Beyond the solar system

Learn it by playing

Answer these questions to earn energy, then fish and explore. No account needed.

For teachers: ready-to-use lesson slides, revision notes, diagrams for Beyond the solar system (KS3 Science, Physics) — use them in your lesson, or run the topic as an interactive class activity your students play as a live game.

Lesson notes

The Universe and Galaxies

The universe contains **billions** of galaxies.
A galaxy contains **billions** of stars.
Our solar system is part of the **Milky Way** galaxy.
The universe formed **13.8 billion years ago** in the **Big Bang**.
Distances to galaxies are measured in **light years**.

Light Years

The speed of light is **300,000,000 m/s**.
A **light year** is the distance light travels in one year.
One light year equals **9.5 × 10¹⁵ m**.
The Andromeda galaxy is **2.5 million light years** away.

Black Holes

At the centre of the Milky Way is a **black hole**.
A black hole forms from the death of a **very massive star**.

Star Life Cycle: Nebula to Main Sequence

All stars begin as a cloud of dust and gas called a **nebula** (mostly hydrogen).
**Gravitational attraction** pulls the dust and gas together.
Pressure and friction cause the temperature to rise greatly.
A **main sequence star** is formed.

Star Life Cycle: Later Stages

When hydrogen runs out, stars expand.
Stars like the Sun become **red giants**; much bigger stars become **red supergiants**.
Red giants leave behind a **white dwarf** that cools to a **black dwarf**.
Red supergiants explode in a **supernova**.
The biggest stars leave a **black hole**; less massive ones leave a **neutron star**.

Star life cycle showing formation from nebula to main sequence, then red giant/white dwarf/black dwarf for Sun-like stars, and red supergiant/supernova/neutron star or black hole for massive stars.

Slides

Step through every slide for this topic — plus flashcards and revision notes — with a free account.

Practice questions

Free preview — 8 of 40 questions. Sign up to see them all.

1.How many galaxies does the universe contain?
Easy
- ABillions
- BThousands
- COne (the Milky Way)
- DMillions
2.What is the name of the galaxy that contains our solar system?
Easy
- AMilky Way
- BAndromeda
- CSolar System Galaxy
- DBig Bang Galaxy
3.Approximately how long ago did the Big Bang occur?
Easy
- A13.8 billion years ago
- B5000 years ago
- C4.5 billion years ago
- D2.5 million years ago
4.What is the speed of light?
Easy
- A300,000,000 m/s
- B300,000 m/s
- C3,000,000 m/s
- D30,000,000 m/s
5.A light year is the distance light travels in one year. Which of the following is the correct value of one light year in metres?
Medium
- A9.5 × 10¹⁵ m
- B9.5 × 10¹² m
- C9.5 × 10¹⁸ m
- D9.5 × 10⁹ m
6.The Andromeda galaxy is 2.5 million light years away. What does this distance mean?
Medium
- ALight from Andromeda takes 2.5 million years to reach us
- BAndromeda is 2.5 million metres away
- CLight from Andromeda takes 2.5 million seconds to reach us
- DAndromeda is 2.5 million times the size of the Milky Way
7.What is at the centre of the Milky Way galaxy?
Medium
- AA black hole
- BA neutron star
- CA white dwarf
- DThe Sun
8.What is a nebula?
Medium
- AA cloud of dust and gas (mostly hydrogen)
- BAn explosion of a star
- CA small, hot star
- DThe centre of a galaxy

