# Song, ‘Heavenly Stems and Earthly Branches’, 2024 > [!cite] > Song, Sophie. ‘Heavenly Stems and Earthly Branches: Origin and Charts’. Chinese New Year, last updated 27 September 2024. https://chinesenewyear.net/heavenly-stems-and-earthly-branches/. --- ‘The Ten Heavenly Stems once formed the ten days of the week thousands of years ago, before the more sophisticated lunar calendar came into being.’ [[Song, ‘Heavenly Stems and Earthly Branches’, 2024|(Song 2024c)]] ^b42a2d ’But to this day in China and other Chinese speaking countries, the Heavenly Stems are often used to denote orders, ratings and categories. For example, they are used in biochemistry to denote the numbers of carbon atoms a chemical compound contains.’ [[Song, ‘Heavenly Stems and Earthly Branches’, 2024|(Song 2024c)]] ^bcdb64 ‘… some historians believe the zodiac animals were designed to help people remember the order of the Earthly Branches.’ [[Song, ‘Heavenly Stems and Earthly Branches’, 2024|(Song 2024c)]] ^5a4793 ‘Even though the two systems of Heavenly Stems and Earthly Branches are almost always mentioned in the same breath these days, they evolved separately and were used in different ways in the beginning.’ [[Song, ‘Heavenly Stems and Earthly Branches’, 2024|(Song 2024c)]] ^b15f6d ‘Originally based on observations of the sky, these two counting systems later became very influential in many aspects of daily life in China, spreading beyond its borders to other parts of Asia.’ [[Song, ‘Heavenly Stems and Earthly Branches’, 2024|(Song 2024c)]] ^997105 The two systems of Heavenly Stems and Earthly Branches have been in use since ‘practically the beginning of recorded history in China in the Shang Dynasty.’ [[Song, ‘Heavenly Stems and Earthly Branches’, 2024|(Song 2024c)]] ^def01c ’Archaeologists found a piece of oracle bone dating back to 1000 BC, where the complete sexagenary cycle—composed of Heavenly Stems and Earthly Branches—had been carved.’ [[Song, ‘Heavenly Stems and Earthly Branches’, 2024|(Song 2024c)]] ^f85b5b ‘The Heavenly Stems and Earthly Branches are ancient China’s systems of keeping time. Originally based on observations of the sky, these two counting systems later became very influential in many aspects of daily life in China, spreading beyond its borders to other parts of Asia. These two systems are known for combining to designate years within a 60-year cycle in the traditional Chinese calendar, or a sexagenary cycle.’ [[Song, ‘Heavenly Stems and Earthly Branches’, 2024|(Song 2024c)]] ^a460e2