Earth and Space

Question 1

Astronomy

Answer 1

The study of the universe and everything in it

Question 2

Geocentric

Answer 2

A theory of the structure of the solar system in which the earth was thought to be at the centre

Question 3

Heliocentric

Answer 3

A theory of the structure of the solar system where the Sun is at the centre.

Question 4

Universe

Answer 4

Everything that exists, including planets, stars, galaxies and all forms of matter and energy.

Question 5

Big Bang

Answer 5

Most scientists believe that the universe began with an explosion - the Big Bang - about 14 billion years ago.

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. When they meet they destroy each other and are converted into pure energy.

Question 8

Hypothesis

Answer 8

Collection of ideas that seem to explain what is observed

>predictions that can be tested

Question 9

Models

Answer 9

Describes reality based on Hypothesis that have withstood observational and experimental tests >explains with mathematics properties and behaviors of some object or phenomenon

Question 10

Theory

Answer 10

Series of well-tested hypothesis that together from a self-consistent and accurate description of nature >capable of making predictions that can be tested and verified by anyone

Question 11

Laws

Answer 11

Proven theories that have stood the test of time and have broad applicability

Question 12

Constellation

Answer 12

Some of these stars seem to be grouped forming images in the sky
There are 88 constellation covering the entire sky

Question 13

Ecliptic plane

Answer 13

Plane of Earth’s orbit around the sun

The orbit is not quite a circle (eclipse) squashed circle

Question 14

Antimatter

Answer 14

matter consisting of elementary particles which are the antiparticles of those making up normal matter.

Question 15

Solar system

Answer 15

Our solar system includes the Sun and all the objects that orbit around it due to its gravity, including the Earth.

Question 16

Celestial body

Answer 16

Any natural body outside of the Earth’s atmosphere. There are various celestial bodies, including planets, stars, moons, comets and asteroids.

Question 17

Planet

Answer 17

An object that is in orbit around a star, has sufficient mass to assume a nearly round shape, and has become gravitationally dominant. This means that it can clear the space debris in its orbit

Question 18

Moon

Answer 18

A natural satellite that orbits a planet

Question 19

Star

Answer 19

A ball of heat radiating gas that is held together by gravity. Stars contain mostly hydrogen as well as helium and smaller amounts of other elements.

Question 20

Sun

Answer 20

The star that lights and heats our planet. The Sun is powered by a fusion reaction at its core.

Question 21

Light-year

Answer 21

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 22

Asteroid

Answer 22

Lumps of rock that orbit the Sun but are too small to be classified as planets. There are three types of asteroids, divided based on what they are made up of:
C-type asteroids are made up of carbon compounds;
S-type asteroids are made up of stony material;
M-type asteroids are mostly made of metals, such as iron.

Question 23

Comet

Answer 23

A celestial body that orbits the Sun, made up of a nucleus, a coma and one or more tails. The nucleus of a comet is made up of dust and ice. The coma (a fuzzy outline or atmosphere caused by the Sun’s radiation) is made up of carbon dioxide, dust and water vapour. The tail is made up of gas and dust produced by the nucleus.

Question 24

Terrestrial planet

Answer 24

Planets made up of rock. In our solar system, the terrestrial planets are the four inner planets.

Question 25

Gas giant

Answer 25

The outer planets in our solar system are called gas giants because they are mainly made of gases hydrogen and helium.

Question 26

Gravity

Answer 26

A non-contact force of attraction between objects. There is a gravitational pull between all masses.

Question 27

Force field

Answer 27

A region in space where an object feels a force.