A Romantic Interplay of Time and Space: The Astronomical Clock

In the vast universe, humanity seems to have been fascinated by time since ancient times, judging time by changes in sky color, the sun's position, or the length of shadows. Clever humans invented early timekeeping

tools such as sundials, water clocks, and fire clocks.

Among these, the astronomical clock stands out uniquely. It not only displays time but also celestial phenomena, including the positions of the sun and moon, the phases of the moon, and the night sky, magically integrating the concepts of time and space.

The difficulty of building an astronomical clock lies not only in its complex principles but also in the significant investment of manpower and funds required for its continuous maintenance. Therefore, many ancient astronomical clocks have become irreparable due to disrepair or the inability of later generations to decipher them. Fortunately, among the most famous astronomical clocks, this precious masterpiece in Prague, Czech Republic, still functions well today, accurately striking a clear and resonant chime every hour. The intricate astronomical phenomena and mechanical sculptures still move as smoothly as when they were first built.

This captivating astronomical clock (Orloj), contrasting sharply with the weathered, gray buildings behind it, shines brilliantly, drawing every visitor to its splendor. Even today, many locals make a special trip here to calibrate their watches.

The upper astronomical dial has three concentric circles, representing the Tropic of Capricorn, the Equator, and the Tropic of Cancer. Black, red, and blue areas represent the horizon, with different colors signifying daytime, dawn/dusk, and nighttime.

The ecliptic circle shows the sun's passage through the 12 constellations throughout the year, corresponding to the 72 sections of the outer circle, allowing for more precise determination of the sun's position. The central cross structure intersects with each of the 12 constellations, representing the four solar terms: spring equinox, summer solstice, autumn equinox, and winter solstice.

The sun pointer: Its 366-toothed gears indicate the sun's position on the ecliptic. A gold finger at the tip points

to the outermost Old Bohemian time circle, which also moves slowly at a 30° angle each year.

Moon Hand: The gears have 379 teeth. The moon takes 29 days and 13 hours to rotate once on its axis and 27 days and 8 hours to revolve around the sun. The moon has a black and white side, and its rotation and revolution create its phases.

Babylonian Time: The ancient Babylonians believed that each hour was governed by a specific planet, hence the name planetary time. It divided the time from sunrise to sunset into 12 equal hours.

Old Bohemian Time: This time system was prevalent in the Middle Ages. The 24 hours of the day were calculated from sunset, and this time was displayed on the outermost dial and indicated by gold fingers.

German Time: This is the modern method of timekeeping, introduced to Germany from Bohemia. It begins at midnight and is divided into two 12-hour periods. It is marked on a fixed Roman numeral dial and also indicated by gold fingers.

Built in 1410, this astronomical clock has undergone optimization, damage, repair, war, and near destruction. It has survived the vicissitudes of time and has been protected to this day, bearing witness to 600 years of changing times and glory, symbolizing mankind's exploration and pursuit of the vast universe and the unknown.