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96 Cards in this Set

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  • Back

What is our Cosmic address?

you, earth, solar system, Milky way, local group, local supercluster

What is a light year?

distance traveled by light in 1 year

What is the difference between a theory and a hypothesis in science?

A hypothesis is an idea that will be tested but a theory is and idea that has survived repeated and varied testing.

how old is the Universe? How big is the universe?

Between 10 billion and 16 billion years
What do astronomers mean when they say that we are made of "star stuff"?

Carl Sagan said we are made up of star stuff because we are made up of the elements that were created and once inside of a star. Stars die and explode violently, thus scattering their stuff around!

What is the Doppler Effect and how does it help describe the motion of astronomical objects?

The doppler effect shows (pitch) wavelength changes for a moving source.

Redshift is the doppler effect for an object moving away from us.

What are constellations?

Stars that look like they are together

What is the ecliptic?

Sun's apparent annual path around celestial sphere

What is the celestial sphere?

The celestial sphere is an imaginary sphere with the earth at its center. The sky overhead is the half of the sphere we see from earth, appearing as a dome

Why do we have seasons?

The tilt of the Earth contributes to the concentration of sunlight we get and the length of our days, thus creating seasons


put together the most comprehensive geo-centric model.

took out sphere, replaced with orbit (epicycles)


says all planets revolved around sun.

planets move at different speeds, further away the slower.

Didn't publish book until deathbed


did not invent telescope, but first to use it for astronomy.

noticed 5 things:

1. moons orbiting jupiter. This shows Earth was not center of all motion

2. observed phases of Venus. The proved Venus went around Sun.

3. observed mountains, oceans, and craters on Moon. proved moon was not heavenly object

4. imperfections on Sun. found sun rotates like ordinary object

5. resolved milky way into multitude of stars showing they are further away than previously thought


collected data on movement of planets.

said all planets revolve around the Sun, which revolves around Earth


analyzed Brahe's data.

planets traveled in ellipses around the sun

Laws of planetary motion

Kepler's laws of planetary motion

1. planets travel in ellipses around the sun, and the sun is one of the foci

2. there is an imaginary line that sweeps from the sun and covers equal areas in equal times,the elliptical orbit. this means that the closer the planet is to the sun in its orbit, the faster it will travel and vice versa.

3. the distance a planet is away from the Sun obeys a precise mathematical relationship to its speed. p^2=a^3 p being its revolution in years, and a being its semimajor axis in AU's

Newton's laws of motion

1. States that if an object is at rest of in uniform motion in a straight line, it will remain constant unless acted upon by a net external force

2. states that acceleration of an object is directly proportional to its net external force, and inversely proportional to its mass

3. States that for every force, there is an equal but opposite force

Explain why an astronaut appears to be weightless inside the space shuttle

They are in continuous free-fall

3 types of visible light spectra. Describe what each looks like

Continuous line - rainbow with now color interruption

Emission line - black background with sporadic color lines

Absorption line - rainbow background with sporadic black lines

Draw and label a diagram to illustrate what happens to light inside a telescope with a Newtonian Focus

Name and describe 4 processes that shape planetary surface

1. Tectonics -stretching or compression of plates crust

2. Volcanism - magma coming up from below and forming volcanos

3. Erosion- wind, water, and ice slowly breaking down the land

4. Impact Cratering- large impacts that crater the land

List 4 basic types of spacecraft missions. Give an actual example of each type

a. flybys - crafts that literally flyby a planet, these are most affordable

b. orbiters - crafts that are placed into a planets orbit to gather data

c. landers - crafts that land on a planet and can explore with rovers

d. sample return - crafts that go to a planet, land, gather samples, then come back so we can analyze the data

Name and describe 4 types of interactions between lithospheric plates

1. Divergent-the plates move away from each other Ex. Mid Atlantic Ridge

2. Convergent-plates move towards each other

a. Subduction-one plate goes under the other plate Ex. Japan Trench

b. Collision- plates crash, wrinkling the plates Ex. Himalayan Mountains

3.Transform Fault Margin- the plates move perpendicular to each other Ex. San Andreas Fault Line

how does a planetary greenhouse effect work? Is it good or bad? Explain

Greenhouse gases absorbs and re-emit infrared radiation, thereby heating the lower atmosphere.

