astronomy

WASP-49

WASP-49 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 WASP-49 rather than just read about it. In short: WASP-49 is a binary star system about 636 light-years (195 parsecs) away in the constellation Lepus. The two stars are separated by 443 AU.

Key takeaways

WASP-49 belongs to astronomy; place it in that map before memorising details.
Learn the definition first, then one example that makes the definition concrete.
Connect WASP-49 to a quantity you can measure, compute or draw — that is where exam questions come from.
Reproduce the core statement of WASP-49 from memory before moving on to harder problems.

Reference excerpt

WASP-49 is a binary star system about 636 light-years (195 parsecs) away in the constellation Lepus. The two stars are separated by 443 AU. The primary is a G-type main-sequence star, with a surface temperature of 5,600 K (5,330 °C; 9,620 °F). WASP-49 is depleted of heavy elements relative to the Sun. It has a metallicity Fe/H index of –0.23, meaning it has 59% the iron level of the Sun.

Planetary system In 2012, one exoplanet, designated WASP-49b, was discovered around the primary star by a team led by Monika Lendl. This is a hot Jupiter with an equilibrium temperature of 1369±39 K. In 2017, WASP-49b was found to have an extensive sodium envelope. A study in 2019 using data from the Hubble Space Telescope in near-UV found clear absorption features caused by metals, including magnesium and iron. The gaseous magnesium and iron is not gravitationally bound to the planet, but could be magnetically confined to it. The sodium layer around WASP-49b could be due to a tidally-heated Io-like exomoon. In October 2024, a 5-year study was published indicating that the sodium envelope most likely comes from a distinct body orbiting WASP-49b rather than the star or the planet, although the exact dynamics of the envelope remains to be settled.

References

Further reading Unni, Athira; Oza, Apurva V.; et al. (June 2025). "Doppler shifted transient sodium detection by KECK/HIRES". Monthly Notices of the Royal Astronomical Society: Letters. 540 (1): L48–L53. arXiv:2504.03974. Bibcode:2025MNRAS.540L..48U. doi:10.1093/mnrasl/slaf031.

Worked examples

Example 1 — a first encounter with WASP-49

Start with the simplest possible case. Write down what WASP-49 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 WASP-49 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 WASP-49 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 WASP-49

In research: WASP-49 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 WASP-49 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: WASP-49 is common in secondary-school and first-year university syllabi. It links to neighbouring topics Binary stars, Exomoons, G-type main-sequence stars, so understanding it makes those chapters shorter.
In everyday life: Look for WASP-49 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 “WASP-49” →

Affiliate

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

How to study WASP-49 in 20 minutes

Read the reference excerpt below once, without taking notes.
Close the page and write down what WASP-49 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 WASP-49 out loud to somebody else — or to Teacher Smith in the lgStudy chat.

Frequently asked questions

What is WASP-49 in simple terms?

WASP-49 is a binary star system about 636 light-years (195 parsecs) away in the constellation Lepus. The two stars are separated by 443 AU.

Why does WASP-49 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 WASP-49?

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 WASP-49.