Term
| Number of Stars in Milkyway Galaxy |
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Definition
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Term
Cosmic Adress: order of magnitude.
big to little
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Definition
Universe
Local Supercluster
Local Group
Milky Way galaxy
Solar system
Planet
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Term
How do we know universe is expanding
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Definition
Telescopic observatins. Average distances between galaxies is growing |
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Term
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Definition
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Term
| How do stars generate energy |
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Definition
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Term
| Death of A star is caused by |
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Definition
| Star runs out of usable fuel. No more stuff to nuclearly fuse. Star dies in a huge explosion called a supernovae. |
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Term
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Definition
| Material From dead stars turns back in other stuff |
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Term
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Definition
| 300,000 km meters per second |
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Term
| How long does it take light form sun to reach earth |
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Definition
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Term
| How big is one light year |
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Definition
| 10 trillion kilometers, 6 trillion miles |
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Term
| Diameter of Milky Way Galaxy |
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Definition
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Term
| Distance to alpha centari |
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Definition
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Term
Galatic rotation:
Time it takes earth to make one rotation around Center and distance from center
Speed our solar system as we orbit center |
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Definition
Time: 230 million years
Distance: 28,000 Light years
speed: 800,000 km per hour(500,000 mph)
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Term
| Most of the galaxy is made up of? where is this located? |
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Definition
| Dark matter. outside of visible disk |
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Term
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Definition
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Term
| about how many galaxies are in observabel universe |
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Definition
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Term
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Definition
| Region of the sky with well define borders |
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Term
| Parts of Celestial Sphere |
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Definition
| Celestial north and south pole. zenith. horizon. Direction. Altitude |
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Term
| Angular size of moon and sun |
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Definition
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Term
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Definition
fist 10 degrees
Hand spread 20
finger 1
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Term
| More precise atronomical measurements than degrees |
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Definition
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Term
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Definition
| Stars that remain perpetually above the horizon. Never rise or set, rather then makes counterclockwise circles around the north celestial pole. |
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Term
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Definition
Longitude ~ Up down lines of map
(measure east and W)
Latitude ~ Across lines
(measure north south)
Lat equator = 0 |
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Term
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Definition
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Term
| Determining your latitude |
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Definition
The north celestial pole(polaris) lies the same degree in the sky as your latitude. if its 40 in sky your at 40 N |
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Term
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Definition
| 12 constellations that lie along the ecliptic |
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Term
| What constellation are we in |
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Definition
Constellation - Earth- Sun- Constellation we are in.
The constellation that we cannot see is the constellation were in |
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Term
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Definition
| Daytime equal to nightime |
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Term
| Approximate dates of Equinoxs/solstices |
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Definition
Sum Sol: june 21
win sol: december 21
Spring Eq: march 21
fall eq: september 22 |
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Term
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Definition
| Moment where a hemisphere receives its most or least sunlight |
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Term
| Why does orbital distance affect our seasons |
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Definition
| Most land is in northern hemisphere. |
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Term
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Definition
| a gradual wobble that changes the orientation of Earths axis in space cycle takes about 26,000. caused by gravities affect on a tilted rotating object that is not a sphere |
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Term
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Definition
6am rise
highest noon
6am set
u dont see it its between us and sun |
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Term
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Definition
6pm rise
midnight highest
6am set
Sun earth moon |
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Term
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Definition
3 hour changes
New-Waxing Crescent(light on right)-First Quarter(half)- Waxing gibbous- Full Moon Waning Gibbous(light on left)- third quarter - waning crescent |
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Term
| Average earth moon distance |
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Definition
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Term
| time from one new moon to the next |
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Definition
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Term
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Definition
| You always see earth in a phase opposite the one you are in |
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Term
| Lunar Eclipse vs Solar Eclipse |
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Definition
Lunar: Sun - Earth- Moon
solar: sun - moon -earth |
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Term
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Definition
Moon orbits at 5 deg tilt therefore it only passes through ecliptic twice per cycle. these passing are called Nodes.
