astronomy

The Planet That Wasn't

The Planet That Wasn't 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 The Planet That Wasn't rather than just read about it. In short: The Planet That Wasn't is a collection of seventeen scientific essays by American writer and scientist Isaac Asimov. It was the twelfth of a series of books collecting essays from The Magazine of Fantasy and Science Fiction.

Key takeaways

The Planet That Wasn't belongs to astronomy; place it in that map before memorising details.
Learn the definition first, then one example that makes the definition concrete.
Connect The Planet That Wasn't to a quantity you can measure, compute or draw — that is where exam questions come from.
Reproduce the core statement of The Planet That Wasn't from memory before moving on to harder problems.

Reference excerpt

The Planet That Wasn't is a collection of seventeen scientific essays by American writer and scientist Isaac Asimov. It was the twelfth of a series of books collecting essays from The Magazine of Fantasy and Science Fiction. These essays were first published between December 1974 and April 1976. It was first published by Doubleday & Company in 1976.

Contents "Star In The East" (F&SF, December 1974) "Thinking About Thinking" (January 1975) "The Rocketing Dutchmen" (February 1975) "The Bridge of the Gods" (March 1975) "The Judo Argument" (April 1975) "The Planet That Wasn't" (May 1975) "The Olympian Snows" (June 1975) "Titanic Surprise" (July 1975) "The Wicked Witch is Dead" (August 1975) "The Wrong Turning" (September 1975) "The Third Liquid" (October 1975) "Best Foot Backward" (November 1975) "The Smell of Electricity" (December 1975) "Silent Victory" (January 1976) "Change of Air" (February 1976) "The Nightfall Effect" (March 1976) "All Gall" (April 1976)

References

External links Asimovonline.com The Planet That Wasn't at Goodreads.com

Worked examples

Example 1 — a first encounter with The Planet That Wasn't

Start with the simplest possible case. Write down what The Planet That Wasn't 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 The Planet That Wasn't 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 The Planet That Wasn't 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 The Planet That Wasn't

In research: The Planet That Wasn't 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 The Planet That Wasn't 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: The Planet That Wasn't is common in secondary-school and first-year university syllabi. It links to neighbouring topics 1976 books, Doubleday (publisher) books, Essay collections by Isaac Asimov, so understanding it makes those chapters shorter.
In everyday life: Look for The Planet That Wasn't 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 The Planet That Wasn't in 20 minutes

Read the reference excerpt below once, without taking notes.
Close the page and write down what The Planet That Wasn't 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 The Planet That Wasn't out loud to somebody else — or to Teacher Smith in the lgStudy chat.

Frequently asked questions

What is The Planet That Wasn't in simple terms?

Why does The Planet That Wasn't 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 The Planet That Wasn't?

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 The Planet That Wasn't.