The Sun, our star

Tests: 4 of 11 right · Exam: 2 of 4 right · Kind: plain · Understood: 6 of 15 · Run: 2026-10-18, commit f3c23ea72

Lesson 1 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 ✓

my mate says the Sun's just a massive bonfire up there. right?

1. No, it shines by nuclear fusion, nothing burns with oxygen — ← Mova's choice · ✓ the right answer · no support
2. No, it is a mirror reflecting other stars — no support
3. Yes, and it will burn out next century — no support
4. Yes, it burns just like wood on a fire, only very much bigger — no support

Why: Nothing it remembers matched the question, so it guessed: it took the first option shown. · the question and its options parsed, with trees and pragmatics

Test 2 · wrong ✗

If the Sun suddenly switched off, how long would it be before we noticed the dark?

1. At that very same instant, because light is instant — ← Mova's choice · no support
2. Never, because the Moon would keep us lit up instead — no support
3. About a year later, when the Earth goes round once — no support
4. About 8 minutes, the time light takes to reach us — ✓ 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

Test 3 · wrong ✗

If the Sun is just an ordinary star, why does it look so much bigger and brighter than the others?

1. Stars only shine at night when the Sun is off — no support
2. The other stars are only small lamps in the sky — no support
3. It is very close; the other stars are suns much further away — ✓ the right answer · no support
4. It really is the biggest star in the universe — ← Mova's choice · score 5

Why: It took the question to ask why something happens (its cause). It chose option 4 with score 5, the only option with support. Its support: lesson 1, line 7: «The Sun is a star, an ordinary yellow dwarf, and it holds about 99.8 percent of all the mass in the Solar System.», reached through the option's own match among the sentences about the question's things. What matched: the same doer «sun» (+2); the same thing acted on «star» (+2); the same light verb (be, have, do, get, go) (+1). The right option, 3, found no support in what it remembers. · the question and its options parsed, with trees and pragmatics

Test 4 · right ✓

Why do sunspots look black if they are still thousands of degrees hot?

1. The rest of the Sun around them is even brighter — ← Mova's choice · ✓ the right answer · score 8
2. They are covered in thick black smoke and ash from fires — no support
3. They are cold, dead parts of the Sun — no support
4. They are holes showing empty space behind — no support

Why: It took the question to ask why something happens (its cause). It chose option 1 with score 8, the only option with support. Its support: lesson 1, line 13: «Sunspots are darker, cooler patches where strong magnetic fields stop hot gas rising; they look black only because the rest of the Sun is brighter, and many ar…», reached through the cause of the sentence the question matched. What matched: the same doer «rest» (+4); the same property (+2); the same light verb (be, have, do, get, go) (+2). · the question and its options parsed, with trees and pragmatics

Test 5 · right ✓

Lily wants to look at sunspots through Dad's binoculars. What should she do?

1. Do it, but only for a few seconds — no support
2. Do it with sunglasses on — no support
3. Not do it; look only with proper solar filters or projection — ← Mova's choice · ✓ the right answer · score 8
4. Do it at midday, when the Sun is clearest and the spots are biggest — no support

Why: It took the question to ask what is done. It chose option 3 with score 8, the only option with support. Its support: lesson 1, line 13: «Sunspots are darker, cooler patches where strong magnetic fields stop hot gas rising; they look black only because the rest of the Sun is brighter, and many ar…», reached through the remembered sentence the question matched. What matched: it fills the role the question asks for (+6); the same action «look» (+4). Against it: a different doer (counts against) (-2). · the question and its options parsed, with trees and pragmatics

Test 6 · wrong ✗

Why might a big solar storm worry an electricity company?

1. It can make the Sun go dark for a whole week or more — ← Mova's choice · no support
2. It can disturb power grids and knock out supply — ✓ the right answer · no support
3. It can stop the Earth from turning for a few hours — no support
4. It can heat the cables in the ground until they melt — no support

Why: Nothing it remembers matched the question, so it guessed: it took the first option shown. · the question and its options parsed, with trees and pragmatics

Test 7 · right ✓

In a cartoon, the Sun is a cheerful planet with a face. What is wrong?

