science

Wolf 489

Wolf 489 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 Wolf 489 rather than just read about it. In short: Wolf 489 (WD 1334+039, LHS 46, G 062-053, Gliese 518) is a nearby degenerate star (white dwarf) of spectral class DZ10.0), the single known component of the system, located in the constellation Virgo. Distance Wolf 489, probably, is the 12th closest white dwarf, or, possibly, 9th–14th (see Gliese 293, GJ 1087, Gliese 915, GJ 1276 and Gliese 318).

Key takeaways

Wolf 489 belongs to science; place it in that map before memorising details.
Learn the definition first, then one example that makes the definition concrete.
Connect Wolf 489 to a quantity you can measure, compute or draw — that is where exam questions come from.
Reproduce the core statement of Wolf 489 from memory before moving on to harder problems.

Reference excerpt

Distance Wolf 489, probably, is the 12th closest white dwarf, or, possibly, 9th–14th (see Gliese 293, GJ 1087, Gliese 915, GJ 1276 and Gliese 318). Its trigonometric parallax from YPC (Yale Parallax Catalog) is 121.4 ± 3.4 mas, corresponding to a distance 8.24 ± 0.23 pc, or 26.87 ± 0.75 ly.

Physical parameters Wolf 489's mass is 0.55 ± 0.03 Solar masses, its surface gravity is 107.95 ± 0.02 (8.91 · 107) cm·s−2, or approximately 91 000 of Earth's, corresponding to a radius 9089 km, or 143% of Earth's. Wolf 489's temperature is 5030 ± 120 K (comparable with that of early K-type main sequence stars); its cooling age, i. e. age as degenerate star (not including lifetime as main sequence star and as giant star) is 5.19 Gyr. Wolf 489 should appear white with a slight shade of yellow, nearly the same color as a K-type main sequence star.

Notes

See also List of star systems within 25–30 light-years

References

Worked examples

Example 1 — a first encounter with Wolf 489

Start with the simplest possible case. Write down what Wolf 489 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 Wolf 489 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 Wolf 489 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 Wolf 489

In research: Wolf 489 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 Wolf 489 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: Wolf 489 is common in secondary-school and first-year university syllabi. It links to neighbouring topics Gliese and GJ objects, Virgo (constellation), White dwarfs, so understanding it makes those chapters shorter.
In everyday life: Look for Wolf 489 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 Wolf 489 in 20 minutes

Read the reference excerpt below once, without taking notes.
Close the page and write down what Wolf 489 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 Wolf 489 out loud to somebody else — or to Teacher Smith in the lgStudy chat.

Frequently asked questions

What is Wolf 489 in simple terms?

Wolf 489 (WD 1334+039, LHS 46, G 062-053, Gliese 518) is a nearby degenerate star (white dwarf) of spectral class DZ10.0), the single known component of the system, located in the constellation Virgo. Distance Wolf 489, probably, is the 12th closest white dwarf, or, possibly, 9th–14th (see Gliese 2…

Why does Wolf 489 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 Wolf 489?

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 Wolf 489.