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Flashcards in astronomy 2 Deck (40):
1

what is the difference between rotation and revolution

rotate-spin
revolution-motion around another object

2

what does earths rotation produce

night and day

3

how do we know earth rotates

Foucaults pendulum - earth rotates beneath it

4

what is earths orbit shape

elliptical

5

how do we know the earth revolves around the sun

parallax- shift in position of a nearby star

6

why do we see different constellations

because we revolve around the sun
see constellations that are opposite the sun

7

what are seasons caused by

earths revolution
earths tilt

8

what way is the earth tipped during summer and winter

toward the sun
away from the sun

9

what is precession

movement of earths axis
axis wobbles slowly over time

10

when is the sun highest and lowest in the sky

highest on the summer solstice
lowest on winter solstice

11

where does the sun rise and set on the equinoxes
the fall and winter the spring and summer

exactly in the east and west
sun rises SE and sets SW
rises NE and sets NW

12

what is the celestial equator

projection of earths equator in space
at the earths equator the celestial equator is directly overhead

13

what is the ecliptic

the path the sun travels in the sky
zodiacs located along the ecliptic

14

what is altitude

angle of the sun above the horizon
no direction on altitude

15

what is moon phase

the amount of the moon that is visible from the earth
waxing-revolving toward full
waning-revolving toward new

16

how long does it take for the moon to revolve around the earth

moon revolves around earth in 29 days- full moon to full moon

17

why does the moon rise and set

because the earth rotates

18

what is an eclipse

an eclipse is when an object in space passes into the shadow created by another object in space
umbra-total shadow
penumbra-partial shadow

19

types of lunar eclipses

total lunar eclipse-moon passes into earths umbra
partial lunar eclipse-moon passes into earths penumbra

20

types of solar eclipses

total solar eclipse-moons umbra falls on the earth
partial solar eclipse-moons penumbra falls on the earth
annular eclipse- ring is visible moon doesn’t quite cover the sun

21

how did the moon form

formed from a collision with a mars sized object
debris from collision accelerated into the moon
surface bombarded by meteorites

22

properties of the moon

gravity 1/6 of earths
rocks are igneous
average density is less than earths
mass is about 1/80 of earths

23

dark area of moons surface

maria-basins of basaltic rock 3.1-3.8 billion years old

24

lighter areas of moons surface

lunar highlands-on the edge of maria 4.0-4.30 billion years old

25

what causes tides

moons gravity and earths rotation

26

what is solar noon

occurs when the sun is at its highest point
does not occur at the same time for everyone
earth rotates 15 degrees per hour
every degree of longitude is 4 minutes of solar time

27

4 different time zones

eastern
central(-1)
mountain(-2)
pacific(-3)

28

what is the international dateline

180 degrees meridian
day starts and date changes when crossing it
moving west-add a day
moving easy-lose a day

29

what is a solar system

objects in orbit around the sun
includes:
planets, moons, asteroids, comets

30

greeks early solar system model

greeks thought that all planets orbited the earth
geocentric model

31

solar system formation

proto-planetary disc -cloud of gas and dust
gravity pulls particles together
sun forms-fusion of hydrogen
planets form from remaining material through accretion

32

inner planets

four planets nearest the sun
contains heaviest elements
have solid surfaces
dense cores
mercury,venus,earth and mars

33

asteroid belt

rocks and dust between mars and jupiter
debris never became a planet because of Jupiter’s gravity

34

outer planets

four planets beyond asteroid belt
jovian planets or gas giants
no solid surface
made up of gases
solid cores
Jupiter, Saturn, Uranus, and Neptune

35

kuiper belt

belt of debris at the edge of the solar system
dwarf planet pluto is the most massive object in belt

36

which planet is the most massive

jupiter

37

which planet have rings

saturn

38

what is olympus mons and valles marineris

volcano extinct on mars
huge canyon on mars

39

what holds planets in their orbits

the suns gravity

40

phases of the moon in order

new moon
waxing crescent
first quarter
waxing gibbous
full moon
waning gibbous
last quarter
waning crescent