Topic 4: Space

Question 1

Universe

Answer 1

Consists of many galaxies seperated by empty space

Question 2

Galaxy

Answer 2

A large cluster of stars (Milky Way/Andromeda)

Question 3

Star

Answer 3

A large ball of matter that is undergoing nuclear fusion and emitting light. The sun is a star

Question 4

Solar System

Answer 4

The sun + all the planets orbiting it

Question 5

Planet

Answer 5

Large ball of matter that orbits a star

Question 6

Exoplanet

Answer 6

A planet existing around another star, outside of our solar system

Question 7

Satellite

Answer 7

Body that orbits a planet. Moons are natural sateilltes whereas communication satellites are artificial

Question 8

Dwarf Planet

Answer 8

An object that orbits a star but it is not large enough to be a planet

Question 9

Challenge of space travel: The distance

Answer 9

Travelling long distances in space is very difficult + requires a very fast speed, while maintaining energy and fuel

Question 10

Solution for the distance in space

Answer 10

• Large distances can be travelled using ion drive, where a small unbalanced force allows a high velocity to be achieved over an extended period of time.
• Energy can be preserved + high velocites can be reached by ‘catapulting’ from a fast moving asteriod, moon or planet.

Question 11

Challenge of space travel: The energy supply

Answer 11

Sufficent energy is required to power life support system for space travel

Question 12

Solution for the energy supply in space

Answer 12

• Energy can be generated on a spacecraft using solar cells

Question 13

Frictionless Environment in space

Answer 13

Maneuvering spacecraft in their frictionless environments is a very demanding operation. There are no outside particles or surfaces that can be used to control speed and direction. The spacecraft has to control this from within.

Question 14

Risks in space travel (4)

Answer 14

• Exposure to radiation - can damage human cells
• Re-entry into the atmosphere can be extremely dangerous as they are exposed to varied and increased levels of radiation
• Fuel load on take off has a risk of ignition and explosion
• Pressure differential between the vacuum of space and the atmospheric pressure in the spacecraft poses a risk to the astronauts.

Question 15

Asteroid

Answer 15

A group of rocks in space that orbits the sun

Question 16

Lightyear

Answer 16

The distance that light travels in a year. This can be calculated using the equation: d=vt

Question 17

Big bang theory

Answer 17

A theory that states that all current and past matter in the universe came into existence at the same time.

Question 18

Big bang theory key points

Answer 18

• The universe is 13.8 billion years old
• The universe is still expanding at an increasing rate
• Expanded as a signularity from a hot, tiny and dense point

Question 19

What is white light made up of?

Answer 19

Range of colours

Question 20

How can white light be seperated?

Answer 20

With a glass prism to obtain a spectrum

Question 21

Continous spectrum

Answer 21

What would be seen from a source of white light

Question 22

Line emission spectrum

Answer 22

When elements are heated, they glow. If this light is passed through a prism, it produces this spectrum

Question 23

Absorption spectrum

Answer 23

When pure light is passed through an element in its gas form, this spectrum is produced

Question 24

All elements emit…

Answer 24

a unique light spectrum

Question 25

How can we see what elements different stars and planets contain?

Answer 25

Using spectroscopy and visualising line spectra

Question 26

Evidence for big bang theory

Answer 26

• Red shift (evidence that galaxies are moving away from us)
• Background microwave radiation
• Heat energy in deep space