Distances and light years

Tests: 4 of 11 right · Exam: 1 of 4 right · Kind: ★ · Understood: 10 of 15 · Run: 2026-10-18, commit f3c23ea72

Lesson 22 of the space course of Mova's primary school, as Mova's small model took its tests: it had read this lesson and the ones before it and learned from their exercises. Each test shows the options in the order the student saw them, its choice, the right answer, the score of every option and why it chose. The lesson itself, sentence by sentence with trees and pragmatics: the lesson in the corpora.

Every question of this lesson and each of its options parsed by Mova, with trees and pragmatics: the lesson's questions in the corpora.

Test 1 · ★ · right ✓

Zoe says "a light year is a really long time". What's wrong?

1. A light year is a distance, not a time — ← Mova's choice · ✓ the right answer · score 9
2. Nothing, it is just a year of time measured in space — no support
3. It is actually quite a short time, about a month — no support
4. It is a speed, how fast light goes, not a time — no support

Why: It took the question to ask which statement is true. It chose option 1 with score 9, the only option with support. Its support: lesson 22, line 6: «A light year is a distance, not a time: it is how far light travels in a year, about 9.5 trillion kilometres.», reached through the remembered sentence the question matched. What matched: the same doer «light year» (+4); the same thing acted on «distance» (+3); the same light verb (be, have, do, get, go) (+2). · the question and its options parsed, with trees and pragmatics

Test 2 · ★ · wrong ✗

If the Sun suddenly went out, how soon would we notice from Earth?

1. After about 1.3 seconds — ← Mova's choice · no support
2. After a whole year — no support
3. After about 8 minutes 20 seconds — ✓ the right answer · no support
4. At that very same moment — no support

Why: No option found support in what it remembers, so it guessed: it took the first option shown. · the question and its options parsed, with trees and pragmatics

Test 3 · ★ · wrong ✗

Polaris is about 430 light years away. If it had blown up 100 years ago, what would we see tonight?

1. Polaris exploding right now — no support
2. Polaris getting brighter every night — ← Mova's choice · score 4
3. A dark gap where Polaris was — no support
4. Polaris still shining as normal — ✓ the right answer · no support

Why: It took the question to ask what it is done to. It chose option 2 with score 4, the only option with support. Its support: lesson 22, line 15: «Bright stars are at very different distances: Sirius is about 8.6 light years away, Vega about 25, Polaris about 430, and Deneb probably more than 1,500.», reached through the same lesson line as the sentence the question matched. What matched: the same doer «bright stars» (+3); the same property (+1). The right option, 4, found no support in what it remembers. · the question and its options parsed, with trees and pragmatics

Test 4 · ★ · wrong ✗

bro says we'll fly to the nearest star in like 10 years with Voyager. lol?

1. No, at Voyager's speed it would take about 75,000 years — ✓ the right answer · no support
2. No, it would take about 750 years — no support
3. Yes, Voyager will get there in 2036 if it keeps going straight — ← Mova's choice · score 6
4. Yes, it is only 4 light minutes away — score 6

Why: It took the question to ask which statement is true. It chose option 3 with score 6, tied with another option at 6 (the first shown, or the one claiming less beyond what it knows, wins). Its support: lesson 21, line 2: «On summer evenings in Britain three bright stars, Vega, Deneb and Altair, make a huge triangle almost straight overhead: the Summer Triangle.», reached through the option's own match among the sentences about the question's things. What matched: the same doer «three bright stars» (+4); the same property (+2). The right option, 1, found no support in what it remembers. · the question and its options parsed, with trees and pragmatics

Test 5 · ★ · right ✓

Which is true about bright stars in the sky?

1. The brightest ones are always the nearest ones to us — no support
2. They are all the same distance away from the Earth — score 7
3. They are at very different distances from us — ← Mova's choice · ✓ the right answer · score 10
4. They all sit together on the inside of one big sphere — score 5

Why: It took the question to ask which statement is true. It chose option 3 with score 10, against 7 for the next best. Its support: lesson 22, line 15: «Bright stars are at very different distances: Sirius is about 8.6 light years away, Vega about 25, Polaris about 430, and Deneb probably more than 1,500.», reached through the remembered sentence the question matched. What matched: the same doer «bright stars» (+4); the same circumstance (+4); the same light verb (be, have, do, get, go) (+2). · the question and its options parsed, with trees and pragmatics

Test 6 · ★ · right ✓

Talking to astronauts on the Moon, why is there a short delay before they answer?

1. The Moon's thin air slows the sound of their voices — no support
2. Radio signals take about 1.3 seconds each way — ← Mova's choice · ✓ the right answer · score 3
3. The astronauts think slowly in low gravity — no support
4. Their radios are very old — no support

Why: It took the question to ask why something happens (its cause). It chose option 2 with score 3, the only option with support. Its support: lesson 22, line 7: «Light from the Moon takes about 1.3 seconds to reach us, and radio signals travel just as fast, so a call to astronauts on the Moon has a short delay, and sunl…», reached through the same lesson line as the sentence the question matched. What matched: the same action «take» (+2); the same property (+2). Against it: a different doer (counts against) (-1). · the question and its options parsed, with trees and pragmatics

Test 7 · ★ · wrong ✗

In a film, a ship flies "100 light years to the next star in two minutes". Why is it not real?