More questions

9.Which of the following is the correct sequence for the life cycle of a star similar to our Sun?
Hard
- ANebula → main sequence star → red giant → white dwarf → black dwarf
- BNebula → main sequence star → red supergiant → supernova → black hole
- CNebula → red giant → main sequence star → white dwarf → black dwarf
- DMain sequence star → nebula → red giant → white dwarf → black dwarf
10.What is formed from the explosion (supernova) of a very massive star?
Hard
- AA black hole
- BA neutron star
- CA white dwarf
- DA black dwarf
11.A red supergiant explodes in a supernova. Which object is left behind if the original star was not the most massive?
Hard
- AA neutron star
- BA black hole
- CA white dwarf
- DA black dwarf
12.Which of the following statements about galaxies is correct?
Hard
- AA galaxy contains billions of stars
- BA galaxy contains around 1000 stars
- CThe universe contains one galaxy
- DA galaxy is larger than the universe
13.Proxima Centauri is 4.2 light years away. Given that one light year is 9.5 × 10¹⁵ m, what is the distance to Proxima Centauri in metres?
Medium
- A3.99 × 10¹⁶ m
- B3.99 × 10¹⁵ m
- C9.5 × 10¹⁵ m
- D4.2 × 10¹⁵ m
14.Which of the following is the correct order of size from smallest to largest?
Easy
- ASolar system, galaxy, universe
- BGalaxy, solar system, universe
- CUniverse, galaxy, solar system
- DSolar system, universe, galaxy
15.Light from the Andromeda galaxy takes 2.5 million years to reach Earth. How far away is the Andromeda galaxy?
Medium
- A2.5 million light years
- B2.5 million metres
- C2.5 × 10⁶ km
- D2.5 × 10⁶ AU
16.A star has a mass 20 times that of the Sun. At the end of its life, it explodes in a supernova. What is most likely to remain after the supernova?
Hard
- AA black hole
- BA neutron star
- CA white dwarf
- DA black dwarf
17.What is the name of the explosion that occurs at the end of a red supergiant's life?
Easy
- ASupernova
- BRed giant
- CNebula
- DBig Bang
18.A student says: 'The universe was formed about 5000 years ago.' Is this statement true or false?
Medium
- AFalse, the universe formed 13.8 billion years ago
- BTrue
- CFalse, the universe formed 4.6 billion years ago
- DFalse, the universe formed 13.8 million years ago
19.The speed of light is 300 000 000 m/s. How far does light travel in one year? (1 year = 365 days, 1 day = 86400 s)
Hard
- A9.5 × 10¹⁵ m
- B3.0 × 10⁸ m
- C9.5 × 10¹² m
- D3.0 × 10¹⁵ m
20.The table shows the distances of some stars from Earth. Which star is the closest?
Medium
- AStar A: 4.2 light years
- BStar B: 6.0 light years
- CStar C: 8.6 light years
- DStar D: 10.5 light years
21.A star similar to the Sun runs out of hydrogen. It expands to become a red giant. What is the next stage in its life cycle?
Hard
- AWhite dwarf
- BSupernova
- CBlack dwarf
- DRed supergiant
22.Which of the following is the correct sequence in the formation of a main sequence star?
Medium
- ANebula → gravitational collapse → main sequence star
- BMain sequence star → nebula → gravitational collapse
- CGravitational collapse → nebula → main sequence star
- DNebula → main sequence star → gravitational collapse
23.A red supergiant explodes in a supernova. If the original star was not the most massive, what object is left behind?
Hard
- ANeutron star
- BBlack hole
- CWhite dwarf
- DBlack dwarf
24.A student uses a telescope to observe a distant galaxy. The light from the galaxy is found to be redshifted. What does the redshift of the light indicate about the galaxy?
Medium
- AThe galaxy is moving towards Earth.
- BThe galaxy is moving away from Earth.
- CThe galaxy is stationary relative to Earth.
- DThe galaxy is moving sideways relative to Earth.
25.A scientist measures the distance to a star using parallax. The star has a parallax angle of 0.1 arcseconds. Which of the following is the distance to the star?
Medium
- A1 parsec
- B10 parsecs
- C100 parsecs
- D0.1 parsecs
26.An astronomer observes a Type Ia supernova in a distant galaxy. The supernova has an apparent magnitude of 15. Knowing that Type Ia supernovae have a standard absolute magnitude of -19.3, what is the approximate distance to the galaxy? (Use the distance modulus formula: m - M = 5 log10(d) - 5, where d is in parsecs)
