astronomy

NGC 5907

NGC 5907 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 5907 rather than just read about it. In short: NGC 5907 (also known as NGC 5906, Knife Edge Galaxy, or Splinter Galaxy) is a spiral galaxy located approximately 46.5 million light years from Earth. German-British astronomer William Herschel discovered the galaxy on 5 May 1788.

Key takeaways

NGC 5907 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 5907 to a quantity you can measure, compute or draw — that is where exam questions come from.
Reproduce the core statement of NGC 5907 from memory before moving on to harder problems.

Reference excerpt

NGC 5907 (also known as NGC 5906, Knife Edge Galaxy, or Splinter Galaxy) is a spiral galaxy located approximately 46.5 million light years from Earth. German-British astronomer William Herschel discovered the galaxy on 5 May 1788. Its most notable features are its large stellar stream and ultraluminous X-ray source.

Characteristics NGC 5907 has an anomalously low metallicity and few detectable giant stars, being apparently composed almost entirely of dwarf stars. It is a member of the NGC 5866 Group. NGC 5907 has long been considered a prototypical example of a warped spiral in relative isolation. In 1998, a faint ring structure, likely caused by a disrupted dwarf spheroidal galaxy, was first observed around the galaxy. This challenged the assumption of isolation and suggests the gravitational perturbations induced by the stream progenitor may be the cause for the warp. Then, in 2008, an international team of astronomers announced the presence of an extended double loop tidal stream coiling around the galaxy. The existence of part of these tidal streams has been recently challenged by some deeper surveys, which show only a single knee-shaped stream as opposed to the full double loop structure. This shorter stream has a length of 45′ in the sky (or a physical size of 220 kpc) and has a surface brightness ranging from 27.6 mag/arcsec2 at its brightest to 28.8 at its faintest. An ultraluminous X-ray source, NGC 5907 ULX-1, is located in the galaxy. This source is also called an ultraluminous X-ray pulsar (ULXP) because it exhibits a rapid pulsation effect. This pulsation has a period of 5.7 days and is caused by a rotating neutron star orbiting a high mass companion. The neutron star itself has a spin period of 1.13 seconds and seems to be accelerating; its period ten years prior was 1.43 seconds. It is one of the brightest such source yet discovered with a luminosity over 1041 erg/s (7 orders of magnitude more luminous than the Sun). Notably, its peak luminosity is over 1000 times greater than the Eddington luminosity for a neutron star. NGC 5907 and the galaxy KUG 1513+566 are listed together as Holm 704 in Erik Holmberg's A Study of Double and Multiple Galaxies Together with Inquiries into some General Metagalactic Problems, published in 1937.

NGC 5907 group NGC 5907 is part of a group of galaxies that bears its name. The NGC 5907 group (also known as LGG 396) has at least four members, including Messier 102, NGC 5879, and UGC 9776.

Supernovae

Two supernovae have been observed in NGC 5907:

SN 1940A (Type II-L, mag 14.3) was discovered by Josef J. Johnson on 16 February 1940. SN 2026kid (Type II, mag. 16.62) was discovered by Yasuo Sano on 22 April 2026.

Location

The edge-on galaxy is seen in the constellation Draco, near the star iota Draconis. It is seen in the sky near to the much more distant galaxy NGC 5965.

NGC Identification NGC 5907 is also known as NGC 5906. This second NGC number refers to a fainter part of the galaxy lying west of the dust lane that was recorded by astronomer and physicist George Johnstone Stoney on April 13, 1850.

Gallery

References

External links

NGC 5907 on WikiSky: DSS2, SDSS, GALEX, IRAS, Hydrogen α, X-Ray, Astrophoto, Sky Map, Articles and images Ghost of a Dwarf Galaxy (Fossils of the Hierarchical Formation of the Nearby Spiral Galaxy NGC 5907) Astronomy Picture of the Day: NGC 5907 (2008 June 19 ) Fossils of the Hierarchical Formation of the Nearby Spiral Galaxy NGC5907 (arXiv:0805.1137) SEDS – NGC 5907 Hunting ghosts Hunting ghosts: the iconic stellar stream(s) around NGC 5907 under scrutiny

Illustrations

Worked examples

Example 1 — a first encounter with NGC 5907

Start with the simplest possible case. Write down what NGC 5907 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 5907 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 5907 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 5907

In research: NGC 5907 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 5907 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 5907 is common in secondary-school and first-year university syllabi. It links to neighbouring topics Astronomical objects discovered in 1788, Discoveries by William Herschel, Draco (constellation), so understanding it makes those chapters shorter.
In everyday life: Look for NGC 5907 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 5907 in 20 minutes

Read the reference excerpt below once, without taking notes.
Close the page and write down what NGC 5907 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 5907 out loud to somebody else — or to Teacher Smith in the lgStudy chat.

Frequently asked questions

What is NGC 5907 in simple terms?

Why does NGC 5907 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 5907?

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 5907.