Lunar Reconnaissance Orbiter Camera

the Moon and Humanity

the Moon Has Shaped Human Civilization in Ways Both Subtle and Profound

the Moon has been Earth's companion since the birth of the Solar System, 4.6 billion years ago. Ancient humans were captivated by the Moon's cycles as it changed position, shape and vanished from the sky for part of its 29-day cycle. Stone age peoples recorded the phases of the Moon in various ways, as the observation of the Moon gave them a way to count the passage of days and predict the arrival of the seasons. Activities key to the development of human civilization like agriculture and hunting absolutely depended on reliable timekeeping, so all human societies developed ways to determine the length of the year. We see evidence of this in places like Stonehenge, where the position of some of the stones seem to be related to lunar cycle. These calendar systems also dictated when the year should begin and how to divide the year into smaller units of time. In fact, although the modern Gregorian calendar is based on the solar year, the earliest calendars were all based on the lunar cycle.

Stonehenge in the United Kingdom

The Telescope Revolutionized Our View of the Moon

By the early 1600's, the invention of the telescope enabled the first crude maps of the Moon by Thomas Harriot and Galileo Galilei. These early maps hinted that the Moon's surface was complex, filled with mysterious light-colored highlands, dark lowlands, and odd circular features.

In 1664, English scientist Robert Hooke was the first to investigate the nature and origin of the circular features on the Moon. He made detailed observations and conducted experiments to explain their formation as the result of impacts or volcanic processes. Giovanni Basttista Riccioli, a Jesuit priest and academic, in 1651 published a naming for features on the Moon that is still largely in use today. Riccioli called the dark lowland areas "seas" or "mare" in Latin and named them after the mythological qualities that the Moon was thought to possess (for example, tranquility and fertility). He also named craters after well-known philosophers, religious figures, and scientists.

A comparison of Hooke's detailed drawing (left) of Hipparchus crater with a modern photo taken with a 61" telescope (Consolidated Lunar Atlas Sheet E10). This drawing was published in 1664 in his book Micrographia and is the first single feature drawn from the Moon.