P8.3 Beyond Earth

Question 1

Red-shift

Answer 1

Wavelength of light moving away from you increases and the frequency decreases
It shifts more towards the red side of the absorption spectrum

Question 2

Blue-shift

Answer 2

Opposite of red shift
When an object moves closer, the visible light moves to the blue end of the spectrum, as its wavelengths appear shorter

Question 3

When an object is moving faster than you

Answer 3

Bigger red-shift

Question 4

When an object is moving slower than you

Answer 4

Blue-shift

Question 5

Hubble’s constant or galaxy speed

Answer 5

1/10 × distance

Question 6

Universe’s age

Answer 6

1 / Hubble’s constant

Question 7

Cosmic microwave background radiation (CMBR)

Answer 7

Residual energy from the Big Bang. Very high energy radiation with high frequency stretched out over time until it became a microwave on the electromagnetic spectrum

Question 8

The Sun

Answer 8

The star at the centre of the Solar System

Question 9

Planets

Answer 9

Spherical objects orbiting the Sun due to gravity

Question 10

Moons

Answer 10

Objects orbiting planets

Question 11

Comets

Answer 11

Made of dust and ice
Orbit the Sun with long and thin orbits

Question 12

Minor planets

Answer 12

Anything orbiting the Sun other than planets or comets, i.e. asteroids, dwarf planets

Question 13

Inner planets

Answer 13

Mercury, Venus, Earth, Mars
Rocky planets
Have an atmosphere

Question 14

Outer planets

Answer 14

Jupiter, Saturn, Uranus, Neptune
First two = gas giants
Second two = ice giants
All have rings and lots of moons

Question 15

Asteroids

Answer 15

Rock fragments leftover from the creation of the Solar System
The asteroid belt is between Mars and Jupiter

Question 16

Star life cycle of a less massive star

Answer 16

Star birth from dust and gas (nebula) → nebula condenses into a protostar → nuclear fusion → main sequence star → hydrogen runs out and fusion starts again → red giant → white dwarf → cools down → black dwarf

Question 17

Life cycle of a more massive star

Answer 17

Star birth from dust and gas (nebula) → nebula condenses into a protostar → nuclear fusion → main sequence star → hydrogen runs out and fusion starts again → red super giant→ explodes → supernova → neutron star (if big)/black hole (really massive)

Question 18

Natural satellite

Answer 18

Non-man-made objects that orbit a planet
Example: the Moon

Question 19

Artificial satellite

Answer 19

Man-made objects that orbit a planet

They have two types of orbits:
- geostationary orbit
- low polar orbit

Question 20

Geostationary orbit

Answer 20

Takes 24hrs to complete one orbit.
Around 36,000 km above the Earth’s surface.
They remain fixed over the equator.
Used for communication and satellite television

Question 21

Low polar orbit

Answer 21

Takes around 2 hrs to complete one orbit.
Can reach up to 2,000 km above the Earth’s surface.
They orbit over the poles.
Used for weather, military, and Earth observation

Question 22

If an orbiting object speeds up…

Answer 22

it’ll fly away due to too much gravitational energy

Question 23

If an orbiting object slows down

Answer 23

it’ll accelerate and crash into the object it’s orbiting

Question 24

If an object emits more radiation than it absorbs…

Answer 24

Its temperature decreases

Question 25

If an object emits less radiation than it absorbs…

Answer 25

Its temperature increases

Question 26

If an object emits the same amount of radiation that it absorbs…

Answer 26

It stays at constant temperature

Question 27

The Earth’s contents (going outwards)

Answer 27

Solid inner core, liquid outer core, Mostly solid mantle (but it can flow), solid crust

Question 28

Seismic waves

Answer 28

Waves from an earthquake

Question 29

How do we use seismic waves

Answer 29

Measured on seismometers
Plotted on seismographs

Question 30

P-waves

Answer 30

Primary (seismic) wave
Arrives at the surface first in an earthquake
Longitudinal waves, can travel through solids and liquids

Question 31

S-waves

Answer 31

Secondary (seismic) wave
Arrives at the surface second in an earthquake
Transverse waves, can only travel through solids → core must be liquid then