astronomy

NGC 4565

NGC 4565 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 4565 rather than just read about it. In short: NGC 4565 (also known as the Needle Galaxy, Flying Saucer Galaxy, Berenice's Hair Clip or Caldwell 38) is an edge-on spiral galaxy about 30 to 50 million light-years away in the constellation Coma Berenices. It lies close to the North Galactic Pole and has a visual magnitude of approximately 10.

Key takeaways

NGC 4565 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 4565 to a quantity you can measure, compute or draw — that is where exam questions come from.
Reproduce the core statement of NGC 4565 from memory before moving on to harder problems.

Reference excerpt

NGC 4565 (also known as the Needle Galaxy, Flying Saucer Galaxy, Berenice's Hair Clip or Caldwell 38) is an edge-on spiral galaxy about 30 to 50 million light-years away in the constellation Coma Berenices. It lies close to the North Galactic Pole and has a visual magnitude of approximately 10. It is a prominent example of an edge-on spiral galaxy, known as the Needle Galaxy for its narrow profile. It was discovered by William Herschel on 6 April 1785.

Characteristics NGC 4565 is a giant spiral galaxy more luminous than the Andromeda Galaxy. Much speculation exists concerning the nature of the central bulge. In the absence of clear-cut dynamical data on the motions of stars in the bulge, the photometric data alone cannot adjudge among various options. However, its exponential shape suggested that it is a barred spiral galaxy. Studies with the help of the Spitzer Space Telescope not only confirmed the presence of a central bar but also showed a pseudobulge within it, as well as an inner ring.

This edge-on galaxy exhibits a slightly warped and extended disk under deep optical surveys, likely due to ongoing interaction with neighboring satellite galaxies or other galaxies in the Coma I group. GALEX images show the slight warp at the edge of the disc more clearly than other surveys. Using the LOw-Frequency ARray (LOFAR), astronomers of the University of Hamburg discovered a diffuse radio halo around NGC 4565. During the observations, a warp was detected in the radio continuum of NGC 4565 that is reminiscent of a neutral hydrogen line (HI) warp and identifying a slight flaring of the galaxy's radio halo. It is assumed that this flaring is caused by the warp, as the vertical intensity profiles are asymmetric in agreement with the warp. According to the study, a minimum age for the warp was estimated at approximately 130 million years. This is the spectral age of the galaxy's cosmic ray electrons, during which they are transported into the warp. This indicates that NGC 4565 may be in the aftermath of a period with more intense star formation, likely caused by interaction with one or both satellites. An H I bridge extending from NGC 4565 to IC 3571 also implies that interaction has happened recently in cosmic terms

Galaxy Groups NGC 4565, along with NGC 4562, IC 3543, and IC 3546, are listed together as Holm 426 in Erik Holmberg's A Study of Double and Multiple Galaxies Together with Inquiries into some General Metagalactic Problems, published in 1937. NGC 4565 has at least two satellite galaxies, NGC 4562 and IC 3571, one of which is interacting with it. It has a population of roughly 240 globular clusters, more than the Milky Way. NGC 4565 is one of the brightest galaxies of the Coma I Group.

Gallery

References

External links Media related to NGC 4565 at Wikimedia Commons

NGC 4565 on WikiSky: DSS2, SDSS, GALEX, IRAS, Hydrogen α, X-Ray, Astrophoto, Sky Map, Articles and images National Optical Astronomical Observatory Archived 2009-05-22 at the Wayback Machine – NGC 4565 APOD (2024-06-06) - NGC 4565: Galaxy on Edge APOD (2010-03-04) – NGC 4565: Galaxy on Edge APOD (2009-04-28) – NGC 4565 SEDS – NGC 4565

Illustrations

Worked examples

Example 1 — a first encounter with NGC 4565

Start with the simplest possible case. Write down what NGC 4565 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 4565 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 4565 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 4565

In research: NGC 4565 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 4565 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 4565 is common in secondary-school and first-year university syllabi. It links to neighbouring topics Astronomical objects discovered in 1785, Caldwell objects, Coma Berenices, so understanding it makes those chapters shorter.
In everyday life: Look for NGC 4565 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 4565 in 20 minutes

Read the reference excerpt below once, without taking notes.
Close the page and write down what NGC 4565 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 4565 out loud to somebody else — or to Teacher Smith in the lgStudy chat.

Frequently asked questions

What is NGC 4565 in simple terms?

Why does NGC 4565 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 4565?

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 4565.