astronomy

NGC 846

NGC 846 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 846 rather than just read about it. In short: NGC 846 (also known as NGC 847) is a barred spiral galaxy located around 235 million light-years away in the constellation Andromeda. NGC 846 was discovered on November 22nd, 1876 by the French astronomer Édouard Stephan, and it has a diameter of around 162,000 light-years.

Key takeaways

NGC 846 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 846 to a quantity you can measure, compute or draw — that is where exam questions come from.
Reproduce the core statement of NGC 846 from memory before moving on to harder problems.

Reference excerpt

NGC 846 (also known as NGC 847) is a barred spiral galaxy located around 235 million light-years away in the constellation Andromeda. NGC 846 was discovered on November 22nd, 1876 by the French astronomer Édouard Stephan, and it has a diameter of around 162,000 light-years. NGC 846 is not known to have much star-formation, and it is not known to have an active galactic nucleus.

Supernovae Two supernovae have been observed in NGC 846:

SN 2003ja (Type II, mag. 17.1) was discovered by the Lick Observatory Supernova Search (LOSS) on 22 October 2003. SN 2009fu (Type Ia, mag. 15.7) was discovered by Kōichi Itagaki on 1 June 2009.

Illustrations

Worked examples

Example 1 — a first encounter with NGC 846

Start with the simplest possible case. Write down what NGC 846 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 846 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 846 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 846

In research: NGC 846 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 846 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 846 is common in secondary-school and first-year university syllabi. It links to neighbouring topics Andromeda (constellation), Astronomical objects discovered in 1876, Barred spiral galaxies, so understanding it makes those chapters shorter.
In everyday life: Look for NGC 846 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 846 in 20 minutes

Read the reference excerpt below once, without taking notes.
Close the page and write down what NGC 846 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 846 out loud to somebody else — or to Teacher Smith in the lgStudy chat.

Frequently asked questions

What is NGC 846 in simple terms?

Why does NGC 846 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 846?

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 846.