Download Study Guide answers Ch 8

Study Guide: Science Ch 8- Earth’s place in the Universe
1. What is Rotation?
The motion of something turning on it’s axis
2. What does the earth’s rotation cause?
Day and night
3. What is revolution?
To circle around or orbit something else
4. What does the earth’s revolution cause?
years
5. What causes seasons?
The earth’s tilted axis, which causes some parts of the earth to be
closer to the sun at different times as the earth travels around the
sun.
6. What is an axis?
An imaginary line through the center of an object that it rotates
around
7. What is apparent motion?
The way something seems to move that is not real movement or
motion. For example, the way the sun appears to move across the
sky to rise and set, though the sun is not really moving (the earth
is!)
8. How are shadows and apparent motion related?
As your position in relation to the sun changes, the shape and size
of the shadow you cast also changes, so as the sun appears to
move, your shadow changes
9. What is the moon like?
Rocky, very thin atmosphere, many craters, smaller than the
earth, little water, extreme temperature variations between day
and night
10.
What are craters? What causes them?
A hollow area or pit in the ground, mostly caused by meteoroids
crashing into the moon. They do not hit earth’s surface so often
because of our atmosphere.
11.
Why does the moon look different on different days of the
month?
The moon has different phases based on it’s relative position to
earth- we see only the lighted side of the moon and cannot
always see the whole side that faces the sun.
12.
What are all phases of the moon, and what order do they
happen in?
New moon, waxing (growing) crescent, first quarter, waxing
gibbous, full moon, waning (shrinking) gibbous, third quarter,
waning crescent.
13.
What causes a lunar and solar eclipse?
A lunar eclipse is caused by the earth casting a shadow on the
moon so it cannot reflect light and appears dark.
A solar eclipse is caused by the moon coming between the earth
and sun, and casting a shadow on the earth. Within that shadow
the sun appears to be blacked out.
14.
What are planets?
Round objects in space that orbit the sun
15.
What are the 8 planets in our solar system?
Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune
16.
Know key facts about all planets. (relative location, relative
size, basic composition)
Mercury- nearest the sun, less than half the size of earth, smallest rocky
planet, no moon, little air
Venus- 2nd planet from the sun, thick atmosphere of mostly CO2, close
in size to earth (sometimes called earth’s twin), hottest planet with
many volcanoes
Earth- 3rd planet from the sun, the only planet to support life
Mars- 4th planet from the sun, most like the earth, colder than earth
and thinner atmosphere, called the red planet because of the high
concentration of iron rust in the soil.
Jupiter- 5th planet from the sun, first outer planet and gas giant, largest
planet, no solid surface, great red spot is a large storm
Saturn- 6th planet from the sun, has rings made of many orbiting
moons, dust, and space debris, gas giant (no solid surface)
Uranus-7th planet from the sun- “sideways” planet because it orbits on
it’s side, gas giant
Neptune- 8th planet from the sun- farthest gas giant
Other- Dwarf planets like Pluto, made of rock and ice
17.
What are 4 different ways we study space?
Telescopes- a tool to make far away things look near
Astronauts- people who go to, study, and explore space
Shuttles and space stations- used to take astronauts to space and
provide a place for experiments, the international space station is
continuously in orbit
Probes- an unmanned space craft that leaves earth’s orbit and
transmits information back to earth.
18.
What are comets, asteroids and meteoroids?
Comets- ice mixed with rocks and dust that moves in a long
narrow orbit around the sun
Asteroids- large chunks of rock or metal in space
Meteoroids- small pieces of comets or asteroids, called a
“meteor” if it enters earth’s atmosphere, and a “meteorite” if it
reaches earth’s surface
19.
How do we know the temperatures of distant stars?
By their color- different heats produce different colors when
burning. Blue or white is hotter, red or orange is cooler.
20.
How does our sun compare to other stars?
Our sun is a mid sized star, of average temperature. It only looks
larger and we can feel it’s heat because we are much, much,
closer to it than to other stars.
21.
What are light years?
The distance light can travel in one year.
22.
What are galaxies? What galaxy are we in? What is our next
nearest galaxy?
A large group of starts, we are in the Milky way, the next nearest
is Andromeda galaxy
23.
What are constellations?
A group of stars that make a pattern or picture in the sky
24.
Why do we see different constellations at different times?
We only see stars when facing away from the sun, so we see
different constellations as we travel around the sun. (the other
stars are still there, but our view is blocked by the sun)
25.
What are circumpolar constellations?
Constellations that appear to travel around the earth’s poles and
are visible year round, like the big dipper. This is because they are
“above” or “below” the earth, and therefore our view is never
blocked by the sun.
26.
Why is the sun important?
All life of earth is dependent on the sun- it provides all the energy
on earth, light and heat. It powers the water cycle, allows plants
to grow, etc.