astronomy

NGC 4242

NGC 4242 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 4242 rather than just read about it. In short: NGC 4242 is a spiral galaxy in the northern constellation of Canes Venatici. The galaxy is about 18 million light years (5.5 megaparsecs) away.

Key takeaways

NGC 4242 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 4242 to a quantity you can measure, compute or draw — that is where exam questions come from.
Reproduce the core statement of NGC 4242 from memory before moving on to harder problems.

Reference excerpt

NGC 4242 is a spiral galaxy in the northern constellation of Canes Venatici. The galaxy is about 18 million light years (5.5 megaparsecs) away. It was discovered on 10 April 1788 by William Herschel, and it was described as "very faint, considerably large, irregular, round, very gradually brighter in the middle, resolvable" by John Louis Emil Dreyer, the compiler of the New General Catalogue. NGC 4242's galaxy morphological type is SABdm. This means that it is an intermediate spiral galaxy, with loosely wound spiral arms and is generally irregular in appearance. It was photographed by the Hubble Space Telescope in 2017. The image shows an asymmetric center and a small galactic bar. NGC 4242 has a relatively low surface brightness and rate of star formation. NGC 4242 may be a satellite galaxy of Messier 106 and is a member of the Canes II Group. SN 2002bu was detected in NGC 4242, brightening to its peak magnitude of 15.5 in 2002. It was originally classified as a type II supernova. In 2011, it was thought to be a supernova impostor like SN 2008S, and in 2021 researchers reclassified it as a gap transient.

Gallery

References

External links Media related to NGC 4242 at Wikimedia Commons

Illustrations

Worked examples

Example 1 — a first encounter with NGC 4242

Start with the simplest possible case. Write down what NGC 4242 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 4242 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 4242 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 4242

In research: NGC 4242 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 4242 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 4242 is common in secondary-school and first-year university syllabi. It links to neighbouring topics Canes II Group, Canes Venatici, Intermediate spiral galaxies, so understanding it makes those chapters shorter.
In everyday life: Look for NGC 4242 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 4242 in 20 minutes

Read the reference excerpt below once, without taking notes.
Close the page and write down what NGC 4242 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 4242 out loud to somebody else — or to Teacher Smith in the lgStudy chat.

Frequently asked questions

What is NGC 4242 in simple terms?

NGC 4242 is a spiral galaxy in the northern constellation of Canes Venatici. The galaxy is about 18 million light years (5.5 megaparsecs) away.

Why does NGC 4242 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 4242?

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 4242.