Sexagesimal in the context of "Metric unit"

Babylonian astronomy was the study or recording of celestial objects during the early history of Mesopotamia. The numeral system used, sexagesimal, was based on 60, as opposed to ten in the modern decimal system. This system simplified the calculating and recording of unusually great and small numbers.

During the 8th and 7th centuries BC, Babylonian astronomers developed a new empirical approach to astronomy. They began studying and recording their belief system and philosophies dealing with an ideal nature of the universe and began employing an internal logic within their predictive planetary systems. This was an important contribution to astronomy and the philosophy of science, and some modern scholars have thus referred to this approach as a scientific revolution. This approach to astronomy was adopted and further developed in Greek and Hellenistic astrology. Classical Greek and Latin sources frequently use the term Chaldeans for the philosophers, who were considered as priest-scribes specializing in astronomical and other forms of divination. Babylonian astronomy paved the way for modern astrology and is responsible for its spread across the Graeco-Roman empire during the 2nd-century Hellenistic Period. The Babylonians used the sexagesimal system to trace the planets' transits, by dividing the 360 degree sky into 30 degrees, they assigned 12 zodiacal signs to the stars along the ecliptic.

The zodiac is a belt-shaped region of the sky that extends approximately 8° north and south celestial latitude of the ecliptic – the apparent path of the Sun across the celestial sphere over the course of the year. Within this zodiac belt appear the Moon and the brightest planets, along their orbital planes. The zodiac is divided along the ecliptic into 12 equal parts, called "signs", each occupying 30° of celestial longitude. These signs roughly correspond to the astronomical constellations with the following modern names: Aries, Taurus, Gemini, Cancer, Leo, Virgo, Libra, Scorpio, Sagittarius, Capricorn, Aquarius, and Pisces.

The signs have been used to determine the time of the year by identifying each sign with the days of the year the Sun is in the respective sign. In Western astrology, and formerly astronomy, the time of each sign is associated with different attributes. The zodiacal system and its angular measurement in 360 sexagesimal degree (°) originated with Babylonian astronomy during the 1st millennium BC, probably during the Achaemenid Empire. It was communicated into Greek astronomy by the 2nd century BC, as well as into developing the Hindu zodiac. Due to the precession of the equinoxes, the time of year that the Sun is in a given constellation has changed since Babylonian times, and the point of March equinox has moved from Aries into Pisces.

Babylonian mathematics (also known as Assyro-Babylonian mathematics) is the mathematics developed or practiced by the people of Mesopotamia, as attested by sources mainly surviving from the Old Babylonian period (1830–1531 BC) to the Seleucid from the last three or four centuries BC. With respect to content, there is scarcely any difference between the two groups of texts. Babylonian mathematics remained constant, in character and content, for over a millennium.

In contrast to the scarcity of sources in Ancient Egyptian mathematics, knowledge of Babylonian mathematics is derived from hundreds of clay tablets unearthed since the 1850s. Written in cuneiform, tablets were inscribed while the clay was moist, and baked hard in an oven or by the heat of the sun. The majority of recovered clay tablets date from 1800 to 1600 BC, and cover topics that include fractions, algebra, quadratic and cubic equations and the Pythagorean theorem. The Babylonian tablet YBC 7289 gives an approximation of ${\displaystyle {\sqrt {2}}}$ accurate to three significant sexagesimal digits (about six significant decimal digits).

An order of magnitude of time is usually a decimal prefix or decimal order-of-magnitude quantity together with a base unit of time, like a microsecond or a million years. In some cases, the order of magnitude may be implied (usually 1), like a "second" or "year." In other cases, the quantity name implies the base unit, like "century." In most cases, the base unit is seconds or years.

Prefixes are not usually used with a base unit of years. Therefore, it is said "a million years" instead of "a megayear." Clock time and calendar time have duodecimal or sexagesimal orders of magnitude rather than decimal, e.g., a year is 12 months, and a minute is 60 seconds.

Numerical analysis is the study of algorithms that use numerical approximation (as opposed to symbolic manipulations) for the problems of mathematical analysis (as distinguished from discrete mathematics). It is the study of numerical methods that attempt to find approximate solutions of problems rather than the exact ones. Numerical analysis finds application in all fields of engineering and the physical sciences, and in the 21st century also the life and social sciences like economics, medicine, business and even the arts. Current growth in computing power has enabled the use of more complex numerical analysis, providing detailed and realistic mathematical models in science and engineering. Examples of numerical analysis include: ordinary differential equations as found in celestial mechanics (predicting the motions of planets, stars and galaxies), numerical linear algebra in data analysis, and stochastic differential equations and Markov chains for simulating living cells in medicine and biology.

Before modern computers, numerical methods often relied on hand interpolation formulas, using data from large printed tables. Since the mid-20th century, computers calculate the required functions instead, but many of the same formulas continue to be used in software algorithms.