science

Tiangou

Tiangou is a science topic covered in the lgStudy science library. This page brings together a partial reference excerpt, illustrations, worked examples, real-world applications and a short study plan, so you can understand Tiangou rather than just read about it. In short: The tiangou (Chinese: 天狗; pinyin: tiāngǒu; Wade–Giles: t'ien1-kou3; lit. 'Heavenly Dog') is a legendary creature from China. The tiangou resembles a black dog or meteor, and is thought to eat the Sun or Moon during an eclipse.

Key takeaways

Tiangou belongs to science; place it in that map before memorising details.
Learn the definition first, then one example that makes the definition concrete.
Connect Tiangou to a quantity you can measure, compute or draw — that is where exam questions come from.
Reproduce the core statement of Tiangou from memory before moving on to harder problems.

Reference excerpt

The tiangou (Chinese: 天狗; pinyin: tiāngǒu; Wade–Giles: t'ien1-kou3; lit. 'Heavenly Dog') is a legendary creature from China. The tiangou resembles a black dog or meteor, and is thought to eat the Sun or Moon during an eclipse.

Tiangou eating the Sun As a good spirit, it has the appearance of a white-headed fox. It brings peace and tranquility, and gives protection from all sorts of troubles and robbers. It is referred to by astrologers as a constellation guardian of welfare. This asterism consists of seven stars. In ancient Chinese astronomy, Tiangou ('Heavenly Dog') referred to an asterism located in the region of Argo Navis. As a bad spirit, it is a black dog that eats the Moon. According to the legends, as an interpretation of a lunar eclipse, after Houyi shot down the nine Suns in the sky, he was awarded with an immortality-granting pill by the Queen Mother of the West. Before he could eat it, his wife Chang'e consumed the elixir of immortality. Chang'e felt her body getting lighter and flew away. Seeing this, a black dog that Hou Yi was rearing went inside her room and licked the remains of the pill. He then chased after Chang'e, getting bigger and bigger. Chang'e, terrified, hid on the Moon. The black dog then ate the Moon, along with Chang'e. After being informed of this, the Queen Mother of the West captured the dog. Surprised to see that the dog was actually Hou Yi's, she assigned him to guard the gates of heavens and bestowed upon him the title of Tiangou. Tiangou spat the Moon and Chang'e back out, and Chang'e continued living on the Moon.

Battle with Zhang Xian

Zhang Xian (Chinese: 張仙; pinyin: Zhāng Xiān) is the enemy of the tiangou. It is said that he protects his children from the dog god with his bow and arrows. He is often depicted aiming at the sky, waiting for the beast to appear. He is the god of birth and the protector of male children. Many sought for him to give them male offspring and to protect their living sons.

Meaning in Japan

The term tengu and the characters used to write it may be borrowed from the name of tiangou, though this is still to be confirmed. Despite the characters, both creatures are independent mythological creatures with no common ancestor or origin. A tengu is usually depicted as a bird or man with a long nose and other bird-like characteristics, while the tiangou is a dog.

Illustrations

Worked examples

Example 1 — a first encounter with Tiangou

Start with the simplest possible case. Write down what Tiangou claims or describes in one sentence, then invent the smallest concrete situation in which that sentence is true. In science, the smallest case is usually a single object, a single equation or a single measurement. Check that every symbol or term in your sentence has a meaning in that case.

Example 2 — changing one variable

Take the situation from Example 1 and change exactly one quantity: double it, halve it, or set it to zero. Predict what should happen to Tiangou before you calculate. Comparing your prediction with the result is the fastest way to find out whether you understand the idea or only the words.

Example 3 — an exam-style question

Typical questions about Tiangou ask you to (a) state it precisely, (b) apply it to given data, and (c) explain a limitation. Practise writing all three answers in under five minutes; the third part is what separates a full-mark answer from an average one.

Applications of Tiangou

In research: Tiangou appears in science research whenever the underlying quantities have to be modelled precisely. Papers usually cite it as a starting assumption and then explore where it breaks down.
In technology and industry: Engineering practice reuses Tiangou in design rules, simulations and safety margins. Knowing the idea lets you read a specification sheet and understand why the numbers look the way they do.
In the classroom: Tiangou is common in secondary-school and first-year university syllabi. It links to neighbouring topics Black dogs (folklore), Chinese mythology stubs, Dogs in Chinese mythology, so understanding it makes those chapters shorter.
In everyday life: Look for Tiangou outside the textbook — in sport, cooking, traffic, electronics or the sky above you. An example you found yourself is remembered far longer than one you were given.

Affiliate

Preply — study more efficiently by working with a personal tutor. 50% off.

How to study Tiangou in 20 minutes

Read the reference excerpt below once, without taking notes.
Close the page and write down what Tiangou means in your own words.
Compare your version with the excerpt and mark what you missed.
Work through the three examples above with pen and paper.
Explain Tiangou out loud to somebody else — or to Teacher Smith in the lgStudy chat.

Frequently asked questions

What is Tiangou in simple terms?

Why does Tiangou matter?

Because it connects several science ideas at once: it gives you a definition you can apply, a quantity you can calculate, and a way to check whether a result is plausible.

How should I study Tiangou?

Read the excerpt, restate it from memory, then work through the examples and applications listed on this page. The five-step study plan above takes about twenty minutes.

What does this page cover?

It gives you a compact reference excerpt plus original lgStudy explanations, examples, applications and study material on Tiangou.