Lecture 1

Question 1

What is geospace?

Answer 1

region around the earth with size 200Re

Question 2

What is the Ionosphere?

Answer 2

50-1000km layer of electrons and ionized atoms within the meso and thermosphere

Question 3

What scale are Geomagnetic storms classified by and what is the worst

Answer 3

G scale- worst is G5

Question 4

What are geomagentic storms caused by?

Answer 4

CME’s/ Solar wind (protons, electrons and alpha particles)

Question 5

What are the effects of Geomagnetic storms (G.A.P)

Answer 5

Effect power grids, GPS and cause auroras

Question 6

How long does it take a geomagnetic storm to reach us

Answer 6

1-3 days

Question 7

What is a solar radiation storms made of?

Answer 7

High energy particles- mostly protons, some electrons

Question 8

What does a solar radiation storm affect? (AAS)

Answer 8

Astronauts, aircraft and satellites

Question 9

How long does it take a solar radiation storm to reach us?

Answer 9

Minutes, hours

Question 10

What is the scale used for solar radiation storms and what’s the highest measurement?

Answer 10

S5 S scale

Question 11

What are radio blackouts caused by

Answer 11

Solar flares( x rays)

Question 12

What do Radio blackouts effect?

Answer 12

Radio communications

Question 13

How quickly do radio blackouts occur?

Answer 13

minutes

Question 14

What scale are radio blackouts measures on and whats the highest measurement

Answer 14

R5 R scale

Question 15

What space weather is there that comes from out of our solar system

Answer 15

Cosmic rays

Question 16

What are cosmic rays caused by?

Answer 16

Supernovas or magnetars

Question 17

What are cosmic rays?

Answer 17

High energy particles accelerated by energetic astrophysical events

Question 18

Does plasma have more or less energy than a gas

Answer 18

more

Question 19

Is plasma electrically neutral

Answer 19

Yes

Question 20

Is plasma an insulator

Answer 20

No it is a conductor

Question 21

Does a plasma exhibit wave motions

Answer 21

yes

Question 22

Does a plasma react as individual particles to electric and magentic fields?

Answer 22

No it acts collectively

Question 23

What is the Debye Length?

Answer 23

The distance at which a particle influences the surronding plasma

Question 24

Plasma criteria 1- equation and exaplain

Answer 24

DL«_space;L
Where L is the scale of the system
The system has to be much bigger then that so that the system can be quasi stable

Question 25

Plasma criteria 2 eq and explain

Answer 25

4pi/3*n*DL^3 >>1 The debye volume needs to be big enough so it does electric shielding correctly

Question 26

Plasma criteria 3- eq and explanation

Answer 26

When matter is not fully ionised- needs to not affect the system that much. collisions between charged and neutral particles needs to be small enough so that non ionised effects are not dominant. tn is time between collisions wpe*t(n) >>1

Question 27

what is bulk velocity?

Answer 27

the average velocity

Question 28

In a plasma what are the two ways to charactrise their movement

Answer 28

bulk motion- the average flow Thermal motion- random motion around that average flow

Question 29

How can you work out the thermal kinetic energy

Answer 29

1/2 * m *( v-vbulk)^2 as thermal

Question 30

What does temperature represent in space weather

Answer 30

The energy it has

Question 31

if temperature is given in EV what can you assume

Answer 31

that it equals to kbT and T1ev=1.1^104K

Question 32

Of electric and magnetic field which one changes a particles kinetic energy

Answer 32

electric

Question 33

Why does plasma gyrate?

Answer 33

Because it is ionised particles and therefore they experience the lorenz force- which shows they gyrate

Question 34

What is the pitch angle? and what does it determine

Answer 34

the angle between its velocity and magnetic field direction- how much of the motion is trapped vs free It determines whether the particle is trapped, reflected or lost in space plasmas

Question 35

Why does bounce motion happen?

Answer 35

Becuase earths magnetic field is stronger near the poles, so as the particle moves along the field lines it gets reflected near the poles

Question 36

Why does drift motion happen and what does it cause?

Answer 36

From non-uniform field and curvature puts them sideways- drift direction depends on charge it causes ring currents

Question 37

What do magntars emit

Answer 37

Gamma radiation- similar to flares on the sun

Question 38

Increasing in suns magnetic field does what to cosmic rays

Answer 38

Decreases them cause more are deflected

Question 39

Two things for guiding centre approximation to be true

Answer 39

radius smaller, gyration period smaller then actual period

Question 40

what is spatial scale of plasma in terms of wave length

Answer 40

half the wave length

Question 41

What does being outside of the magnetopuase do to a spacecraft

Answer 41

won't be affected by particles trapped in electron belt but wont be sheilded from energetic particles and waves

Question 42

What depends on power systems?

Answer 42

Water supply, fuel supply, communication, banking and finance