two conditions: Moon must be full moon(lunar) New Moon (solar)
New or full must occur during one of the periods when the nodes of the moons orbit are aligned with sun and earth |
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Term
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Definition
| Where sun is completely blocked eclipse |
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Term
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Definition
| where sun is only partially blocked |
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Term
| How did astronomy benefit ancient society |
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Definition
Calendars
wet seasons/crops
clock
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Term
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Definition
| Proposed first model of universe that did not involve supernatural forces |
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Term
Ptolemy and Ptolemaic Model
whats wrong |
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Definition
Synthesis of Geocentric Model
geocentric, and believe as planets orbited earth they did small circles
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Term
| Copernicus Copernican revolution |
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Definition
| Spurred the developement of virtually all modern science. he was able to use geometry to calculate orbital periods of planets making him beleieve in was a heliocentric |
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Term
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Definition
| He was convince planets must orbit sun but believed earth was stationary |
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Term
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Definition
| discovered orbits were elipses. two foci. laws of planetary motion |
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Term
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Definition
1) orbit of each planet around the sun is and elipse. with the sun at one focus. closest point perphelion, fartherest aphelion.
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Term
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Definition
| 2) As a planet moves around its orbit it sweeps out equal areas in equal times |
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Term
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Definition
| the more distant a planets orbit at slower speeds. p2=a3 |
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Term
| Galileo How he solidified copernican revolution |
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Definition
| dismissed aristotles bullshit |
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Term
| Order of Early Astronomers |
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Definition
| Aristotle, Ptolemy, Copernicus, Tycho, Kepler, Galileo |
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Term
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Definition
1) Modern Science seeks explanations for observed phenomena that rely solely on natural causes
2) Science progresses through the creation and testing of models of nature that explain the observations as simply plausible
3) A scientific model must make testable predictions about naturable phenomena that would force us to revise or abandon the model if the predictions do not agree with observations |
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Term
| diameter of earth roughly |
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Definition
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Term
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Definition
An object at moves at constant velocity if there is no net force acting upon it
F= m times acceleration
For every force there is an equal and opposite reaction force |
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Term
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Definition
| kinetic, radiative, potential |
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Term
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Definition
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Term
| How newtons laws changed shit |
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Definition
| showed that the same physical laws that operate on earth also operate in the heavens. this allows us to study physical laws on universe here on earth. |
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Term
| Conservation of angular momentum |
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Definition
| a planets rotation cannot change unles it transfers angular momentum to another object |
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Term
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Definition
| newton proved orbital shapes can be unbound parobolas or hypebolas. |
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Term
| How does gravity and energy together allow us to understand orbits |
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Definition
| an object cannot change its orbit unles it gains/loses orbital energy. (grav eng+ kinetic eng). |
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Term
| Power in relation to light |
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Definition
| ipower is the rate of energy transfew, measured in watts. 1 watt = 1 joule. the color of light contains a great deal of information about the matter which it has interacted |
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Term
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Definition
| Light is an electromagnetic wave, but also comes in peices called photons. each photon has a percise wavelength frequency and energy. |
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Term
| Energy of light how to tell |
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Definition
| The shorter the wave length, the higher the frequency and energy |
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Term
| What is the electromagnetic spectrum |
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Definition
In order of decreasing wavelength.
Radio waves, microwaves, infared, visible light, ultraviolet, x rays, gamma rays |
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Term
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Definition
| have same number of protons but diff number of neutrons. |
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Term
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Definition
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Term
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Definition
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Term
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Definition
| Ionized gas. occurs at very high temps when high temps strip strips electrons from atoms |
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Term
| Energy levels info (transitions) |
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Definition
electrons can exist only in particular energy levels within an atom.
