science

Solunar theory

Solunar theory 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 Solunar theory rather than just read about it. In short: The solunar theory is a hypothesis that fish and other animals move according to the location of the moon in comparison to their bodies. The theory was laid out in 1926 by John Alden Knight, but was said to be used by hunters and fishermen long before the time it was published.

Key takeaways

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

Reference excerpt

The solunar theory is a hypothesis that fish and other animals move according to the location of the moon in comparison to their bodies. The theory was laid out in 1926 by John Alden Knight, but was said to be used by hunters and fishermen long before the time it was published.

History In May 1926, John Alden Knight put together some fishing folklore and other fishing factors such as the sun and the moon, hence the name Solunar (Sol for sun and Lunar for moon) to form a theory on the patterns of animal movement. Knight compiled a list of factors which control or influence the day-to-day behavior of many freshwater and saltwater fish. Each one of the 33 different factors were considered. All but 3 were rejected. The three factors retained were the sun, the moon and the tide. For salt water fishing, tides have long been known as a factor that controls fishes' behavior. As Knight's research progressed, he found that rather than just tides themselves, the relationship of the moon and sun's positions relative to each other may be the determining factor. In addition to the time of moon up (moonrise) - moon down, his research determined that there were intermediate times of the day that occurred in between the two major periods. From that he established that there were major periods (moon up - moon down) and minor periods. Knight published the first Solunar table in 1936.

Tables Solunar tables are tables that fishermen and hunters use to determine the best days of the month and times of the day for catching fish and hunting game. Knowing the time of the tides, sunrise, and sunset help fishermen predict when fish are going to bite. For hunters, the tides are not a factor. Hunters use the alignment of the sun and the moon to determine when game are likely to be moving the most. Other conditions not being unfavourable, fish will feed, land animals will move about, birds will sing and fly from place to place, in theory, all living things will become more active, more alive, during solunar periods than at other times of apparent equal value. "...anglers have found that it is a guide to the best fishing of each day, and the quality of their sport has improved..." Using these tables, a fisherman and a hunter can tell when the moon is directly underfoot or overhead. The strongest activity occurs when there is a full moon or a new moon, and is weakest when there is a quarter moon or a three quarter moon. This is because the combined gravitational force of the moon and the sun is strongest when both are directly above or directly below our heads. People now have access to better lunar data because of improved technology the US Naval Observatory exploits and also because of the availability of, and improvements to, GPS technology. These new technologies have allowed solunar theory to generate hunting and fishing times with much greater precision. Data in tables found on various websites should be reverified periodically with available US Naval Observatory data, as well as compared against other reputable solunar data providers. Inconsistencies abound due to the complex nature of the astrophysics computations and overlooked associated anomalies-checking that are required to produce useful results. Moon transits which do not occur for more than a day, or associated times being off more than a few minutes are indications of a fundamental issue for a given position and should be suspect. All data providers should be verified before assuming data presented is authoritative or accurate.

See also Lunisolar calendar Old Farmer's Almanac Tide table Lunar effect

References

External links Solunar Tables Calendar

Worked examples

Example 1 — a first encounter with Solunar theory

Start with the simplest possible case. Write down what Solunar theory 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 Solunar theory 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 Solunar theory 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 Solunar theory

In research: Solunar theory 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 Solunar theory 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: Solunar theory is common in secondary-school and first-year university syllabi. It links to neighbouring topics Folklore, Hunting, so understanding it makes those chapters shorter.
In everyday life: Look for Solunar theory 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 Solunar theory in 20 minutes

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

Frequently asked questions

What is Solunar theory in simple terms?

Why does Solunar theory 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 Solunar theory?

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 Solunar theory.