The Naked-Eye Sky
Our eyes can make out many different objects in the night sky, including bodies in the Solar System, stars in our own galaxy, and even neighbouring galaxies.
What do our eyes reveal?
[edit | edit source]On a clear evening, the night sky appears as a sparkling dome of stars stretching from horizon to horizon. Away from the lights of towns and cities, a deeper level of this majestic nightscape is revealed, with the myriad stars of our galaxy, the Milky Way, creating a glowing, misty band across the sky. There are transient characters too in this nightly show: the fleeting streak of a shooting star, or the occasional delicate shimmer of an aurora. Then there are the planets, our companions in space. They slowly wander across the background firmament as they orbit the Sun. The Moon is frequently present in the night sky. Its bright light can often wash out the fainter stars, but it is itself a fascinating object to observe, covered in smooth, dark "seas" as well as cratered and mountainous regions.
The constellations
[edit | edit source]Over time, humans have invented narratives to explain the patterns seen in the stars. These patterns are said to represent characters or objects from a mixture of ancient and relatively modern mythologies. Today the night sky is divided up by astronomers into 88 official areas, known as the constellations, each with its own demarcated boundaries. Stars located in the same constellation are not necessarily near each other - these groupings are just a convenient way to identify a particular area of sky.