Origins of The Universe

Question 1

Astronomy

Answer 1

The study of the universe and everything in it.

Question 2

Geocentric Model

Answer 2

The Sun, Moon, planets and stars all orbit the Earth which does not move.

Question 3

Heliocentric Model

Answer 3

Planets orbit the Sun instead of the Earth.

Question 4

Universe

Answer 4

Made up of everything that exists, including planets, stars, galaxies and all forms of matter and energy.

Question 5

Big Bang Theory

Answer 5

The idea that scientists use to explain how our universe was formed.

Question 6

Galaxy

Answer 6

A large group of stars, dust, gas and dark matter held together by gravity.

Question 7

Antimatter

Answer 7

The mirror image of matter. Every particle of matter has a corresponding particle of antimatter.

Question 8

Celestial Body

Answer 8

Any natural body outside of the Earth’s atmosphere.

Question 9

Moon

Answer 9

A natural satellite which orbits a planet.

Question 10

Star

Answer 10

A ball of heat-radiating gas that is hed together by gravity

Question 11

Nuclear Fusion

Answer 11

Involves two small nuclei joining together to form a larger nucleus.

Question 12

The Sun

Answer 12

The closest star to Earth.

Question 13

Light Year

Answer 13

The distance that light travels in one year. Light-years are often used in astronomy to describe the distance to faraway stars and galaxies.

Question 14

Asteroids

Answer 14

Lumps of rock that orbit the Sun.

Question 15

The Three Asteroid Types:

Answer 15

1. C-type asteroids are made up of carbon compounds.
2. S-type asteroids are made up of stony material.
3. M-type asteroids are mostly made up of metals, such as iron.

Question 16

Comet

Answer 16

A small lump of ice and dirt that orbits the Sun.

Question 17

The Three Parts of A Comet

Answer 17

1. The Nucleus: Made of dust and ice.
2. The Coma: A fuzzy outline or atmosphere caused by the Sun’s radiation, made up of carbon dioxide, dust and water vapour.
3. The Tail: Made up of gas and dust produced by the nucleus.

Question 18

Terrestrial Planets

Answer 18

The four inner planets are called terrestrial planets because they are made up of rock. They are Mercury, Venus, Earth and Mars.

Question 19

Gas Giants

Answer 19

The four outer planets are called gas giants because they are mainly made of gases hydrogen and helium. They are Jupiter, Saturn, Uranus and Neptune.

Question 20

Mercury

Answer 20

Small for a planet, roughly the same size as the Moon.
Has no atmosphere and is covered in craters.
The side of the planet facing the Sun is very hot (approximately 430 degrees celsius).

Question 21

Venus

Answer 21

Similar in size to Earth.
Covered in clouds of sulfuric acid and has an atmosphere made of carbon dioxide.
It is even hotter on Venus than on Mercury.

Question 22

Earth

Answer 22

Fifth largest planet.
Only planet with liquid water, oxygen and living things.
It is at the right distance from the Sun and has the right chemicals to support life.

Question 23

Mars

Answer 23

Iron oxide gives Mars its reddish colour.
Has a dusty, rocky surface, calm conditions and a thin atmosphere of carbon dioxide.
It is rocky, with mountains and valleys.

Question 24

Jupiter

Answer 24

The largest planet.
Has no solid surface and is mainly made of hydrogen and helium.
It has many moons, some of which have volcanoes.

Question 25

Saturn

Answer 25

The second largest planet.

It has an impressive system of rings which aren’t solid but made up of billions of tiny particles of ice.

Question 26

Uranus

Answer 26

Third largest planet.
Has an atmosphere of hydrogen and helium. It looks blue-green and has very faint rings.
Its axis is tilted so that it is lying on its side as it rotates the Sun.

Question 27

Neptune

Answer 27

Is four times the size of Earth.
It has strong winds and violent weather.
It is blue in colour due to a thick atmosphere of cold methane gas.

Question 28

Gravity

Answer 28

A non-contact force of attraction between objects.

Question 29

Three Things About Gravity

Answer 29

1. There is a gravitational pull between all masses.
2. Larger masses give a stronger pull.
3. The closer things are to each other, the greater the force of gravity between them.

Question 30

Force Field

Answer 30

A region in space where an object feels a force.

Question 31

Formula for Calculating Weight

Answer 31

Weight (N) = Mass (kg) x Gravity (N/kg)