astronomy

NGC 2423-3

NGC 2423-3 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 NGC 2423-3 rather than just read about it. In short: NGC 2423-3 is a red giant star approximately 3,040 light-years away in the constellation of Puppis. The star is part of the NGC 2423 open cluster (hence the name NGC 2423-3).

Key takeaways

NGC 2423-3 belongs to astronomy; place it in that map before memorising details.
Learn the definition first, then one example that makes the definition concrete.
Connect NGC 2423-3 to a quantity you can measure, compute or draw — that is where exam questions come from.
Reproduce the core statement of NGC 2423-3 from memory before moving on to harder problems.

Reference excerpt

NGC 2423-3 is a red giant star approximately 3,040 light-years away in the constellation of Puppis. The star is part of the NGC 2423 open cluster (hence the name NGC 2423-3). The star has an apparent magnitude of 10 and an absolute magnitude of zero, with a mass of 2.4 times the Sun. In 2007, it was proposed that an exoplanet orbits the star, but this is now doubtful.

Planetary system NGC 2423-3 b is an exoplanet 10.6 times more massive than Jupiter. Only the minimum mass is known since the orbital inclination is not known, so it is likely to be a brown dwarf instead. The planet orbits at 2.1 AU, taking 1.956 years to orbit eccentrically around the star. Its eccentricity is about the same as Mercury, but less than Pluto. The planet has a semi-amplitude of 71.5 m/s. This planet was discovered by Christophe Lovis and Michel Mayor in July 2007 by the radial velocity method. Lovis had also found three Neptune-mass planets orbiting HD 69830 in May 2006, also in Puppis. However, a 2018 study with the same C. Lovis as an author found evidence that the radial velocity signal corresponding to the proposed planetary companion could be caused by stellar activity or stellar pulsations, and so the planet may not exist. Another study by the same team in 2023 confirms evidence for a stellar origin of the signal.

Worked examples

Example 1 — a first encounter with NGC 2423-3

Start with the simplest possible case. Write down what NGC 2423-3 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 NGC 2423-3 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 NGC 2423-3 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 NGC 2423-3

In research: NGC 2423-3 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 NGC 2423-3 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: NGC 2423-3 is common in secondary-school and first-year university syllabi. It links to neighbouring topics Durchmusterung objects, Hypothetical planetary systems, M-type giants, so understanding it makes those chapters shorter.
In everyday life: Look for NGC 2423-3 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.

Affiliate

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

How to study NGC 2423-3 in 20 minutes

Read the reference excerpt below once, without taking notes.
Close the page and write down what NGC 2423-3 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 NGC 2423-3 out loud to somebody else — or to Teacher Smith in the lgStudy chat.

Frequently asked questions

What is NGC 2423-3 in simple terms?

NGC 2423-3 is a red giant star approximately 3,040 light-years away in the constellation of Puppis. The star is part of the NGC 2423 open cluster (hence the name NGC 2423-3).

Why does NGC 2423-3 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 NGC 2423-3?

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 NGC 2423-3.