Hard
- A10 million parsecs
- B100 million parsecs
- C1 billion parsecs
- D10 billion parsecs
27.Which of the following is the correct definition of a light year?
Easy
- AThe time it takes light to travel from the Sun to Earth
- BThe distance light travels in one year
- CThe time it takes for light to travel one astronomical unit
- DThe distance from Earth to the nearest star
28.A star has a mass 10 times that of the Sun. At the end of its life, it explodes in a supernova. What is most likely to remain after the supernova?
Medium
- AA white dwarf
- BA neutron star
- CA black hole
- DA black dwarf
29.The Hubble constant H0 is approximately 70 km/s/Mpc. A galaxy is observed to have a recessional velocity of 7000 km/s. What is the approximate distance to the galaxy?
Hard
- A10 Mpc
- B100 Mpc
- C1000 Mpc
- D10,000 Mpc
30.Which of the following lists the stages in the life cycle of a star with a mass similar to the Sun in the correct order?
Medium
- ANebula → main sequence → red giant → white dwarf → black dwarf
- BNebula → main sequence → red supergiant → supernova → neutron star
- CNebula → main sequence → red giant → supernova → black hole
- DNebula → red giant → main sequence → white dwarf → black dwarf
31.A student uses a spectrophotometer to measure the spectrum of a star. The star's spectrum shows strong absorption lines of hydrogen. Which of the following can be determined from the position of these lines?
Hard
- AThe temperature of the star
- BThe chemical composition of the star
- CThe radial velocity of the star
- DAll of the above
32.A distant galaxy is observed to have a redshift z = 0.1. What does this redshift imply about the galaxy?
Medium
- AThe galaxy is moving towards us at 10% of the speed of light
- BThe galaxy is moving away from us at 10% of the speed of light
- CThe galaxy is stationary
- DThe galaxy is 10 million light years away
33.Which of the following is the correct order of magnitude for the number of stars in a typical galaxy?
Easy
- AThousands
- BMillions
- CBillions
- DTrillions
34.A student investigates the relationship between the distance of a galaxy and its recessional velocity. The student plots a graph of velocity against distance. What shape should the graph have?
Hard
- AA horizontal line
- BA curve that flattens off
- CA straight line through the origin
- DA straight line with a positive y-intercept
35.The universe contains billions of galaxies. Which of the following statements about galaxies is correct?
Easy
- AA galaxy contains billions of stars.
- BA galaxy contains around 1000 stars.
- CA galaxy is bigger than the universe.
- DThe universe contains only one galaxy.
36.Which of the following is the correct description of a nebula?
Easy
- AA cloud of dust and gas (mostly hydrogen)
- BA solid ball of rock
- CA large planet made of gas
- DA group of stars
37.A main sequence star runs out of hydrogen and expands. Which of the following correctly describes what happens next for a star similar in size to our Sun?
Medium
- AIt becomes a red giant, then a white dwarf, then a black dwarf.
- BIt becomes a red supergiant, then explodes in a supernova.
- CIt becomes a white dwarf directly.
- DIt becomes a black hole.
38.Which of the following is the correct sequence for the life cycle of a very massive star (much bigger than the Sun)?
Medium
- ANebula → main sequence star → red supergiant → supernova → black hole or neutron star
- BNebula → main sequence star → red giant → white dwarf → black dwarf
- CNebula → red supergiant → main sequence star → supernova → black hole
- DMain sequence star → nebula → red supergiant → supernova → neutron star
39.Which of the following statements about the universe is true?
Easy
- AThe universe was formed about 13.8 billion years ago in the Big Bang.
- BThe universe was formed about 5000 years ago.
- CThe universe is the same age as the Earth.
- DThe universe has always existed.
40.The Andromeda galaxy is 2.5 million light years away from Earth. If the speed of light is 300000000 m/s and one year is 365 days, what is the distance to the Andromeda galaxy in metres?
Medium
- A2.4 × 10²² m
- B2.4 × 10¹⁹ m
- C7.5 × 10¹⁴ m
- D9.5 × 10¹⁵ m