It is good because it keeps the temperature balanced.

Describe two differences between asteroids and comets

asteroids are small rocky bodies that orbit the sun.

Comets are icy bodies that orbit the sun. They leave a trail of dust.

Explain the difference between a) meteoroids b) meteors c) meteorites

Meteoroids- small asteroid orbiting the sun

Meteors- a small body of matter from outer space that enters the earth's atmosphere.

Meteorites- a meteor that survives its passage through the earth's atmosphere such that part of it strikes the ground.

What is differentiation in planetary geology?

the process by which gravity separates materials according to desnity

The lithosphere of a planet is the layer that consists of

the rigid rocky material of the crust and uppermost portion of the mantle

which internal energy source is the most important in continuing to heat the terrestrial planets today?


which of the following most likely explains why Venus does not have a strong magnetic field?

It's rotation is too slow

when we see a region of a planet that is not as heavily cratered as other regions, we conclude that

the surface in the region is younger than the surface in more heavily cratered regions

how did the lunar Maria form

large impacts fractured the moon's lithosphere, allowing lava to fill the impact basins

why does the moon have a layer of powdery soil on its surface?

it's the result of gradual erosion by micrometeorites striking the moon

why do we think mercury has so many tremendous cliffs?

they were probably formed by tectonic stresses when the entire planet shrank as its core cooled

Olympus Mons is a

shield volcano on Mars

how have we been able to construct detailed maps of surface features on Venus?

by using radar from spacecraft that were sent to orbit Venus

What is the frost line of the solar system?

the distance from the Sun where temperatures were low enough for hydrogen compounds to condense into ices, between the present day orbits of Mars and Jupiter

The age of our solar system is ~

4.6 billion years

According to our theory of solar system formation, why do all the planets orbit the Sun in the same direction an din nearly the same plane?

The laws of conservation of energy and conservation of angular momentum ensure that any rotating collapsing cloud will end up as a spinning disk

why did the solar nebula heat up as it collapsed?

as the cloud shrank, its gravitational potential energy was converted to kinetic energy and then into thermal energy

which of the following are relatively unchanged fragments from the early period of planet building in the solar system?

a. asteroids

b. oort cloud comets

c. Kuiper belt comets

d.the moons of Mars

e. all of the above

e. all of the above

which of the following is the origin of almost all the large moons around the Jovian planets?

a. they are captured planets

b. they are captured asteroids

c. they are captured comets

d. they were formed by giant impacts

e. they were formed by condensation and accretion in a disk of gas around the planet

e. they were formed by condensation and accretion in a disk of gas around the planet

where did the elements heavier than hydrogen and helium come from?

They were produced inside stars

Describe the modern theory of how our moon was formed

The theory is that a giant impact occurred with Earth from a molten planetesimal. This impact and the devestation it caused, left material to form the moon.

explain why the era of planet formation ended

Nuclear fusion in the sun made it get hotter, which caused solar winds, which swept away the raw material from the solar nebula, thus eliminating the material to form future planets

At extremely high temperatures (millions of degress), describe the phase of matter

a plasma consisting of positively charged ions and free electrons

from laboratory measurements, we know that a particular spectral line formed by hydrogen appears at a wavelength of 121.6 nanometers. The spectrum of a particular star shows the same hydrogen line appearing at a wavelength of 121.8nm. What can we conclude?

The star is moving away from us

If we observe one edge of a planet to be redshifted and the opposite edge to be blueshifted, what can we conclude about the planet?

