science

North Ray (crater)

North Ray (crater) 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 North Ray (crater) rather than just read about it. In short: North Ray crater is a small crater in the Descartes Highlands of the Moon visited by the astronauts of Apollo 16. The name of the crater was formally adopted by the IAU in 1973.

Key takeaways

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

Reference excerpt

North Ray crater is a small crater in the Descartes Highlands of the Moon visited by the astronauts of Apollo 16. The name of the crater was formally adopted by the IAU in 1973. It is the largest crater sampled by astronauts during the Apollo program. The Apollo 16 Lunar Module (LM) Orion landed between North Ray and South Ray craters on April 21, 1972. The astronauts John Young and Charles Duke explored the area between the craters over the course of three EVAs using a Lunar Roving Vehicle, or rover. They visited North Ray on EVA 3, at station 11, about 4.4 km north of the landing site. On the way, they drove along the rim of the similar sized but older crater Palmetto, which is approximately 3 km south of North Ray. North Ray crater is approximately 1 km in diameter and approximately 240 m deep. The astronauts observed that the upper 50 m of the slope is gentle, but that it becomes steep below 50 m, and they could not observe the bottom. The inner slopes are covered by boulders up to 5 m across. A huge (10 m high x 20 m long) boulder, known as House Rock, lies near the southeastern rim. A smaller boulder that is almost certainly a fragment of House Rock is officially known as South Boulder, but unofficially known as Outhouse Rock. The ray system, which can be seen from orbit, was not obvious on the ground. North Ray cuts into the Cayley Formation of Imbrian age, but the crater itself is much younger, of Copernican age, based on the presence of rays. (See also section on age below.)

Gallery

Age

Based on sample 67955, a noritic anorthosite collected from Outhouse Rock, the impact that created North Ray crater was about 50 million year ago. This is based on the measured duration of the rock's exposure to cosmic rays. The rock itself is dated at 4.20 ± 0.07 b.y. by Sm/Nd radiometric dating.

Samples

The following samples were collected from North Ray Crater (Station 11), as listed in Table 6-II of the Apollo 16 Preliminary Science Report, which does not include samples smaller than 25 g weight (of which there were many). Sample type, lithology, and descriptions are from the Lunar Sample Atlas of the Lunar and Planetary Institute.

References

External links Geology of North Ray Crater, Section D2 of Geological Survey Professional Paper 1048, by George E. Ulrich. 1981. Apollo 16 Traverses, 78D2S2(25), Lunar and Planetary Institute

Illustrations

North Ray (crater): Planimetric map of Station 11 from the Apollo 16 Preliminary Science Report. X indicates sample locations, 5-digit numbers are LRL sample numbers, rectangle is lunar rover (dot indicates TV camera), black spots are large rocks, dashed lines are crater rims or other topographic features, and triangles are panorama stations. — Planimetric map of Station 11 from the Apollo 16 Preliminary Science Report. X indicates sample locations, 5-digit numbers are LRL sample numbers, rectangle is lunar rover (dot indicates TV camera), black spots are large rocks, dashed lines are crater rims or other topographic features, and triangles are panorama stations.

Worked examples

Example 1 — a first encounter with North Ray (crater)

Start with the simplest possible case. Write down what North Ray (crater) 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 North Ray (crater) 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 North Ray (crater) 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 North Ray (crater)

In research: North Ray (crater) 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 North Ray (crater) 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: North Ray (crater) is common in secondary-school and first-year university syllabi. It links to neighbouring topics Apollo 16, Impact craters on the Moon, LQ20 quadrangle, so understanding it makes those chapters shorter.
In everyday life: Look for North Ray (crater) 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 “North Ray (crater)” →

Affiliate

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

How to study North Ray (crater) in 20 minutes

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

Frequently asked questions

What is North Ray (crater) in simple terms?

North Ray crater is a small crater in the Descartes Highlands of the Moon visited by the astronauts of Apollo 16. The name of the crater was formally adopted by the IAU in 1973.

Why does North Ray (crater) 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 North Ray (crater)?

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 North Ray (crater).