Electrons can only make energy level transitions when electron gains or loses a specific amount of energy |
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Term
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Definition
Looks like a rainbow of light. hot light source through prism |
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Term
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Definition
| warm gas clouds emit light at only specific wavelengths. produces abunch of colored lines when passed through prism. |
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Term
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Definition
| Hot light source goes through cooler cloud of gas then through prism. dark absorption lines where the cloud has absorbed light of specific colors. |
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Term
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Definition
| emitted by most objects. most common type of continuous spectra. we can determine temp from these spectra because hotter objects emit more total radiation per unit are and emit photons with a higher average energy. |
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Term
| Doppler effect (blueshift vs redshift) |
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Definition
| this tells us how fast an object is moving toward or away from us. Psectral lines are shifted to shorter wavelengths(a blueshift) in objects moving toward us and to longer wavelengths(red-shift). in onjects moving away from us. |
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Term
| Doppler effect and rotation |
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Definition
| dopler effect broadens spectral lines of rotating objects. the faster the rotation, the wider the spectral line. |
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Term
| How your Eye works and Parts |
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Definition
| Your eye brings paralell rays of light to a focus on your retina. Glass lenses work similarily, so distant objects form an imagine that is in focus on the focal plane. |
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Term
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Definition
| we record images with a detector such as photographic film or a ccd. recorded images are more reliable than just seeing by eye and can record more light if we use a long exposure |
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Term
| Two most important parts of a telescope |
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Definition
| Light collecting area(how much light it gathers) and angular resolution(how much detail) |
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Term
| Two types of telescopes how they work(be able to draw) |
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Definition
| A refracting telescope forms an image by bending light through a lens. reflecting telescope forms an image by focusing light with mirrors |
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Term
| Three primary uses of a telescope |
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Definition
| Imaging, spectroscopy, timing(brightness changing over time) |
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Term
| Things from earth that affect ground based telescopes |
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Definition
| light pollution. atmospheric turbulence makes shit twinkle. |
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Term
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Definition
| technology that can overcome turbulence |
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Term
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Definition
| turbulence, light pollution. telescopes in space can view all wave lengths. on ground only visible radio and some infared. |
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Term
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Definition
| 108Rearth. 98% hydrogen. Contains more than 99.9% of solar systems mass. |
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Term
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Definition
| Terrestrial. .4 Rearth. Rocks and metals. Hot and cold extremes 0 atmosphere. Unusual rotation pattern. rotates exactly 3 times for every 2 times in circles sun. 425 C during day. Wrinkles indicate planetary shrinking. Cratered. |
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Term
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Definition
| .95Rearth. rocks metals. Average surface temp 740K(hotter than mercury). No moons. No oxygen. Sulfuric rain. runaway greenhouse. volcanoes. |
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Term
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Definition
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Term
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Definition
| .53 earth radius. average surface temp 220k. .11 mass of earth. 2 moons small. |
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Term
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Definition
| 1st Jovian Planet. 11.2 Earth Radius. Moons atleast 63. 318 earth masses. Know four moons. moslty hydrogen and helium. |
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Term
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Definition
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Term
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Definition
| 9.54 Au. 9.4R earth. 95.2Mearth. mostly hydrogen and helium. atleast 60 moons. lower density than jupiter. Know Titan. |
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Term
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Definition
| 19.2 AU. 4Rearth. Mass 14.5Earth. Hydrogen, Helium. 60K. 27 moons. Tipped on side caused by collision? Extreme seasons. 42 year nigth 42 yr day on north pole. |
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Term
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Definition
| 30.1 AU. 3.9EarthR. 17.1Earth Mass. Moons 13. Largest moon Triton larger than pluto. Has a moon that orbits its moons backwards. Triton was probably independant. |
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Term
| Pluto and other dwarfs features. |
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Definition
| .18Rearth. ice rock. 3 moons. 40AU |
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Term
| 3 things that provide clues to how solar system was formed |
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Definition
1) Sun, planets, and large moons generally rotate and orbit in a very organized way.
2) The first eight planets from the sun divide clearly into two groups Jovian and terrestrial
3) the solar system contains huge numbers of asteroids and comets
4) there are some notable exceptions to these patterns |
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Term
| Exceptions in solar system |
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Definition
| Uranus on Its Side.Triton orbits backwards. Venus spins clockwise |
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Term
| Types of Robotic Explatory Space Craft |
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Definition
| Flyby, orbiter, lander/probe, sample return. |
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Term
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Definition
| stars and planet formed from a nebular cloud. stuff condensed. |
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Term
| Why close encounter theory is wrong |
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Definition
| doesnt account for observed orbital motions, or the division(jovian terrestrial) far too improbable. |
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Term
| Explain HEating Spinning Flatening Idea |
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Definition
Heating: temp of solar nebular increased as it collapsed. such heating represents energy conservation. cloud collapsing, these particles collapsed into one another. kinetic energy, Sun formed at center where energy was highest and densest.
Spinning: solar nebula spin faster as shrunk. conservation of ang momentum. this ensured not all material collapsed to center. Greater ang momentum more spread out.