The planet is rotating

Without telescopes or other aid, we can look up and see the moon in the night sky because it

reflects visible light

the frequency of a wave is

a. measured in cycles per second

b. the number of peaks passing by any point each second

c. measured in hertz

d. equal to the speed of the wave divided by the wavelength of the wave

e. all of the above

e. all of the above

when an electron in an atom goes from higher energy state to a lower energy state, the atom

emits a photon of a specific frequency

an electron-volt is

a. an amount of energy much larger than a joule

b. an amount of energy much smaller than a joule

c. the charge of one electron

d. the energy of one electron

e. the energy jump between the first and second energy levels of hydrogen

b. an amount of energy much smaller than a joule

the wavelength of a wave is

the distance between two adjacent peaks of the wave

grass looks green because

it reflects green light and absorbs other colors

we can learn a lot about the properties of a star by studying its spectrum. Which of following is false?

a. we can id chemical elements present in the star by recognizing patterns of spectral lines that correspond to particular chemicals

b. the total amount of light in the spectrum tells us the stars radius

c. the peak of the stars thermal emission tells us its temperature. Hotter stars peak at shorter (blue)

d. we can look at Doppler shifts of spectral lines to determine the star's speed toward or away from us

b. the total amount of light in the spectrum tells us the stars radius

How are wavelength, frequency, and energy related for photons of light?

longer wavelength means lower frequency and lower energy

consider at atom of gold in which the nucleus contains 79 protons and 118 neutrons. What is its atomic number and atomic weight?

The atomic number is 79, and atomic weight is 197

List the 7 categories of electromagnetic radiation in order of increasing wavelength (list the category with the shortest wavelength first)

Gamma rays

x rays

ultraviolet rays

visible light

infrared light

microwave rays

radio waves

You are standing on a scale in an elevator. suddenly you notice your weight decreases. What do you conclude?

the elevator is accelerating downwards

Suppose an object is moving in a straight line at 50 mph. According to Newton's first law of motion, the object will

continue to move in the same way until it is acted upon by a force

how does the Space Shuttle take off

a. its rocket engines push against the launch pad propelling the shuttle upwards

b. hot gas shoots out from the rocket and, by conservation of momentum, the shuttle moves in the opposite direction

c. it converts mass-energy to kinetic energy

d. it achieves lift from its wings in the same way airplanes do

e. the hot rocket exhaust expands the air beneath the shuttle, propelling it forward

b. hot gas shoots out from the rocket and, by conservation of momentum, the shuttle moves in the opposite direction

According to the Universal Law of Gravitation, the force due to gravity is

a. directly proportional to the square of the distance between objects

b. directly proportional to the distance between objects

c. inversely proportional to the distance between objects

d. not dependent on the distance between objects

e. inversely proportional to the square of the distance between objects

e. inversely proportional to the square of the distance between objects

According to the Universal Law of Gravitation, if you double the masses of both attracting objects, then the gravitational force between them will

a. not change at all

b. decrease by a factor of 2

c. decrease by a factor of 4

d. increase by a factor of 2

e. increase by a factor of 4

e. increase by a factor of 4

the tides on Earth are an example of

a. Newton's first law of motion

b. Newton's third law of motion

c. Newton's second law of motion

d. the universal law of gravitation

e. none of the above

d. the universal law of gravitation

What quantities does angular momentum depend on?

a. linear momentum and orbital energy

b. force and radius

c. mass and velocity

d. force, velocity, and radius

e. mass, velocity, and radius

e. mass, velocity, and radius

what does temperature measure?

a. average mass of particles in a material

b. total kinetic energy of particles in a material

c. average size of particles in a material

d. average kinetic energy of particles in a material

e. total number of particles in a material

d. average kinetic energy of particles in a material

What is energy? List 3 general categories of energy and give an example of each

energy is the ability to work, measured in units of joules of calories.

Kinetic energy is about movement, such as movement of molecules.

Potential energy is the amount held within a forcefield such as a book on a bookshelf.

Radiant energy is the amount that is emitted from an object such as light from the sun

The path that led to modern science emerged from ancient civilizations in which part of the world?

Mediterranean and Middle East

how did Eratostheneses estimate the size of Earth in 240 BC

by comparing the maximum altitude of the Sun in two cities at different latitudes

how did the Ptolemaic model explain the apparent retrograde motion of the planets

it held that planets moved along small circles that moved on larger cycles around Earth (epicycles)

The controversial book of this famous person, published in 1543 (the year of his death) suggested that Earth and other planets orbit the sun


He discovered that the orbits of planets are ellipses


He discovered that Jupiter has moons


From Kepler's third law, an asteroid with an orbital period of 8 years orbits at an average distance from the Sun equal to

a. 2 AU

b. 4 AU

c. 8 AU

d. 16 AU

e. it depends on the asteroids mass

b. 4 astronomical units

(8^2 = a^3)

(64 = a^3)

(3squareroot 64 = a = 4)

Kepler's second law implies that

a planet travels faster when it is nearer to the Sun and slower when it is farther from the sun

How did Copernicus explain apparent retrograde motion?