1. Light years are only used for measuring time, not distance — no support
2. Stars are much closer than that, so the trip is too short — ← Mova's choice · score 5
3. Ships cannot fly in the dark between stars without sunlight — no support
4. Nothing we know can travel faster than light — ✓ the right answer · score 1

Why: It took the question to ask why something happens (its cause). It chose option 2 with score 5, against 1 for the next best. Its support: lesson 17, line 6: «The Sun is a star, an ordinary one, and it looks so different from the others only because it is about 270,000 times closer than the next nearest star.», reached through the option's own match among the sentences about the question's things. What matched: the same doer «star» (+3); the same property (+1); the same light verb (be, have, do, get, go) (+1). The right option, 4, scored 1. · the question and its options parsed, with trees and pragmatics

Test 8 · ★ · wrong ✗

Deneb looks about as bright as Vega. What does that tell us?

1. Deneb must give out far more light, as it is much farther away — ✓ the right answer · score 3
2. Deneb and Vega must be exactly the same distance away from the Earth — ← Mova's choice · score 4
3. Deneb is a planet, not a star — score 3
4. Deneb is nearer but smaller — no support

Why: It took the question to ask what it is done to. It chose option 2 with score 4, against 3 for the next best. Its support: lesson 14, line 7: «Uranus and Neptune look blue-green and blue because methane gas in their air absorbs red light.», reached through a sentence linked to the one the question matched. What matched: it fills the role the question asks for (+3); the same thing acted on «red light» (+2). Against it: a different doer (counts against) (-1). The right option, 1, scored 3. · the question and its options parsed, with trees and pragmatics

Test 9 · ★ · right ✓

Will the Moon fly off into space next year then, if it's moving away?

1. Yes, it will leave us within ten years and drift off into space — no support
2. No, it is actually getting closer to the Earth every single year — no support
3. No, it moves away only about 3.8 centimetres a year — ← Mova's choice · ✓ the right answer · score 9
4. Yes, it moves away about a kilometre a day, faster and faster — score 9

Why: It took the question to ask which statement is true. It chose option 3 with score 9, tied with another option at 9 (the first shown, or the one claiming less beyond what it knows, wins). Its support: lesson 22, line 16: «The Moon is moving away from Earth by about 3.8 centimetres a year, about as fast as fingernails grow.», reached through the option's own match among the sentences about the question's things. What matched: the same doer «moon» (+4); the same action «move away» (+3); the same property (+2). · the question and its options parsed, with trees and pragmatics

Test 10 · ★ · wrong ✗

Why is the football model of the solar system hard to fit in a school field?

1. The Sun football would be too heavy — ← Mova's choice · no support
2. Even the nearest star would be thousands of kilometres off — ✓ the right answer · no support
3. The peppercorn would be far too big to fit on the field at all — no support
4. The planets would all touch each other — no support

Why: No option found support in what it remembers, so it guessed: it took the first option shown. · the question and its options parsed, with trees and pragmatics

Test 11 · ★ · wrong ✗

How far is 1 AU in kilometres?

1. About 384,000 — ← Mova's choice · no support
2. About 26 billion — no support
3. About 9.5 trillion — no support
4. About 150 million — ✓ the right answer · no support

Why: No option found support in what it remembers, so it guessed: it took the first option shown. · the question and its options parsed, with trees and pragmatics

Exam question 1 · formal language · wrong ✗

Which of the following statements most accurately characterises the unit designated the light year?

1. It is a unit of brightness for stars — ← Mova's choice · score 2
2. It is a unit of speed equal to that of light — score 2
3. It is a unit of distance equal to about 9.5 trillion kilometres — ✓ the right answer · score 2
4. It is a unit of time equal to one Earth year, used for star travel — score 2

Why: It took the question to ask who or what does it. It chose option 1 with score 2, tied with another option at 2 (the first shown, or the one claiming less beyond what it knows, wins). Its support: lesson 22, line 14: «Professional astronomers often use the parsec, about 3.26 light years, a unit based on how stars seem to shift as Earth orbits the Sun.», reached through the remembered sentence the question matched. What matched: it fills the role the question asks for (+3); the same doer «unit» (+1). Against it: a different thing acted on (counts against) (-2). The right option, 3, scored 2. · the question and its options parsed, with trees and pragmatics

Exam question 2 · formal language · wrong ✗

Ascertain the approximate interval required for light emitted by the Sun to reach the Earth.

1. About twenty-four hours — ← Mova's choice · no support
2. About four years and two months — no support
3. About eight minutes and twenty seconds — ✓ the right answer · no support
4. About one and three-tenths seconds — no support

Why: No option found support in what it remembers, so it guessed: it took the first option shown. · the question and its options parsed, with trees and pragmatics

Exam question 3 · formal language · right ✓

Identify the star, other than the Sun, situated nearest to the Earth.

1. Proxima Centauri — ← Mova's choice · ✓ the right answer · no support
2. Polaris — no support
3. Sirius — no support
4. Betelgeuse — no support

Why: No option found support in what it remembers, so it guessed: it took the first option shown. · the question and its options parsed, with trees and pragmatics

Exam question 4 · formal language · wrong ✗

Select the response that is consistent with the established facts concerning the observation of a distant star.

1. The light observed departed from the star long ago — ✓ the right answer · no support
2. The star is invariably observed as it will be in future — ← Mova's choice · score 6
3. The light observed departs from the star at that instant — no support
4. The light of stars requires no time to travel — score 6

Why: It took the question to ask which statement is true. It chose option 2 with score 6, tied with another option at 6 (the first shown, or the one claiming less beyond what it knows, wins). Its support: lesson 11, line 1: «Jupiter is like a king with a huge court: more than 90 moons go round it, and telescopes keep finding new tiny ones.», reached through the remembered sentence the question matched. What matched: the same action «find» (+3); the same thing acted on «new tiny ones» (+3). The right option, 1, found no support in what it remembers. · the question and its options parsed, with trees and pragmatics

This page in Markdown → https://md.mova.elamur.ai/free/en/school-run/space/22-distances-and-light-years/