astronomy

HXMM01

HXMM01 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 HXMM01 rather than just read about it. In short: HXMM01, known more formally as 1HERMES S250 J022016.5−060143, is a starburst galaxy located in the northwestern portion of the constellation Cetus. Discovered in 2013 by a team at the University of California, Irvine, it was discovered that HXMM01 is actually still forming from its two parent galaxies as part of the "brightest, most luminous and most gas-rich submillimeter-bright galaxy merger known." When the merge…

Key takeaways

HXMM01 belongs to astronomy; place it in that map before memorising details.
Learn the definition first, then one example that makes the definition concrete.
Connect HXMM01 to a quantity you can measure, compute or draw — that is where exam questions come from.
Reproduce the core statement of HXMM01 from memory before moving on to harder problems.

Reference excerpt

HXMM01, known more formally as 1HERMES S250 J022016.5−060143, is a starburst galaxy located in the northwestern portion of the constellation Cetus. Discovered in 2013 by a team at the University of California, Irvine, it was discovered that HXMM01 is actually still forming from its two parent galaxies as part of the "brightest, most luminous and most gas-rich submillimeter-bright galaxy merger known." When the merger is complete, HXMM01 will rapidly evolve to become a giant elliptical galaxy with a mass about four times that of the Milky Way. As of 2013, HXMM01 has been observed to form about 2,000 M☉ of stars every year, with an efficiency ten times greater than that of typical galaxies and far more than the Milky Way's 0.68–1.45 M☉ per year.

History of observation A team at the University of California, Irvine, led by Asantha Cooray, was the first to detect and characterize HXMM01 in data from the Herschel space telescope's HerMES instrument. Initially noticed as an "amazing, bright blob" in an otherwise cold region of the cosmos, the galaxy was revealed to be an extremely bright submillimeter galaxy (SMG) after an extensive series of observations across the electromagnetic spectrum. Analyses of the data, published in May 2013, revealed the galaxy to be a merging pair with a mass at least ten times that of the Milky Way.

Physical characteristics With a mass at least 10 times that of the Milky Way, HXMM01 is located at a redshift of 2.307 (corresponding to a distance of about 11 billion light years under the Λ-CDM model of cosmology) and has various physical features that are not characteristic of SMGs. For example, the dust temperature of the galaxy is a relatively high 55 K, 36% more than the 35 K average for star-forming galaxies at similar redshifts. As a result of this extremely high temperature, star formation in HXMM01 is extremely efficient and causes the galaxy to have a relatively high infrared luminosity of 3.2×1013 L☉. HXMM01 has an extremely high rate of star formation of roughly 2,000 M☉, a rate that will cause the nascent galaxy to consume nearly all of its gas and dust within 200 million years. The observation has profound implications for our conception of the formation of giant elliptical galaxies—although the process of formation for dwarf ellipticals had already been determined through analyses of gas density in lower-mass galaxies, the formation of giant elliptical galaxies had eluded description until the discovery of HXMM01. By analyzing HXMM01's rapid rate of star formation, the discovery team was able to deduce that giant elliptical galaxies would be able to form in the Universe at a redshift of about 1.5, corresponding to a distance (and thus observed galactic age) of about 4 billion years.

Illustrations

Worked examples

Example 1 — a first encounter with HXMM01

Start with the simplest possible case. Write down what HXMM01 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 HXMM01 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 HXMM01 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 HXMM01

In research: HXMM01 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 HXMM01 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: HXMM01 is common in secondary-school and first-year university syllabi. It links to neighbouring topics Cetus (constellation), Starburst galaxies, so understanding it makes those chapters shorter.
In everyday life: Look for HXMM01 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.

Ask Teacher Smith questions about this articleOpens your AI tutor with a question about “HXMM01” →

Affiliate

Preply — study more efficiently by working with a personal tutor. 50% off.

How to study HXMM01 in 20 minutes

Read the reference excerpt below once, without taking notes.
Close the page and write down what HXMM01 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 HXMM01 out loud to somebody else — or to Teacher Smith in the lgStudy chat.

Frequently asked questions

What is HXMM01 in simple terms?

Why does HXMM01 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 HXMM01?

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 HXMM01.