astronomy

PKS 1127−145

PKS 1127−145 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 PKS 1127−145 rather than just read about it. In short: PKS 1127−145 is a radio-loud quasar located in the constellation of Crater. This is a Gigahertz Peaked Spectrum object with a redshift of (z) 1.187, first discovered by astronomers in 1966.

Key takeaways

PKS 1127−145 belongs to astronomy; place it in that map before memorising details.
Learn the definition first, then one example that makes the definition concrete.
Connect PKS 1127−145 to a quantity you can measure, compute or draw — that is where exam questions come from.
Reproduce the core statement of PKS 1127−145 from memory before moving on to harder problems.

Reference excerpt

PKS 1127−145 is a radio-loud quasar located in the constellation of Crater. This is a Gigahertz Peaked Spectrum object with a redshift of (z) 1.187, first discovered by astronomers in 1966. Its radio spectrum appears to be flat making it a flat-spectrum radio quasar, or an FSRQ in short.

Description PKS 1127−145 displays blazar-like behavior. It is known to undergo a period of gamma ray activity, especially in December 2020 where its daily gamma ray flux reached a peak of (E > 100 MeV) of (1.6 ± 0.3) × 10−6 photons cm−2 s−1. Two flares were detected by Fermi-LAT in May and October 2022. The radio structure of PKS 1127−145 is found to be complex. A radio image made by the Very Long Baseline Interferometry (VLBI) shows the object has two components, mainly a bright component and a much weaker component with same brightness temperatures of 1.3 × 1011 Kelvin. No extension is found in northwest direction. There is a presence of a compact core displaying strong increase of flux density with the outermost component being separated into several smaller regions enveloped completely by emission. A stationary feature is also seen located 4 mas from the core via a 22 GHz image taken by VLBI. Circular polarization has also been found in the quasar as well.

X-ray jet

An X-ray jet has been discovered in PKS 1127−145 by Chandra X-ray Observatory. With an estimated length of 300 kiloparsecs, this makes it the longest detected so far in any high redshift quasar. Advanced CCD Imaging Spectrometer also revealed a complex structure in the X-ray jet from the core with bright knots of different morphologies. Two of the knots showed changes in their profiles while the other knot is fainter with presence of X-ray emission scattered over a large area. A more in-depth analysis of the X-ray jet in PKS 1127−145 showed the inner jet of PKS 1127−145 located from the core is found to be extremely polarized and a parallel magnetic field towards the jet's axis. Upon reaching 18 arcseconds from the core, the jet suddenly bends slightly causing the re-brightening of radio emission. In additional, there is a 90° rotation of the magnetic field suggesting it might be compressed to the plane that is found perpendicular to the axis.

References

External links PKS 1127−145 PKS 1127−145 on NASA/IPAC Database

Illustrations

Worked examples

Example 1 — a first encounter with PKS 1127−145

Start with the simplest possible case. Write down what PKS 1127−145 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 PKS 1127−145 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 PKS 1127−145 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 PKS 1127−145

In research: PKS 1127−145 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 PKS 1127−145 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: PKS 1127−145 is common in secondary-school and first-year university syllabi. It links to neighbouring topics Active galaxies, Astronomical objects discovered in 1966, Blazars, so understanding it makes those chapters shorter.
In everyday life: Look for PKS 1127−145 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 PKS 1127−145 in 20 minutes

Read the reference excerpt below once, without taking notes.
Close the page and write down what PKS 1127−145 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 PKS 1127−145 out loud to somebody else — or to Teacher Smith in the lgStudy chat.

Frequently asked questions

What is PKS 1127−145 in simple terms?

PKS 1127−145 is a radio-loud quasar located in the constellation of Crater. This is a Gigahertz Peaked Spectrum object with a redshift of (z) 1.187, first discovered by astronomers in 1966.

Why does PKS 1127−145 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 PKS 1127−145?

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 PKS 1127−145.