Guo Shoujing facts for kids

Quick facts for kids Guo Shoujing
郭守敬
Born	1231 Xingtai, Hebei province
Died	1314 or 1316
Known for	Shòushí Calendar (Chinese: 授时曆; literally "Season-Granting Calendar")
Scientific career
Fields	Astronomy, hydraulic engineering
Institutions	Gaocheng Astronomical Observatory

Guo Shoujing (Chinese: 郭守敬, 1231–1316) was a brilliant Chinese astronomer, engineer, and mathematician. He lived a long time ago, during the Yuan Dynasty (1271–1368). Many people think he was one of the greatest scientists in all of Chinese history. Guo Shoujing greatly helped science grow and develop.

He did many amazing things. He made the Grand Canal better, built a huge human-made lake called Kunming Lake, and created one of the most accurate calendars ever. He also invented some of the best clocks of his time. Plus, he made many other important contributions to math, astronomy, and hydraulics (which is about how water moves and is used).

Growing Up: A Young Genius

Guo Shoujing was born in 1231 in a place called Xingtai, in Hebei province. His family was not rich. His grandfather, Guo Yong, was famous for studying many subjects. These included the Five Classics, astronomy, mathematics, and hydraulics. Guo Shoujing was a child prodigy, meaning he was super smart from a young age.

When he was a teenager, he learned how to build a water clock. He then made it even better! His new invention was a special bowl shaped like a lotus flower. Water dripped into it to tell the time. At 16, he started studying math. From there, he moved on to learn about water engineering and astronomy.

How Did Guo Shoujing Improve Water Systems?

When he was 20, Guo became a hydraulic engineer and a government official. One of his first jobs was helping to fix a bridge. This bridge was over the Dahuoquan River.

Making the Grand Canal Better

In the late 1250s, Kublai Khan was the leader of the Mongol Empire and the Yuan dynasty. He believed that good water systems, like irrigation and water transport, would help his country and its people. So, he sent his advisor Liu Bingzhong and Liu's student, Guo, to improve the irrigation systems. These systems were between Dadu (which is now Beijing) and the Yellow River.

Guo helped build a 30-kilometer canal. This canal went from the Baifu spring in the Shenshan Mountain all the way to Dadu.

The Grand Canal was a very long waterway. It had connected the Yangzi river, the Huai, and the Yellow River since the early 7th century. Guo helped extend this canal to Dadu between 1292 and 1293.

His work was a big success. Kublai Khan was very pleased. Guo then did similar projects in other parts of the empire. He was promoted to a very important job. He became the chief advisor for hydraulics, mathematics, and astronomy.

Building the Human-Made Kunming Lake

One of Guo's most famous engineering achievements was creating a human-made Kunming Lake in Beijing. This was a huge project!

The lake provided water for all the areas around Beijing. It also helped create the best system in the world for transporting grain by water.

Guo also built other reservoirs (places to store water). This gave people in inner China access to fresh water. They used this water for planting crops, drinking, and trading goods.

For irrigation, he designed water systems that shared water equally and quickly. This helped communities trade more effectively and become richer.

In 1292, he became the head of the Water Works Bureau. This shows how important his work was.

What Inventions Did Guo Shoujing Create?

Guo Shoujing invented many tools for astronomy. These included the gnomon, the square table, the armilla, and a water-powered armillary sphere called the Ling Long Yi.

• The gnomon is like a clock. It tells time by measuring the sun's position, similar to a sundial. It can also figure out the seasons. Guo made this device much more accurate.
• The square table measures the angle and position of stars in the sky. It also works like a protractor.
• The armilla measures the angle of the sun. It can also find the position of any other object in space.
• The Ling Long Yi was a fancier and even more accurate version of the armilla.

How Did Guo Shoujing Improve Astronomy?

Even when he was young, Guo was changing old inventions. His clocks, watches, irrigation systems, and reservoirs were the most accurate of his time. This allowed for extremely precise recording of time.

Kublai Khan noticed that Guo was a genius in astronomy. So, he asked Guo, Zhang, and Wang Xun to build a very accurate calendar. This calendar would be the most accurate of its time. To collect data for their calculations, they built 27 observatories across the empire.

In 1280, Guo finished the calendar. He calculated a year to be 365.2425 days long. This is only 26 seconds different from modern measurements! He invented many tools while working on this project.

His calendar changed China and even influenced the world. It allowed for more accurate historical records. It also helped bring a sense of unity and helped later emperors rule China. Guo's calendar was used for the next 363 years. This is the longest any Chinese calendar has ever been used.

Guo was also able to figure out the exact location of celestial bodies (objects in space). He also calculated the angles of the Sun relative to Earth more accurately. He invented a new type of compass. This compass helped people find north using the stars instead of magnets.

In 1283, Guo was promoted to director of the Observatory in Beijing.

What Were Guo Shoujing's Contributions to Math?

Guo's work in mathematics was considered the most advanced for 400 years. Throughout his life, he worked a lot on spherical trigonometry. This is a type of math used for shapes on a sphere, like Earth. He used a way of estimating to find lengths of curves and angles. He estimated that pi was equal to 3. This allowed him to solve some equations much faster and more accurately than if he used 3.14... for pi.

He also used mathematical functions for spherical trigonometry. He built on the knowledge of Shen Kuo (1031–1095), another famous Chinese scientist.

The next important work in trigonometry in China was not printed until 300 years later. This was by Xu Guangqi in 1607, during the Ming Dynasty.

How Did Guo Shoujing Influence Others?

Tang Shunzhi (1507-1560), a later scholar, said that Guo's work was an example of "practical scholarship." This means applying advanced knowledge to solve real-world problems.

Guo also influenced a group of thinkers called the Changzhou School of Thought. He helped spread "evidential learning," which means learning through experience.

Many things are named after Guo to honor him. These include the Asteroid 2012 Guo Shou-Jing. There is also a very large telescope near Beijing called the Large Sky Area Multi-Object Fibre Spectroscopic Telescope.

Images for kids

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  The 27 observatories built and used by Guo Shoujing and his colleagues

See also

In Spanish: Guo Shoujing para niños