Astronomy Test 1

Front 1

Light Year

Back 1

A light year is how far light travels in a year. This is approx. 6 trillion miles.

Front 2

AU

Back 2

An Astronomical Unit, equivilant to 93 million miles.

Front 3

Rotation

Back 3

Object spins on it's axis

Front 4

Orbit (revolution)

Back 4

The orbital motion of on eobject around another due to gravity.

Front 5

Tilt

Back 5

causes seasona an dis 23.5 for earth

Front 6

Celestial Sphere

Back 6

Imaginary globe around earth

Front 7

North and South Celestial Poles

Back 7

Points above our geographic poles.

Front 8

Where is Polaris?

Back 8

North Pole

Front 9

Celestial equator

Back 9

Earths equator projected out and drawn on a celestial sphere

Front 10

Zenith

Back 10

Point directly overhead for an observer. Has an altitude of 90dgs

Front 11

Meridian

Back 11

Line drawn from north to south thru zenith

Front 12

Local sky

Back 12

the part of the celestial sphere an observer sees

Front 13

Altitude

Back 13

how far above horizon an object is

Front 14

Direction

Back 14

stars from north and gives direction from there

Front 15

Circumpolar

Back 15

part of sky that never sets, depends on latitude

Front 16

Summer Solsitce

Back 16

Summer: June 21st - Northern Hemisphere is tipped most directly towards the sun and receives the most sun light.

Front 17

Winter Solstice

Back 17

Winter: December 21st - Northern Hemisphere is receives the least direct sunlight.

Front 18

Spring Solstice

Back 18

March 21st - Northen Hemisphere goes from being tipped slightley away from the sun to being tipped slightly towards the sun.

Front 19

Fall Solstice

Back 19

September 22nd - Northern Hemisphere first starts to be tipped away from the sun.

Front 20

Precession

Back 20

26,000 years for earth to wobble, changes the direction in which the axis points in space which changes the constellations that we see during each equinox.

Front 21

Umbra

Back 21

full shadow

Front 22

Penumbra

Back 22

partial shadow

Front 23

Retrograde motion

Back 23

backward motion of planets as we pass them

Front 24

Parallax

Back 24

best way to measuer distance

Front 25

What is stonehenge?

Back 25

Ancient calandar in England

Front 26

Geocentric

Back 26

An earth centered system.

Front 27

Ptolemaic model

Back 27

used earth at center of epicycles

Front 28

Deferent

Back 28

large circle

Front 29

Epicycle

Back 29

small circle, circle on circles

Front 30

Copernicus

Back 30

put sun at center, heliocentric

Front 31

Tycho Brache

Back 31

made observations used by Kepler of planetary motion

Front 32

Kepler

Back 32

uses Brahe data and provided heliocentric and three laws

Front 33

Kepler's 1st Law

Back 33

The orbit of each planet about the Sun is an ellipse with the Sun at one focus.

Front 34

Kepler's 2nd Law

Back 34

As a planet moves around its orbit, an imaginary line connecting it to the Sun sweeps out equal areas in equal times.

Front 35

Kepler's 3rd Law

Back 35

more distant planets orbit the sun at slower average speeds.

Front 36

Galileo

Back 36

Used telescope and was physical scientists

Front 37

What did Galileo discover?

Back 37

He discovered that the earth is moving along with everything on earth (using Newton's first law of motion). He also discovered the the "heavens" could infact change by using a telescope to observe the moon and sun. He also discovered the stellar parallax.

Front 38

Paradigm

Back 38

New Idea

Front 39

Scientific Method

Back 39

Make observations
Ask a Qustion

Suggest a hypothesis
Make a prediciton
Perform Test

Front 40

Hypothesis

Back 40

A proposal

Front 41

Theory

Back 41

Data that proves hypothesis

Front 42

Velcoity =

Back 42

Distance/Time

Front 43

Acceleration =

Back 43

Velocity/Time

Front 44

Momentum =

Back 44

Mass x Velocity

Front 45

Force =

Back 45

Mass x Acceleration

Front 46

Mass

Back 46

Mass is the amount of matter

Front 47

Weight

Back 47

Weight is gravity acting on mass

Front 48

Weightless-free fall

Back 48

You cancel effects of gravity

Front 49

Newtons three Laws

Back 49

A body in motion stays in motion (inertia)

Force equals mass times acceleration
For every action there is an equal and opposite reaction.

Front 50

Angular Momentum

Back 50

Amount of spin

Front 51

Kinetic Energy

Back 51

Energy of motion

Front 52

Potential energy

Back 52

Energoy of position

Front 53

Radiative energy

Back 53

light

Front 54

Temperature

Back 54

Speed of molecules

Front 55

E=mc2

Back 55

energy equals mass times the speed of life squared

Front 56

Law of Gravity

Back 56

Fg = G(M1M2/D2) Force of gravitaional attraction is equal to the masses of two objects divided by the distance between their centers.

Front 57

Escape veloicty

Back 57

how fast you need to move to escape a particular body

Front 58

Tide Forces

Back 58

Pull of gravitry and it's effects

Front 59

Neap tides - diagram

Back 59

20% lower

Front 60

Spring tides - diagram

Back 60

20% higher