astronomy

NGC 2857

NGC 2857 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 2857 rather than just read about it. In short: NGC 2857 (also known as Arp 1 and PGC 26666) is a spiral galaxy in the constellation Ursa Major. It was discovered on January 9, 1856, by R.

Key takeaways

NGC 2857 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 2857 to a quantity you can measure, compute or draw — that is where exam questions come from.
Reproduce the core statement of NGC 2857 from memory before moving on to harder problems.

Reference excerpt

NGC 2857 (also known as Arp 1 and PGC 26666) is a spiral galaxy in the constellation Ursa Major. It was discovered on January 9, 1856, by R. J. Mitchell. NGC 2857 is the first object in Halton Arp's Atlas of Peculiar Galaxies, and one of six Arp objects in the 'Low Surface Brightness Galaxies' section. The other five low surface brightness galaxies are Arp 2 (UGC 10310), Arp 3, Arp 4, Arp 5 (NGC 3664), and Arp 6 (NGC 2537).

Supernova One supernova has been observed in NGC 2857:

SN 2012fg (Type II-P, mag. 14.5) was discovered by the MASTER-Kislovodsk auto-detection system on October 7, 2012. Its absolute magnitude was calculated to be -19.8. The spectrum of SN 2012fg was recorded and analyzed by multiple teams of scientists as it changed rapidly in the days following its detection.

References

External links Media related to NGC 2857 at Wikimedia Commons Full Arp Atlas Halton Arp's image of Arp 1 Constellation Locator SIMBAD Astronomical Database NASA/IPAC Extragalactic Database SN 2012fg detection announcement

Illustrations

Worked examples

Example 1 — a first encounter with NGC 2857

Start with the simplest possible case. Write down what NGC 2857 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 2857 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 2857 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 2857

In research: NGC 2857 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 2857 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 2857 is common in secondary-school and first-year university syllabi. It links to neighbouring topics Arp objects, Low surface brightness galaxies, NGC objects, so understanding it makes those chapters shorter.
In everyday life: Look for NGC 2857 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.

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How to study NGC 2857 in 20 minutes

Read the reference excerpt below once, without taking notes.
Close the page and write down what NGC 2857 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 2857 out loud to somebody else — or to Teacher Smith in the lgStudy chat.

Frequently asked questions

What is NGC 2857 in simple terms?

NGC 2857 (also known as Arp 1 and PGC 26666) is a spiral galaxy in the constellation Ursa Major. It was discovered on January 9, 1856, by R.

Why does NGC 2857 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 2857?

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 2857.