astronomy

Red Spider Nebula

Red Spider Nebula 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 Red Spider Nebula rather than just read about it. In short: The Red Spider Nebula (also catalogued as NGC 6537) is a planetary nebula located in the northwest of the constellation Sagittarius. It was discovered by Edward Charles Pickering on 15 July 1882.

Key takeaways

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

Reference excerpt

The Red Spider Nebula (also catalogued as NGC 6537) is a planetary nebula located in the northwest of the constellation Sagittarius. It was discovered by Edward Charles Pickering on 15 July 1882. The nebula has a prominent two-lobed shape, possibly due to a binary companion or magnetic fields and has an S-shaped symmetry of the lobes – the lobes opposite each other appear similar. This is believed to be due to the presence of a companion to the central white dwarf. However, the gas walls of the two lobed structures are not at all smooth, but rather are rippled in a complex way. The central white dwarf, the remaining compact core of the original star, produces a powerful and hot (≈10,000 K) wind blowing with a speed of 300 kilometers per second, which has generated waves 100 billion kilometres high. The waves are generated by supersonic shocks formed when the local gas is compressed and heated in front of the rapidly expanding lobes. Atoms caught in the shocks radiate a visible light. These winds are what give this nebula its unique 'spider' shape and also contribute to the expansion of the nebula. The star at the center of the Red Spider Nebula is surrounded by a dust shell making its exact properties hard to determine. Its surface temperature is probably 150,000–250,000 K, although a temperature of 340,000 K or even 500,000 K is not ruled out, making it among the hottest white dwarf stars known. Observations with Hubble and JWST NIRCam showed hot (around 1000 K) circumstellar dust around the central star. The researchers propose that interactions between the progenitor star and a close companion are responsible for many features of NGC 6537. The central binary may be surrounded by a circumbinary disk. Non-detection in X-rays suggests that the companion is less massive than the Sun. The Red Spider Nebula lies near the constellation of Sagittarius. Its distance has been variously estimated as 1,900 light-years or, more likely, 3,000–8,000 light-years. A research team studied the nebula with Hubble, ALMA, Chandra and JWST. The core of the nebula is shown to be consistent with a highly asymmetric ring or irregular spiral with a radius of 5 arcseconds (0.04 parsec). The core is surrounded by an equatorial molecular torus with a deprojected radius of around 0.13 parsec and an inclination of 38°. The torus has an outflow velocity of 13 km/s and an age of around 10,000 years. Molecular hydrogen imaging showed the full extent of the polar lobes, showing that they are closed bubble-like structure with an extent of around 100 arcseconds (deprojected around 0.9 parsec). The lobes have an outflow velocity of around 300 km/s and a dynamical age of around 3700 years. The lobes have an S-shape in iron [Fe II] imaging, which is also seen in NGC 6302. This likely traces fast shocks from a collision between an active, collimated stellar wind with slower-moving material forming the polar lobe rims.

Gallery

See also List of NGC objects (6001–7000)

References

External links Media related to NGC 6537 at Wikimedia Commons Red Spider Nebula at ESA/Hubble White dwarf sends ripples through Red Spider Nebula at Space.com NASA Astronomy Picture of the Day: The Red Spider Planetary Nebula (6 January 1998) NASA Astronomy Picture of the Day: The Red Spider Planetary Nebula (19 April 2017)

Illustrations

Worked examples

Example 1 — a first encounter with Red Spider Nebula

Start with the simplest possible case. Write down what Red Spider Nebula 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 Red Spider Nebula 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 Red Spider Nebula 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 Red Spider Nebula

In research: Red Spider Nebula 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 Red Spider Nebula 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: Red Spider Nebula is common in secondary-school and first-year university syllabi. It links to neighbouring topics Astronomical objects discovered in 1882, ESO objects, NGC objects, so understanding it makes those chapters shorter.
In everyday life: Look for Red Spider Nebula 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 Red Spider Nebula in 20 minutes

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

Frequently asked questions

What is Red Spider Nebula in simple terms?

The Red Spider Nebula (also catalogued as NGC 6537) is a planetary nebula located in the northwest of the constellation Sagittarius. It was discovered by Edward Charles Pickering on 15 July 1882.

Why does Red Spider Nebula 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 Red Spider Nebula?

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 Red Spider Nebula.