astronomy

H1426+428

H1426+428 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 H1426+428 rather than just read about it. In short: H1426+428 also known as 1ES 1426+428, is a high-frequency peaked BL Lacertae object (HBL) located in the constellation of Boötes. It is located at a relatively high redshift of (z) 0.129, and was discovered in 1984 by astronomers who presented a catalogue of X-ray sources taken with the HEAO 1 satellite.

Key takeaways

H1426+428 belongs to astronomy; place it in that map before memorising details.
Learn the definition first, then one example that makes the definition concrete.
Connect H1426+428 to a quantity you can measure, compute or draw — that is where exam questions come from.
Reproduce the core statement of H1426+428 from memory before moving on to harder problems.

Reference excerpt

H1426+428 also known as 1ES 1426+428, is a high-frequency peaked BL Lacertae object (HBL) located in the constellation of Boötes. It is located at a relatively high redshift of (z) 0.129, and was discovered in 1984 by astronomers who presented a catalogue of X-ray sources taken with the HEAO 1 satellite. H1426+428 is classified as a blazar. It is also a distant source of TeV gamma rays. It has low power and a synchrotron peak that is above 100 KeV. Furthermore, H1426+428 is possibly hosted in an elliptical galaxy and is luminous in X-ray bands. It has a 2-6 keV luminosity of ~1044 erg s−1. The gamma emission in H1426+428 is found to have an average flux. Its spectrum is very steep and shows a differential spectral index of γ = -3.60 ± 0.57, when observed by the Cosmic Anisotropy Telescope (CAT) in Very High energy gamma ray bands between 1998 and 2000. This steep spectrum is mainly contributed by the absorption of gamma rays in the intergalactic medium or by diffused cosmic infrared background. In 2002, H1426+428 exhibited variability in the 3-24 keV X-ray spectra. However in 2006, it was in a period of X-ray inactivity, showing no gamma rays, when observed by CELESTE Cherenkov telescope . The Tev activity in H1426+428 only increased just before 2008, with it experiencing flare activity for four days in 2009. A long-term X-ray flare was detected in H1426+428 in January 2021 by the X-ray telescope onboard Neil Gehrels Swift Observatory. This was followed by a very high energy gamma ray flux in March 2021. H1426+428 has a compact radio core with a ~ 17 mJy flux density. In additional, it has a faint radio jet extending towards northwest with a project position angle of -25°. There is also a faint radio halo that is surrounding the radio core as well but it has weak radio and optical polarization.

References

External links H1423+428 on SIMBAD H1423+428 on NASA/IPAC Extragalactic Database

Illustrations

Worked examples

Example 1 — a first encounter with H1426+428

Start with the simplest possible case. Write down what H1426+428 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 H1426+428 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 H1426+428 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 H1426+428

In research: H1426+428 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 H1426+428 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: H1426+428 is common in secondary-school and first-year university syllabi. It links to neighbouring topics Active galaxies, Astronomical objects discovered in 1984, BL Lacertae objects, so understanding it makes those chapters shorter.
In everyday life: Look for H1426+428 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 H1426+428 in 20 minutes

Read the reference excerpt below once, without taking notes.
Close the page and write down what H1426+428 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 H1426+428 out loud to somebody else — or to Teacher Smith in the lgStudy chat.

Frequently asked questions

What is H1426+428 in simple terms?

Why does H1426+428 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 H1426+428?

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 H1426+428.