He said the further a planet was from the Sun, the slower it went, meaning that when we observed it, it would appear to be going backward, when we were passing it.

how many stars can you see with your naked eye on a clear, moonless night from a dark location?

a few thousand

which of the following correctly describes the meridian in your sky?

a. a half circle extending from your horizon due east, through the north celestial pole to your horizon due west

b. the point directly over you head

c. a half circle extending from your horizon due north, through your zenith, to your horizon due south

d. a half circle extending from your horizon due east, through your zenith, to your horizon due west

e. the boundary between the portion of the celestial portion of the celestial sphere you can see at any moment and the portion that you cannot see

c. a half circle extending from your horizon due north, through your zenith, to your horizon due south

What exactly is a circumpolar star

a star that always remains above your horizon

what makes the north star, polaris, special

it appears very near the north celestial pole

Orion is visible on winter evenings but not summer evenings because of

a. the tilt of earth's axis

b. location of earth in its orbit

c. interference from the full moon

d. precession of earth

e. baseball on television

b. the location of Earth in its orbit

which of the following is not a phase of the moon?

a. new moon

b. first quarter moon

c. third quarter moon

d. half moon

e. full moon

d. half moon

when would you be most likely to first see a waxing crescent moon?

a. at sunrise

b. at least 50 minutes past sunrise

c. noon

d. at least 50 minutes past noon

e. at midnight

b. at least 50 minutes past sunrise

why do we see essentially the same face of the moon at all times

because the moon's rotational and orbital periods are equal

the tilt of the earth creates two effects that are the direct causes of the seasons. What are they

1. concentration of sunlight

2. length of daylight

The summer solstice is sometimes called the first day of summer and the winter solstice is sometimes called the first day of winter. list 2 things that happen at the summer solstice and 2 things that happen at the winter solstice

Summer -

1.longest path from sun

2. tilt closest to sun

3. sun rises in North


1. Shortest path from sun

2. tile furthest away from sun

3. sun rises in the South

List 2 conditions that must be met in order to produce a solar eclipse and 2 conditions that must be met to produce a lunar eclipse


1. new moon

2. moon is between Sun and Earth


1. full moon

2. Earth is between Moon and Sun

Roughly how many stars are in the Milky way galaxy

100 billion

What do we mean when we say the universe is expanding?

average distances are increasing between galaxies

What is nuclear fusion?

a. process of splitting nuclei to produce energy

b. a process that only occurs in bombs

c. process of turning matter into pure energy

d. process of combining lightweight nuclei to make heavier nuclei

e. an explosion caused by putting together two volatile chemicals

d. process of combining lightweight nuclei to make heavier nuclei

what is the sun mainly made of

hydrogen and helium

if you represented each star by a grain of sand, how much sand would it take to represent all the stars in the universe

more than all the sand on all the beaches on Earth

On a cosmic calendar, in which the history of the universe is compressed into 1 year, when did the dinosaurs become extinct?

in late december

Explain what we mean when we say "the farther we look in distance, the further we look in time"

We can see ~14 billion light years away, meaning we are seeing the edge as it was ~14 billions years go. Light years are the distance light travels in a year, thus if we see 4 light years away, light took 4 years to travel and we are seeing 4 years in the past.

What is a runaway green house effect?

A positive feedback cycle where the greenhouse gases are part of a cycle that produces more gases, until it heats up to the point of no return. instead of keeping balanced, the effect ran away. This happened on Venus.

Name the planets (from closest to Sun to furthest) and one distinguishing fact about them

Mercury- closest to sun

Venus- extreme greenhouse effect bakes surface

Earth- only planet with life

Mars- furthest terrestrial planet from the Sun

Jupiter- biggest planet, big red spot

Saturn- know for it's big visible rings

Uranus-extreme tilt on it's axis (sideways)

Neptune- furthest planet from the sun. Blue