astronomy

Hiroyasu Koga

Hiroyasu Koga is a astronomy 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 Hiroyasu Koga rather than just read about it. In short: Hiroyasu Koga (Japanese: 古賀浩靖 Koga Hiroyasu, born 15 August 1947) is a former Tatenokai member and kaishakunin responsible for the decapitations of Yukio Mishima and Masakatsu Morita during their seppuku on November 25, 1970. He studied law at Kanagawa University and intended to become a lawyer.

Key takeaways

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

Reference excerpt

Hiroyasu Koga (Japanese: 古賀浩靖 Koga Hiroyasu, born 15 August 1947) is a former Tatenokai member and kaishakunin responsible for the decapitations of Yukio Mishima and Masakatsu Morita during their seppuku on November 25, 1970. He studied law at Kanagawa University and intended to become a lawyer. Koga, known by the nickname Furu-Koga (distinguishing him from another Tatenokai member named Masayoshi Koga who was in turn nicknamed Chibi-Koga, 小賀), was a skilled practitioner of kendo (swordsmanship). It was originally planned that Mishima would be decapitated by Masakatsu Morita, the Tatenokai's student leader; however, Morita was not trained in the sword and failed, at which point Koga stepped in to complete it. Koga then decapitated Morita as part of Morita's own seppuku. Koga and two other participating Tatenokai members (Masayoshi Koga and Masahiro Ogawa) went on trial on March 24, 1971, facing charges of bodily injury, violence, illegal possession of firearms and swords, and assisting a suicide. They were convicted and sentenced to four years' penal servitude, and were released in 1974, a few months early. As of 2005, it was believed that he was a practising Shinto priest at a shrine on Shikoku. However, an alternative belief is that he never became a Shinto priest, instead becoming the head of the Hokkaido branch of Seicho-no-Ie and was renamed Hiroyasu Arechi. It is further posited that he now resides in Kumamoto.

References

Worked examples

Example 1 — a first encounter with Hiroyasu Koga

Start with the simplest possible case. Write down what Hiroyasu Koga claims or describes in one sentence, then invent the smallest concrete situation in which that sentence is true. In astronomy, 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 Hiroyasu Koga 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 Hiroyasu Koga 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 Hiroyasu Koga

In research: Hiroyasu Koga appears in astronomy 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 Hiroyasu Koga 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: Hiroyasu Koga is common in secondary-school and first-year university syllabi. It links to neighbouring topics 1947 births, 20th-century Japanese murderers, Decapitation, so understanding it makes those chapters shorter.
In everyday life: Look for Hiroyasu Koga 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.

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How to study Hiroyasu Koga in 20 minutes

Read the reference excerpt below once, without taking notes.
Close the page and write down what Hiroyasu Koga 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 Hiroyasu Koga out loud to somebody else — or to Teacher Smith in the lgStudy chat.

Frequently asked questions

What is Hiroyasu Koga in simple terms?

Why does Hiroyasu Koga matter?

Because it connects several astronomy 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 Hiroyasu Koga?

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 Hiroyasu Koga.