Flattening: nebula flattens into a disk. particle collision causes cloud to be flatter |
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Term
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Definition
| Hydrogen converted to other elements these elements bunch up to form planets |
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Term
| Composition of solar nebula |
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Definition
Hydrogen 98%
H compounds 1.4%
Rock .4%
metal .2% |
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Term
| Condesing of solar nebula peices |
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Definition
| gases do not condense. h compounds icy solidification, rock high temp same with metal |
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Term
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Definition
| point where hydrogen compounds can freeze then condense |
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Term
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Definition
| process of how planetary seeds grow into planets |
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Term
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Definition
| a streamed of charged particles. it contiually blown outwar in all directions from the sun. blows away gas |
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Term
| How does solar wind seal fate of planets |
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Definition
| it blows away gases that might have otherwise condensed into ice |
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Term
| Explain suns slow rotation why not fast |
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Definition
| angular momentum. transfered energy to winds. |
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Term
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Definition
| asteroids comets outside jovian planets |
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Term
| Total mass of asteroids in asteroid belt |
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Definition
| fraction of any terrestrial planet |
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Term
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Definition
| massive collisions between planets and planetesimals |
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Term
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Definition
| hard to break from an unbound orbit to a bound one unless is somehow loses orbital energy. Friction from the gases in early solar system may have caused this |
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Term
| Where did our moon come from |
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Definition
| a massive collision with a mars size planetesimal |
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Term
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Definition
| caused by an impact that blasted away outer layers |
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Term
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Definition
| comparing amount of one element compared to element in decayed into |
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Term
| Inside of terrestrial PLanets |
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Definition
| Core, mantle, and crust. Crust and part of mantle make up lithosphere |
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Term
| Main source of heat in terrestrial planets today |
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Definition
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Term
| What three things are needed for a planetary magnetic field |
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Definition
1) interior layer of electrically conducting fluid
2) convection of that fluid
3) rapid rotation
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Term
| What is major factors contributed to a planets geological history |
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Definition
| Size determines volcanism, tectonics |
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Term
| What cause planet surface erosion |
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Definition
| size, distance from sun, rotation rate |
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Term
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Definition
| vast darm lava plains on moon |
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Term
| why does moon not have erosion |
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Definition
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Term
| why does mercury have tectonic cliffs |
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Definition
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Term
| Why Venus shows little erosion |
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Definition
slow rotation = no wind
no rain |
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Term
| Why venus shows no tectonics |
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Definition
| heat may have baked out moisture in lithosphere making it harder than earths |
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Term
| Evidence of Plate Tectonics |
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Definition
| continents fit together. new crust creation on sea floor. compositional differences between seafloor and continental crust. |
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Term
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Definition
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Term
| What do S waves tell us about core of Planet |
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Definition
| that it is partialy liquid |
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Term
| 3 major heat sources for planet interiors |
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Definition
Heat of Accreation impacts turn to heat
Heat of differentiation~ light float dense sink grav potential to kinetic
Radioactive decay |
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Term
| what four processes shape planets surface |
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Definition
Impact cratering
Volcanism
Tectonics
Erosion |
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Term
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Definition
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Term
| Wide but not steep volcanoes |
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Definition
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Term
| Large terristial planets have? |
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Definition
| Warm interior mantle convection. Tectonic volcanic interior. outgassing produces atmosphere gravity holds on to it. (core can also be molent producing magnetic field if rotation is fast enough) |
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Term
| Rapid rotation is necessary for |
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Definition
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Term
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Definition
| layer of gas that surrounds world. absorbes scatters light, creates pressure, wind weather, interacts with solar wind to create magnetosphere, greenhouse effect |
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Term
| Layers of atmosphere closest to fartherst |
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Definition
| troposphere, stratosphere, thermosphere, exosphere |
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Term
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Definition
| where most greenhouse warming occurs. |
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Term
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Definition
| where ozone absorbs ultraviolet light |
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Term
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Definition
| where solar x rays are absorbed |
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Term
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Definition
| low density outer layer of atmosphere |
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Term
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Definition
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Term
| what has caused longterm climate changes |
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Definition
| change in axis tilt. changes in reflectivity. chnages in greenhouse gas abundance. |
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Term
| loss processes for atmosphere |
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Definition
