astronomy

NGC 4651

NGC 4651 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 4651 rather than just read about it. In short: NGC 4651 is a spiral galaxy located in the constellation of Coma Berenices that can be seen with amateur telescopes, at a distance not well determined that ranges from 35 million light years to 72 million light years. It was discovered by German-British astronomer William Herschel on 30 December 1783.

Key takeaways

NGC 4651 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 4651 to a quantity you can measure, compute or draw — that is where exam questions come from.
Reproduce the core statement of NGC 4651 from memory before moving on to harder problems.

Reference excerpt

NGC 4651 is a spiral galaxy located in the constellation of Coma Berenices that can be seen with amateur telescopes, at a distance not well determined that ranges from 35 million light years to 72 million light years. It was discovered by German-British astronomer William Herschel on 30 December 1783.

Features This member of the Virgo Cluster, located on its outskirts, is known as the Umbrella Galaxy due to the umbrella-shaped structure that extends from its disk to the east and that is composed of stellar streams, being the remnants of a much smaller galaxy that has been torn apart by NGC 4651's tidal forces, something that explains why NGC 4651 has been included on Halton Arp's Atlas of Peculiar Galaxies as Arp 189 -galaxy with filaments-. Studies using radiotelescopes of the distribution of its neutral hydrogen show distortions on NGC 4651's outer regions and a gas clump associated with a dwarf galaxy that may have been born in the event that produced the mentioned stellar streams. Unlike most spiral galaxies of the Virgo Cluster, NGC 4651 is rich in neutral hydrogen, also extending beyond the optical disk, and its star formation is typical for a galaxy of its type.

Supernovae Two supernovae have been observed in NGC 4651:

SN 1987K (Type II, mag. 15) was discovered by Carlton Pennypacker on 28 July 1987. SN 2006my (Type II, mag. 15.3) was discovered by Kōichi Itagaki on 8 November 2006.

References

External links Media related to NGC 4651 at Wikimedia Commons

Illustrations

Worked examples

Example 1 — a first encounter with NGC 4651

Start with the simplest possible case. Write down what NGC 4651 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 4651 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 4651 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 4651

In research: NGC 4651 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 4651 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 4651 is common in secondary-school and first-year university syllabi. It links to neighbouring topics Arp objects, Astronomical objects discovered in 1783, Coma Berenices, so understanding it makes those chapters shorter.
In everyday life: Look for NGC 4651 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 4651 in 20 minutes

Read the reference excerpt below once, without taking notes.
Close the page and write down what NGC 4651 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 4651 out loud to somebody else — or to Teacher Smith in the lgStudy chat.

Frequently asked questions

What is NGC 4651 in simple terms?

Why does NGC 4651 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 4651?

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 4651.