Unit C - The Study Of The Universe

Question 1

Galaxy

Answer 1

A collection of hundreds of billions of stars held together by gravity

Question 2

Universe

Answer 2

The term used to refer to everything that physically exists: the entirety of space and time, and all forms of energy

Question 3

Celestial objects

Answer 3

Objects we can see in the sky e.g. the Sun, the Moon, Earth

Question 4

Astronomy

Answer 4

The study of the universe and and the objects in it

Question 5

The Solar system

Answer 5

Made up of the Sun, the 4 rocky inner planets, the 4 gas giant planets and other objects held my hw suns gravity such as asteroids, comets and moons

Question 6

Star

Answer 6

A hot ball of plasma, an electrically charged gas, that shines because nuclear fusion is taking place at its core

Question 7

Nuclear fusion

Answer 7

The process in which the nuclei of atoms fuse together and form larger atoms

Question 8

Astronomical Unit (AU)

Answer 8

The average distance between the Suns and the Earth, about 150 million km

Question 9

Light Year (ly)

Answer 9

The distance a beam of light can travel through space in 1 year, 63 000 AU or 9000 billion km

Question 10

Asteroid Belt

Answer 10

A region of rocky debris that forms a ring all the way around the Sun at a distance of about 3 AU

Question 11

Binary System

Answer 11

A system with two stars, more than half of the star systems have two or more stars

Question 12

Supernova

Answer 12

The explosion of a star where the outer layers of the star are pulled into the core by gravity. As the outer material crashed into the inner core, the temperature and pressure increase until the star explodes

Question 13

Nebula

Answer 13

A large cloud of dust and gas. Also called a star nursery, because stars develop from the dust and gas.

Question 14

The Milky Way

Answer 14

The galaxy inside which is our solar system. It’s a spiral galaxy and 100 000 ly across and about 2000 ly think at its widest point near the core.

Question 15

Black hole

Answer 15

A region of space where gravity is so strong that nothing, not even light can escape.

Question 16

Dark Matter

Answer 16

Matter in the universe that is invisible because it doesn’t interact with light or any other kind of radiation.

Question 17

Galaxy Shapes

Answer 17

Spiral, Barred Spiral, Elliptical, Irregular

Question 18

Visible light spectrum

Answer 18

The rainbow band of colours into which white light separates when it passes through a prism.

Question 19

Big Bang Theory

Answer 19

The universe formed when an infinitely dense point suddenly and rapidly expanded in a single moment.
George Gamow and Ralph Alpher

Question 20

When did the universe form?

Answer 20

13.7 billion years ago

Question 21

Electromagnetic radiation

Answer 21

A form of energy emitted and exhibited by charged particles that travels in waves.

Question 22

The electromagnetic spectrum from long to short waves

Answer 22

Radio, microwave, infrared, visible, ultraviolet, X-ray, gamma ray

Question 23

Spectroscope

Answer 23

An optical instrument that separates light into spectral colours.

Question 24

Spectral lines

Answer 24

A series of dark lines that appear across a stars band of colour, as each gas that makes up a star absorbs some of the light energy.

Question 25

Spectral shifting

Answer 25

The change in position of spectral lines to the left or the right of where they normally are in the spectrum of a light source that is not moving.

Question 26

Cosmic Background Radiation

Answer 26

Microwave energy left over from the massive and split- second expansion of the universe from a single point some 13.7 billion years ago.

Question 27

Constellation

Answer 27

A group of stars that, from Earth, resemble a recognizable form.

Question 28

Asterisms

Answer 28

Smaller recognizable star patterns within a larger constellation.

Question 29

Astronomical phenomenon

Answer 29

Any observable occurrence relating to astronomy.

Question 30

Formation of a star

Answer 30

Inside a collapsing nebula triggered by a disturbance such as the gravitational attraction of a nearby star or a shockwave from an exploding star.

Question 31

Protostar

Answer 31

A star in its first stage of formation.

Question 32

Hertzsprung - Russell Diagram

Answer 32

Plotted data of stars and are arranged by

• colour
• luminosity
• surface temperature

Question 33

Comet

Answer 33

A celestial object made of ice and dust.

Question 34

Meteoroids

Answer 34

Small pieces of rock and metal that travel throughout the solar system with no fixed path.

Question 35

Meteor

Answer 35

A meteoroid that begins to burn up as a result of friction upon entering the Earths atmosphere.

Question 36

Rotation

Answer 36

Earths rotation takes almost 24 h with it moving at 1670 km/h and tiled at an angle of 23.5 degrees.

Question 37

Solar eclipse

Answer 37

Occurs when the moon blocks the suns light to viewers on earth. The moon lie directly between the earth and the sun making it seem as though the sun has disappeared.

Question 38

Lunar eclipse

Answer 38

Occurs when the earth blocks out the suns light shining on the moon making the moon disappear fully or partially for a moment.

Question 39

Equinox

Answer 39

A day when the hours of daylight and the hours of night are of equal length.

Question 40

Orbital radius

Answer 40

A planets distance from the Sun.

Question 41

4 types of spacecraft in use

Answer 41

-Rockets
Lift small capsules containing crew, equipment or satellites
-Space shuttles
Transport personnel and equipment to orbiting spacecraft
-Space stations
Orbiting spacecraft that have living quarters, work areas, and everything needed to allow people to live and work in space for extended periods
-Space probes
Carry instruments for robotic exploration of space

Question 42

International space station

Answer 42

Assembled in stages since 1998 and orbits 400 km above Earth. Has the Canadaarm2

Question 43

Artificial satellite

Answer 43

A device placed in orbit around Earth or another celestial object.

Question 44

Geostationary orbit

Answer 44

When a satellite orbits the Earth at the same rate as the Earth rotates.