Space

Question 1

What is a light year?

Answer 1

The distance that light travels in 1 year (9.26 x 10^12)

Question 2

What is an astronomical unit?

Answer 2

The distance from the Earth to the sun (1.5 x 10^8)

Question 3

Which direction does the Earth rotate?

Answer 3

West to East

Question 4

What are the 4 reasons that Earth is so perfect for life?

Answer 4

1. Distance - not too hot, not too cold
2. Magnetic field (magnetosphere) - stops solar wind from stripping atmosphere
3. Tilt - heat is distributed regularly over Earth
4. Atmosphere - traps heat from sun to create new greenhouse effect

Question 5

How old is the milky way?

Answer 5

8-9 billion years

Question 6

How long did it take for H and He to form?

Answer 6

377 000 years (after temperature cooled)

Question 7

How hot was it, during the Big Bang?

Answer 7

10 billion K

Question 8

How old is the universe believed to be? How do we know?

Answer 8

12.7 billion years old, and we know the rate of expansion

Question 9

How do we know the universe is expanding?

Answer 9

1. Galaxies appear to be moving away from us (Doppler effect)
2. Remnant cosmic microwave background = radiation left over from the big bang, used to be gamma rays, now is microwave

Question 10

How can we tell the latitude?

Answer 10

Fist = 10 degrees
Telephone = 20
Three fingers = 5
Pinky = 1

Question 11

What are nebulas?

Answer 11

Star-forming clouds of dust (irregular grains or carbon & silicon) and gas

Question 12

What is a protoplanetary disk?

Answer 12

Disk of gas & planetismals, forms along equatorial region

Question 13

What is the nearest star forming region?

Answer 13

The Arion Nebula

Question 14

How was our solar system formed?

Answer 14

1. Gravity pulls clouds of dust t/g
2. H begin gathering, as they become more concentrated = protostar
3. Powered by nuclear energy, they push aside the dust of their cocoons
4. Surrounding these new stars are left over material
5. Gravity + rotation causes dust to form flat disks which will eventually form planets

Question 15

How are stars made?

Answer 15

• cloud of hydrogen gas
• balls of gas formed
• balls of gas expanded

Question 16

How do stars die?

Answer 16

• stars run out of hydrogen fuel
• star cools, shrinks, collapses under weight
• star crashes inward and explodes!
• supernova creates new worlds

Question 17

What is a lunar eclipse?

Answer 17

When the full moon passes into Earth’s shadow. You can see it anyway & it is safe to watch

Question 18

What is a solar eclipse?

Answer 18

When the shadow of the new moon falls on Earth’s surface. You must be in a specific place but not safe to watch

Question 19

Why don’t we have a lunar eclipse every full moon?

Answer 19

The orbit of the moon is tilted 5 degrees to Earth’s orbit about the sun. The full moon usually passes above or below Earth’s shadow

Question 20

On the equinoxes, all places on Earth experience equal hours because __________

Answer 20

During those dates, the earth is not tilted towards or away from the sun

Question 21

What is the oort cloud?

Answer 21

Sphere of small, icy debris at the farthest reaches of the sun’s gravitational pull

Question 22

How are tides caused?

Answer 22

By the difference between the force of gravity on 1 side of the Earth nearest the moon and the side farthest

Question 23

What are the 3 pieces of evidence supporting the solar nebula theory?

Answer 23

1. Cratered surfaces of moon +mercury (pounding of nebula?)
2. Planets revolve around sun in 1 direction (nebula spins in 1 direction)
3. LOTS of planets (planets are by-products of stars)

Question 24

What is the nuclear fusion process?

Answer 24

1. Nuclear fusion starts when star gets hot enough (you need it to be highly pressurized)
2. Hydrogen nuclei combine to form helium nuclei
3. Protostar begins to consume fuel (core heats up which increases pressure)
4. Pressure and gravity balance out, creating a star!
5. Star continues to fuse H and He, so core grows bigger and bigger

Question 25

What are sunspots?

Answer 25

Area of strong magnetic field on photosphere

Question 26

What are solar flares?

Answer 26

Complex groups of sunspots. Causes solar wind

Question 27

What is solar wind?

Answer 27

Explosively ejected streams of charged particles into space

Question 28

How is the Auroras an example of solar wind?

Answer 28

Auroras result when solar wind are carried past Earth’s magnetic field, generating electric currents that flow towards poles

Question 29

How are galaxies formed?

Answer 29

1. Bodies of gas, dust, and protostars collide
2. Begin rotating around center of mass
3. Rotation contracts cloud to form a disk

Question 30

Does a star’s apparent brightness depend on just it’s distance from Earth?

Answer 30

No, a star’s brightness also depends on it’s luminosity; a bright star is not necessarily closer to Earth.

Question 31

List 4 properties of stars

Answer 31

Brightness, colour, temperature, composition

Question 32

What is the fate of our Sun?

Answer 32

To become a red giant and explode in a supernova

Question 33

How are humans stardust?

Answer 33

Heavier elements released through supernova explosions are ejected throughout the universe; eventually showing up on stars, planets, and HuMaNs