science

WD 2317+1830

WD 2317+1830 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 WD 2317+1830 rather than just read about it. In short: WD 2317+1830 (SDSS J231726.72+183049.6) is one of the first white dwarfs with lithium detected in its atmosphere. The white dwarf is surrounded by a debris disk and is actively accreting material.

Key takeaways

WD 2317+1830 belongs to science; place it in that map before memorising details.
Learn the definition first, then one example that makes the definition concrete.
Connect WD 2317+1830 to a quantity you can measure, compute or draw — that is where exam questions come from.
Reproduce the core statement of WD 2317+1830 from memory before moving on to harder problems.

Reference excerpt

WD 2317+1830 (SDSS J231726.72+183049.6) is one of the first white dwarfs with lithium detected in its atmosphere. The white dwarf is surrounded by a debris disk and is actively accreting material. Researchers suggest that the presence of alkali metals indicates the accretion of crust material. Another work however cautions to use alkali metals as a single indicator of crust material. They suggest that such objects could be polluted by mantle material instead. An analysis in 2024 finds that the abundance of lithium is in agreement with Big Bang nucleosynthesis (BBN) and galactic nucleosynthesis. WD 2317+1830 likely was a star with sub-solar metallicity, which is evident from its old age, as well as from its thick disk or halo kinematics. This low metallicity means that the planetesimals that formed around this old white dwarf had a composition more similar to BBN abundances. The lithium-enhancement is not in agreement with the accretion of terrestrial continental crust material. The accretion of an exotic exoplanet is not ruled out, but the accretion of a primitive planetesimal is more likely. The accretion of an exomoon as a lithium source is excluded. WD 2317+1830 was first discovered in 2021 from Gaia and SDSS data as a candidate white dwarf. A first spectral analysis was published in 2020, identifying it as a DZ white dwarf. In 2021 observations with the Gran Telescopio Canarias were published. The white dwarf is massive and has a mass of 1.00 ± 0.02 M☉. The cooling age was determined to be 9.5±0.2 Gyrs and the total age is 9.7±0.2 Gyrs. A more recent work found a higher temperature and younger cooling age of about 6.4 Gyrs. The researchers detected sodium, lithium and weak calcium absorption. The researchers also detected infrared excess, indicative of a debris disk, around this white dwarf. The disk is inclined by 70°, has an inner disk temperature of 1,500 K and an outer disk temperature of 500 K. In the past WD 2317+1830 had a mass of 4.8 ± 0.2 M☉ and was likely a B-type star.

See also List of exoplanets and planetary debris around white dwarfs WD J2356−209 is another cool white dwarf with sodium detected LSPM J0207+3331 is another old white dwarf with a disk detected

References

Illustrations

Worked examples

Example 1 — a first encounter with WD 2317+1830

Start with the simplest possible case. Write down what WD 2317+1830 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 WD 2317+1830 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 WD 2317+1830 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 WD 2317+1830

In research: WD 2317+1830 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 WD 2317+1830 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: WD 2317+1830 is common in secondary-school and first-year university syllabi. It links to neighbouring topics Circumstellar disks, Pegasus (constellation), White dwarfs, so understanding it makes those chapters shorter.
In everyday life: Look for WD 2317+1830 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.

Ask Teacher Smith questions about this articleOpens your AI tutor with a question about “WD 2317+1830” →

Affiliate

Preply — study more efficiently by working with a personal tutor. 50% off.

How to study WD 2317+1830 in 20 minutes

Read the reference excerpt below once, without taking notes.
Close the page and write down what WD 2317+1830 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 WD 2317+1830 out loud to somebody else — or to Teacher Smith in the lgStudy chat.

Frequently asked questions

What is WD 2317+1830 in simple terms?

WD 2317+1830 (SDSS J231726.72+183049.6) is one of the first white dwarfs with lithium detected in its atmosphere. The white dwarf is surrounded by a debris disk and is actively accreting material.

Why does WD 2317+1830 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 WD 2317+1830?

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 WD 2317+1830.