Sun is shining straight down on the Moon, the shadows disappear from our viewpoint and so does the detail!

Many SPA members enjoy sketching or photographing the Moon and sharing their observations. Join the SPA and you could be part of the Lunar Section too!

Click to visit the Lunar Section