astronomy

NGC 2110

NGC 2110 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 2110 rather than just read about it. In short: NGC 2110 is a lenticular galaxy located in the constellation Orion. It is located at a distance of about 120 million light years from Earth, which, given its apparent dimensions, means that NGC 2110 is about 90,000 light years across.

Key takeaways

NGC 2110 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 2110 to a quantity you can measure, compute or draw — that is where exam questions come from.
Reproduce the core statement of NGC 2110 from memory before moving on to harder problems.

Reference excerpt

NGC 2110 is a lenticular galaxy located in the constellation Orion. It is located at a distance of about 120 million light years from Earth, which, given its apparent dimensions, means that NGC 2110 is about 90,000 light years across. It was discovered by William Herschel on October 5, 1785. It is a Seyfert galaxy.

Characteristics NGC 2110 has been categorised as a lenticular galaxy, but it had been categorised as an elliptical galaxy in the past. Images by Hubble Space Telescope revealed the presence of curved dust lanes about one arcsecond west of the nucleus. A bar of material measuring 90 by 35 parsec has been found in the nucleus in infrared. Four star clusters have been found in the circumnuclear region by the Keck Observatory in the near infrared that form a semicircular structure with a diameter of 90 parsecs, while observations by Gemini Observatory indicate the presence of ring with stars of intermediate age (100–700 million years) with diameter of 140 parsecs. Closer to the nucleus, the star population is predominately old.

Active nucleus

The nucleus of NGC 2110 has been found to be active, as it a bright source of X-rays, and it has been categorised as a type II Seyfert galaxy. Type 2 Seyfert galaxies are characterised by the presence of narrow emission lines, but a broad double-peaked H-alpha emission line has been detected indicating the presence of a broad line region that is hidden by a dust torus. The most accepted theory for the energy source of active galactic nuclei is the presence of an accretion disk around a supermassive black hole. The mass of the black hole in the centre of NGC 2110 is estimated to be 109.29 (1.95 billion) M☉ based on velocity dispersion or 2×108 M☉ when using the M–sigma relation. NGC 2110 has been found to emit X-rays. The X-ray spectrum is similar to that of Seyfert 1 galaxies that is obstructed by a complex absorber, with column densities between 4 and 30 × 1022/cm2 as measured by BeppoSAX. The presence of a patchy absorber around the nucleus along with a uniform one of lower column density was confirmed with observations made by Chandra X-ray Observatory, XMM Newton, and Suzaku. Although the FeKα line is detected, there is no detectable reflection element. The line appears to come from two components, one from distant Compton-thick material and one variable from material close to the black hole. The temperature of the hot corona of the nucleus is estimated to be 75+20−15 keV. When observed in radio waves, the galaxy features radio emission that extends for 4 arcseconds. The centre of the emission coincides with the nucleus, and from it emanate two jets, one north and one south, with S-shaped morphology. Similarly, north of the nucleus has been found in OIII and H-alpha+NII imaging a narrow strongly curved outflow that is one arcsecond long and looks like a jet. H-alpha imaging also reveals the presence of ionised gas in an s-shaped pattern that extends for 4 arcseconds north and south of the nucleus. In the region 4 arcseconds north of the nucleus, just beyond the end of the radio jet, has been found soft X-rays emission by Chandra X-ray Observatory. There is also soft X-rays emission south of the nucleus that extends for 30 arcseconds. Gas kinematics of the central region of NGC 2110 indicate that there is an inflow of cold gas of 2.2 × 10−2 M☉ per year while the outflow of gas is estimated to be 0.9 M☉ or 0.5 M☉ per year. The outflow causes gas to be blueshifted by 100 km/s to the southwest of the nucleus and to be redshifted by 40 km/s to the northeast. Other kinematic components in the central region of the galaxy are a cold gas disk, with velocity dispersion of 60–90 km/s, a hot gas disk, with velocity dispersion of 220–600 km/s, and a cloud of ionised gas 1–4 arcseconds north of the nucleus. The region of the north ionised cloud is devoid of CO 2–1 emission.

See also NGC 1386 - a similar Seyfert 2 galaxy

References

External links

NGC 2110 on WikiSky: DSS2, SDSS, GALEX, IRAS, Hydrogen α, X-Ray, Astrophoto, Sky Map, Articles and images NGC 2110 on SIMBAD

Illustrations

Worked examples

Example 1 — a first encounter with NGC 2110

Start with the simplest possible case. Write down what NGC 2110 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 2110 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 2110 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 2110

In research: NGC 2110 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 2110 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 2110 is common in secondary-school and first-year university syllabi. It links to neighbouring topics Astronomical objects discovered in 1785, Discoveries by William Herschel, Lenticular galaxies, so understanding it makes those chapters shorter.
In everyday life: Look for NGC 2110 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 2110 in 20 minutes

Read the reference excerpt below once, without taking notes.
Close the page and write down what NGC 2110 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 2110 out loud to somebody else — or to Teacher Smith in the lgStudy chat.

Frequently asked questions

What is NGC 2110 in simple terms?

Why does NGC 2110 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 2110?

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 2110.