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Flashcards in Space Deck (37):
1

What are the stages of a low mass star's life cycle?

Nebula
Protostar
Main Sequence Star
Red Giant
White Dwarf
Black Dwarf

2

What are the stages of a high mass star's life cycle?

Nebula
Protostar
Main Sequence Star
Red Super Giant
Supernova
Neutron Star / Black Hole

3

What determines if a Supernova turns into a black hole?

When it explodes, if the neutron star that is formed is massive enough, it creates a black hole

4

What is a nebula?

A cloud of dust and gas

5

How is a protostar formed?

Gravity pulls the nebula together

6

What causes the hydrogen nuclei to form helium nuclei?

An increase in temperature

7

In what process does hydrogen nuclei form helium nuclei?

Nuclear fusion

8

How does a main sequence star stay maintained?

The outward pressure, which is trying to expand the star, balances the force of gravity

9

How long does a main sequence star last for?

Several billion years

10

Why does the star become red in the red [super] giant stage?

The surface cools

11

Up to which element begins to get created in the core of the star in the red [super] giant stage?

Iron

12

What is a white dwarf?

The core of a low mass star after it becomes unstable and ejects its outer layer of dust and gas

13

True or false?

Pluto is a dwarf planet.

True

14

What is a black dwarf?

A white dwarf that has stopped emitting a significant amount of energy

15

What is a supernova?

The explosion that occurs from the collision caused by gravity pulling in all the elements heavier than iron that are being created

16

What is a neutron star?

The very dense core left from an exploding supernova

17

How do you identify whether a star is high mass or low mass?

Stars the same size or smaller than our sun are low mass, any others are high mass

18

Why is gravity able to pull in elements heavier than iron in a supernova?

Elements heavier than iron emit a lesser outward pressure so the forces are no longer balanced

19

How many other planets orbit our sun?

8 (or 9 including Pluto)

20

Define the term solar system.

Our sun and all the stuff that orbits around it

21

What order are the planets in moving away from the sun?

Mercury
Venus
Earth
Mars
Jupiter
Saturn
Uranus
Neptune
[Pluto]

22

What does the phrase "cleared their neighbourhood" in terms of planets mean?

The gravity is strong enough to have pulled in any nearby objects apart from their satellites?

23

Give an example of a natural satellite.

Moons

24

What is a satellite?

An object that orbits a second, more massive object

25

What galaxy are we in?

The Milky Way

26

How many stars are in the milky way?

Billions

27

What shape are the orbits that the planets make around our sun?

Almost circular

28

How are circular orbits created?

The force of gravity that is pulling the object towards the middle is being counteracted by the perpendicular constant change in velocity of the planet

29

True or false?

The radius of an orbit will change if the speed of the orbiting object changes.

True

30

What is a red-shift?

Light from space whose wavelengths appear longer than they should be; they have shifted towards the red end of the spectrum

31

What does red-shift prove?

The universe is expanding

32

What does the big bang theory suggest?

All the matter in the universe used to be compressed in a very small space so was very dense and very hot. There was an explosion and the space started expanding (and still is expanding)

33

What is dark matter?

The name given to an unknown substance which holds galaxies together but does not emit any electromagnetic radiation

34

What part of its life cycle is our sun currently in?

Main sequence

35

At what stage in a stars life cycle do elements heavier than iron get created?

Supernova

36

True or false?

The sun will eventually turn into a black hole.

False
It is a low mass star

37

True or false?

An object in a stable orbit is constantly changing speed.

False
It is constantly changing velocity