Revision notes

## Beyond the Solar System - The universe contains billions of galaxies. Our solar system is part of the **Milky Way** galaxy. - The universe formed **13.8 billion years ago** in the **Big Bang**. - Distances to galaxies are measured in **light years**. - Speed of light = **300,000,000 m/s**. - 1 light year = distance light travels in one year = **9.5 × 10¹⁵ m**. - Example: Andromeda galaxy is **2.5 million light years** away. - At the centre of the Milky Way is a **black hole**. ### Star Life Cycle 1. **Nebula**: cloud of dust and gas (mostly hydrogen). 2. **Main sequence star**: gravity pulls nebula together; pressure and friction raise temperature. 3. When hydrogen runs out: - Stars like the Sun become **red giants** → **white dwarf** → **black dwarf**. - Much bigger stars become **red supergiants** → **supernova** → **neutron star** (if less massive) or **black hole** (if most massive).

Galaxy: A huge collection of billions of stars.
Universe: All of space and everything in it, containing billions of galaxies.
Milky Way: The galaxy that contains our solar system.
Light year: The distance light travels in one year, equal to 9.5 × 10¹⁵ m.
Big Bang: The event that formed the universe 13.8 billion years ago.
Black hole: An object formed from the death of a very massive star, with gravity so strong that nothing can escape.
Nebula: A cloud of dust and gas (mostly hydrogen) where stars are born.
Main sequence star: A stable star formed from a nebula, like our Sun.
Red giant: A star similar to the Sun that expands after running out of hydrogen.
Red supergiant: A star much bigger than the Sun that expands after running out of hydrogen.
White dwarf: The hot, small core left behind after a red giant sheds its outer layers.
Black dwarf: A cooled white dwarf that no longer emits light.
Supernova: The dramatic explosion of a red supergiant.
Neutron star: A dense object left after a supernova of a less massive star.

Flashcards

What is a galaxy?

A galaxy contains billions of stars. The universe contains billions of different galaxies.

What is the name of our galaxy?

Our solar system is part of the Milky Way galaxy.

How old is the universe?

The universe was formed 13.8 billion years ago in the Big Bang.

How do we know the universe began with the Big Bang?

We know this by looking at the light emitted by distant galaxies.

What is a light year?

A light year is the distance travelled by light in one year, equal to 9.5 × 10¹⁵ m.

What is the speed of light?

The speed of light is 300,000,000 m/s.

How far away is the Andromeda galaxy?

The Andromeda galaxy is 2.5 million light years away.

What is at the centre of the Milky Way galaxy?

At the centre of the Milky Way galaxy is a black hole.

How is a black hole formed?

A black hole is formed from the death of a very massive star.

What is a nebula?

A nebula is a cloud of dust and gas (mostly hydrogen).

How is a main sequence star formed?

Gravitational attraction pulls dust and gas in a nebula together; pressure and friction increase temperature, forming a main sequence star.

What happens when a star runs out of hydrogen?

When stars run out of hydrogen, they expand.

What does a star similar in size to our Sun become after running out of hydrogen?

It becomes a red giant.

What does a star much bigger than our Sun become after running out of hydrogen?

It becomes a red supergiant.

What is the next stage after a red giant?

A red giant leaves behind a white dwarf, which then cools to form a black dwarf.

What is a supernova?

A supernova is the dramatic explosion of a red supergiant.

What remains after a supernova from the biggest stars?

The biggest stars leave behind a black hole.

What remains after a supernova from less large stars?

Less large stars leave behind a neutron star.

True or false: A galaxy contains around 1000 stars.

False. A galaxy contains billions of stars.

True or false: The universe contains billions of galaxies.

True.

True or false: A galaxy is bigger than the universe.

False. The universe is bigger; it contains billions of galaxies.

True or false: The universe was formed around 5000 years ago.

False. The universe was formed 13.8 billion years ago.

True or false: The speed of light is 300,000,000 m/s.

True.

Proxima Centauri is 4.2 light years away. Calculate this distance in metres (1 light year = 9.5 × 10¹⁵ m).

4.2 × 9.5 × 10¹⁵ = 3.99 × 10¹⁶ m.

Unlock all 40 questions, flashcards & more

Create a free account to see every question, the slides, flashcards and revision notes for this topic.

Past papers

Past-paper practice for this topic is coming soon.

Coming soon