astronomy

HD 88231

HD 88231 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 HD 88231 rather than just read about it. In short: HD 88231, also known as HR 3993, is a solitary orange-hued star located in the northern constellation Leo Minor. It has an apparent magnitude of 5.84, making it faintly visible to the naked eye under ideal conditions.

Key takeaways

HD 88231 belongs to astronomy; place it in that map before memorising details.
Learn the definition first, then one example that makes the definition concrete.
Connect HD 88231 to a quantity you can measure, compute or draw — that is where exam questions come from.
Reproduce the core statement of HD 88231 from memory before moving on to harder problems.

Reference excerpt

HD 88231, also known as HR 3993, is a solitary orange-hued star located in the northern constellation Leo Minor. It has an apparent magnitude of 5.84, making it faintly visible to the naked eye under ideal conditions. Gaia DR3 parallax measurements imply a distance of about 569 light-years, and the object is currently receding with a heliocentric radial velocity of 7.38 km/s. At its current distance, HD 88231's brightness is diminished by 0.17 magnitudes due to interstellar extinction and it has an absolute magnitude of −0.59. The object has a stellar classification of K3 III, indicating that it is an evolved red giant star. It has a comparable mass to the Sun but it has expanded to 24.9 times the radius of the Sun. It radiates 228 times the luminosity of the Sun from its enlarged photosphere at an effective temperature of 4,487 K. HD 88231 is slightly metal enriched with an iron abundance 112% that of the Sun ([Fe/H] = +0.05). HD 88231 was suspected to be variable in the K-band based on Two-Micron Sky Survey observations in 1969. A 1994 paper found that it ranges from 5.79 to 5.88 in the visual band. As of 2004 however, the variability has not been confirmed.

References

Illustrations

Worked examples

Example 1 — a first encounter with HD 88231

Start with the simplest possible case. Write down what HD 88231 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 HD 88231 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 HD 88231 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 HD 88231

In research: HD 88231 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 HD 88231 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: HD 88231 is common in secondary-school and first-year university syllabi. It links to neighbouring topics Bright Star Catalogue objects, Durchmusterung objects, Henry Draper Catalogue objects, so understanding it makes those chapters shorter.
In everyday life: Look for HD 88231 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 HD 88231 in 20 minutes

Read the reference excerpt below once, without taking notes.
Close the page and write down what HD 88231 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 HD 88231 out loud to somebody else — or to Teacher Smith in the lgStudy chat.

Frequently asked questions

What is HD 88231 in simple terms?

Why does HD 88231 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 HD 88231?

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 HD 88231.