science

Ureilite

Ureilite is a science 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 Ureilite rather than just read about it. In short: Ureilite is a rare type of stony meteorite that has a unique mineralogical composition very different from that of other stony meteorites. This dark grey or brownish meteorite type is named after the village Novy Urey (Cyrillic: Новый Урей), Mordovia Republic of Russia, where a meteorite of this type fell on 4 September 1886.

Key takeaways

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

Reference excerpt

Ureilite is a rare type of stony meteorite that has a unique mineralogical composition very different from that of other stony meteorites. This dark grey or brownish meteorite type is named after the village Novy Urey (Cyrillic: Новый Урей), Mordovia Republic of Russia, where a meteorite of this type fell on 4 September 1886. Notable ureilites are the Novo Urei and the Goalpara, also named for the town in which it landed (Goalpara, Assam India). On 7 October 2008, tiny asteroid 2008 TC3 entered Earth's atmosphere and exploded an estimated 37 kilometres (23 mi) above the Nubian Desert in Sudan. Fragments of this asteroid were recovered the following December and were found to be ureilite. Scientists have discovered amino acids in meteorite 2008 TC3 where none were expected, taking into account high temperatures reached in the explosion of about 1000 °C.

Composition A geological name for ureilite would be olivine-pigeonite achondrite. Compared to most other meteorites, ureilites tend to have a high percentage of carbon (average 3% by weight) in the form of graphite and nanodiamonds. The diamonds, which are rarely more than a few micrometres in diameter, are probably the result of high pressure shockwaves produced by collisions of the ureilite parent body with other asteroids. Ureilites can be divided into two subcategories: monomict and polymict. Monomict ureilites are coarse-grained, with olivine usually more abundant than pyroxene. Polymict ureilites are a mixture of clasts of dissimilar composition.

Origin Unknown. Some groups of meteorites come from a single object (i.e. Mars, Moon, 4 Vesta), but no parent body has been found for the ureilites. Before impacting Earth 2008 TC3 was identified as an F-type asteroid. One theory suggests that ureilites were formed in the interior of a parent body with cumulate crystals that formed crystal layers. Support for this comes from some ureilites in which the grains are aligned in a preferred orientation. Another suggestion is that ureilites represent a residuum of unmelted material after a partial melt liquid was drawn off. Yet other ideas are that they are unprocessed materials which never melted or that they are mixtures of carbonaceous chondrite and basaltic rock melts. It remains unclear whether ureilites originated on different parent bodies or in different regions of a single body. The presence of diamonds, which can form from graphite as a result of severe shock metamorphism, hints at a violent impact history. By contrast, a 2018 study of the diamond inclusions in 2008 TC3 concluded that they could only have formed over a relatively long period of time at high pressure, suggesting that "the ureilite parent body was a Mercury- to Mars-sized planetary embryo."

See also Glossary of meteoritics Meteorite classification

References

Illustrations

Worked examples

Example 1 — a first encounter with Ureilite

Start with the simplest possible case. Write down what Ureilite claims or describes in one sentence, then invent the smallest concrete situation in which that sentence is true. In science, 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 Ureilite 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 Ureilite 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 Ureilite

In research: Ureilite appears in science 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 Ureilite 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: Ureilite is common in secondary-school and first-year university syllabi. It links to neighbouring topics Asteroidal achondrites, Meteorite groups, so understanding it makes those chapters shorter.
In everyday life: Look for Ureilite 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 Ureilite in 20 minutes

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

Frequently asked questions

What is Ureilite in simple terms?

Why does Ureilite matter?

Because it connects several science 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 Ureilite?

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 Ureilite.