1. The Sun is really a moon — no support
2. The Sun is a star, not a planet — ← Mova's choice · ✓ the right answer · score 10
3. Nothing, the Sun is the biggest planet — no support
4. The Sun is actually smaller than the Earth — no support

Why: It took the question to ask which statement is true. It chose option 2 with score 10, the only option with support. Its support: lesson 1, line 7: «The Sun is a star, an ordinary yellow dwarf, and it holds about 99.8 percent of all the mass in the Solar System.», reached through the remembered sentence the question matched. What matched: the same doer «sun» (+4); the same thing acted on «star» (+4); the same light verb (be, have, do, get, go) (+2). · the question and its options parsed, with trees and pragmatics

Test 8 · wrong ✗

My granddad says he saw the northern lights from England in 2024. Could that be true?

1. Yes, but only because it was winter — ← Mova's choice · no support
2. No, aurorae happen only at the North Pole — no support
3. Yes, near solar maximum aurorae were seen much further south than usual — ✓ the right answer · no support
4. No, aurorae are just a story from films — 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 9 · wrong ✗

Which is surprising about the Sun's temperatures?

1. Sunspots are the hottest part of the Sun — ← Mova's choice · no support
2. The Sun is coldest at its centre — no support
3. The surface is hotter than the core — no support
4. The thin outer corona is far hotter than the visible surface — ✓ the right answer · no support

Why: Nothing it remembers matched the question, so it guessed: it took the first option shown. · the question and its options parsed, with trees and pragmatics

Test 10 · wrong ✗

How did astronomers first notice that the Sun spins?

1. By hearing it whirr and hum through a big telescope — no support
2. By seeing its rings go round — no support
3. By noticing the year getting shorter — ← Mova's choice · score 8
4. By watching sunspots move across its face — ✓ the right answer · score 6

Why: It took the question to ask what something is like. It chose option 3 with score 8, against 6 for the next best. Its support: lesson 1, line 19: «The Sun is a ball of gas, so different parts spin at different speeds: about 25 days at its equator and about 35 days near its poles; astronomers first noticed…», reached through the remembered sentence the question matched. What matched: the same action «notice» (+4); the same doer «astronomers» (+4). The right option, 4, scored 6. · the question and its options parsed, with trees and pragmatics

Test 11 · wrong ✗

ugh the Sun's gonna explode tomorrow, saw it on TikTok lol

1. Yes, scientists say it will blow up any day — score 2
2. No, it will just switch off next year — ← Mova's choice · score 3
3. No, it is halfway through its life and will not explode; it will become a red giant in billions of years — ✓ the right answer · no support
4. Yes, it explodes every 11 years — score 3

Why: It took the question to ask which statement is true. It chose option 2 with score 3, tied with another option at 3 (the first shown, or the one claiming less beyond what it knows, wins). Its support: lesson 1, line 18: «The Sun is about 4.6 billion years old, roughly halfway through its life; in about 5 billion years it will swell into a red giant and end as a white dwarf.», reached through the option's own match among the sentences about the question's things. What matched: the same doer «sun» (+2); the same property (+1). The right option, 3, found no support in what it remembers. · the question and its options parsed, with trees and pragmatics

Exam question 1 · formal language · wrong ✗

Identify the process by which energy is generated within the core of the Sun.

1. Reflection of light received from other stars — ← Mova's choice · no support
2. Combustion of gases in the presence of oxygen — no support
3. Gravitational friction between the planets — no support
4. Nuclear fusion of hydrogen into helium — ✓ 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 2 · formal language · right ✓

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

1. Approximately eight minutes and twenty seconds — ← Mova's choice · ✓ the right answer · no support
2. It is received at once, without any delay whatsoever — no support
3. Approximately one hour, the time of a short journey — no support
4. Approximately one second, about as long as a blink — 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 · wrong ✗

Which of the following statements most accurately characterises sunspots?

1. Shadows cast upon the Sun by the passage of the planets — ← Mova's choice · no support
2. Comparatively cool regions in which strong magnetic fields inhibit rising gas — ✓ the right answer · no support
3. Regions in which fusion has permanently ceased — no support
4. Apertures through which the interior of the Sun may be observed — 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 · right ✓

Select the response consistent with the established facts concerning the future evolution of the Sun.

1. In some five billion years it shall expand into a red giant — ← Mova's choice · ✓ the right answer · no support
2. It shall collapse into a black hole within the present century — no support
3. It shall remain wholly unchanged in perpetuity — no support
4. It shall explode as a supernova within a thousand years — no support

Why: Nothing it remembers matched the question, so it guessed: it took the first option shown. · the question and its options parsed, with trees and pragmatics

This page in Markdown → https://md.mova.elamur.ai/free/en/school-run/space/1-the-sun-our-star/