science

IC 4665

IC 4665 is a science 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 IC 4665 rather than just read about it. In short: IC 4665 (Collinder 349 / Melotte 179), also known as the Summer Beehive Cluster or Poseidon's Trident , is an open cluster of stars in the constellation Ophiuchus, about 1° to the northeast of the star Beta Ophiuchi. It was discovered by Swiss astronomer Philippe Loys de Chéseaux in 1745.

Key takeaways

IC 4665 belongs to science; place it in that map before memorising details.
Learn the definition first, then one example that makes the definition concrete.
Connect IC 4665 to a quantity you can measure, compute or draw — that is where exam questions come from.
Reproduce the core statement of IC 4665 from memory before moving on to harder problems.

Reference excerpt

IC 4665 (Collinder 349 / Melotte 179), also known as the Summer Beehive Cluster or Poseidon's Trident , is an open cluster of stars in the constellation Ophiuchus, about 1° to the northeast of the star Beta Ophiuchi. It was discovered by Swiss astronomer Philippe Loys de Chéseaux in 1745. The cluster lies about 1,100 light years away from Earth. It is easily visible in the smallest of telescopes and also with binoculars. From a sufficiently dark place it is also visible to the naked eye. It is one of the brightest clusters not to be cataloged by Charles Messier or William Herschel, probably because it is so loose and coarse. Age estimates for this cluster have ranged from 20 up to as high as 100 million years. Comparison of the stellar lithium depletion with other clusters suggests it began to develop about 55 million years ago. The upper main sequence turnoff age is 42±12 Myr. 819 candidate cluster members have been identified. Two chemically peculiar stars were found to be members in 1977. It has an estimated mass of about 130 suns. There is evidence that IC 4665 is undergoing a collision with the older cluster Collinder 350, located about 4° away. Currently they are separated by a distance of 118.2 ly (36.25 pc), after having formed at least 1,600 ly (500 pc) apart. It is unclear whether the two clusters will merge as a result of the collision.

References

External links Media related to IC 4665 at Wikimedia Commons IC 4665 @ SEDS IC objects pages IC 4665 www.univie.ac.at

IC 4665 on WikiSky: DSS2, SDSS, GALEX, IRAS, Hydrogen α, X-Ray, Astrophoto, Sky Map, Articles and images X-Ray Activity in the Open Cluster IC 4665 National Aeronautics and Space Administration

Illustrations

Worked examples

Example 1 — a first encounter with IC 4665

Start with the simplest possible case. Write down what IC 4665 claims or describes in one sentence, then invent the smallest concrete situation in which that sentence is true. In science, 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 IC 4665 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 IC 4665 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 IC 4665

In research: IC 4665 appears in science 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 IC 4665 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: IC 4665 is common in secondary-school and first-year university syllabi. It links to neighbouring topics IC objects, Open clusters, Ophiuchus, so understanding it makes those chapters shorter.
In everyday life: Look for IC 4665 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 IC 4665 in 20 minutes

Read the reference excerpt below once, without taking notes.
Close the page and write down what IC 4665 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 IC 4665 out loud to somebody else — or to Teacher Smith in the lgStudy chat.

Frequently asked questions

What is IC 4665 in simple terms?

Why does IC 4665 matter?

Because it connects several science 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 IC 4665?

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 IC 4665.