| condensation, chemical reactions with surface materials, blasting away by impacts, stripping of gas by solar winds, thermal escape |
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Term
| how atmosphere is created |
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Definition
| sandblasting, outgassing, evaporation or sublimation, |
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Term
| how did mars lose atmosphere |
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Definition
| solar wind. planet cooled. lost atmosphere. and magnetosphere |
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Term
| runaway greenhouse effect |
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Definition
| gets too hot to have liquid ocean. it evaporates. no ocean to disolve carbon dioxide. no rocks to put compress carbonate. |
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Term
| what stabalizes climate on earth |
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Definition
| carbon dioxide cycle. feedback system. |
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Term
| why did earths temp end up so diff |
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Definition
| oceans to dissolve co2,temps were right for outgased water vapor to condense into oceans. o2 and ozone produced by photosynthesis. |
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Term
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Definition
| 20,000 stronger than earths. Can occur because jupiter has an electrically conducting fluid region that is made of metallic hydrogen + rapid rotation. Io contributes alot of charged particles to magnetosphere. |
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Term
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Definition
| Io, Europa, Ganymede, Calisto |
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Term
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Definition
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Term
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Definition
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Term
Two Largest Jovian Moons
(larger than mercury) |
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Definition
Saturns Titan
Jupiters Ganymede |
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Term
| How are the large jovian different from Terrestrial planets |
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Definition
| Differ in compositions b/c they formed in the cold out solar system which contains alot of ice in addition to rock and metal |
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Term
| How were most of these moons formed (jovian) |
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Definition
| Accretion within jovian disks. this explains their rotation. they always keep face toward planet |
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Term
| What is weather like on jovian planets |
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Definition
| Storms layers of clouds with different stuff in them gives them different colors. |
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Term
| Why are jupiters galilean moons so geologically active |
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Definition
| Io most active. INteriors kept hot by tidal heating. this occurs on io because lose orbit is made elliptical by orbital resonacnes with other moons. Europa (maybe ganymede) have oceans under ice also thanks to tidal heating. Callisto least geologically active no orbital resonance or tidal heating. |
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Term
| What is remarkable about titan and other major moons in outer solar system |
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Definition
| Past and present volcanism or tectonics. titan has thick atmosphere caused by ongoing erosion of liquid methane. Triton was apparentyl captured by neptune geologic activity too. |
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Term
| WHy are small icy moons more geologically active then rocky planets |
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Definition
| Ice deform and melt at much lower temps. allowing icy volcanism and tectonics at low temps. some jovian moons also have tidal heating |
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Term
| most volcanically active world in solar system |
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Definition
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Term
| Galilean moons small to large |
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Definition
| europa, io, callisto, ganymede |
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Term
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Definition
| rocky leftover from era of planetry formtion (total mass of all of them less than ay terrestrial planet) |
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Term
| Why is there an Asteroid Belt |
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Definition
| Orbital resonances from jupiter fucked up the orbits of planetesimals. this prevented them form forming planet. many ejected some remain in what is known as asteroid belt. |
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Term
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Definition
| are remnants of the solar nebula. intermixed rocks and flakes. some are rich in carbon compounds. |
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Term
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Definition
| are fragments of larger asteroids and theefore can be metallic like a planets core or rocky like its mantle |
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Term
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Definition
| icy leftover from planet formation. if comet approaches sun its nucleus heats up and its ice sublimates into gas. this escape gas and dust create what is know as the comet coma nd two tails. |
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Term
| What are the two tails of a comet |
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Definition
plasma (ionized gas) tail
dust tail |
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Term
| Where do comets come from |
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Definition
| Kuiper belt or Oort Cloud |
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Term
| Have we discovered any earth size planets |
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Definition
|
|
Term
| why is it so difficult to detect stars around other plnets |
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Definition
| the great distances to stars nd the fat tht typical stars are billion times brighter than the light reflected from any of their planets makes it very difficult to detect extrasolar planets. |
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Term
| What is the astrometric Technique |
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Definition
| looks for planets gravitational effect on its star. which looks for small shifts in stellar position |
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Term
| Doppler technique for finding planets |
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Definition
| looks for back and forth motion of stars revealed by doppler shifts |
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Term
| For methods for finding other planets |
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Definition
Astrometric technique
doppler technique
looking for transits and eclipses |
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Term
| technique most effective for finding other planets |
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Definition
|
|
Term
| characteristics of extrasolar planets |
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Definition
| more massive than earth. close to there stars, large orbital eccentricies. little info on size or compositions. consitent that the planets jovian in nature |
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Term
| why do these extrasolar planets have low denisites compared to our jovians |
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Definition
| orbit close to the sun puffs them up hot jupiters. |
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Term
| Explain the surprising orbits of extrasolar planets |
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Definition
| probably formed like our jovians but some other force made them move in. migration caused by waves in gaseous disk they formed in or encounters with other objects, or resonances of other planets |
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Term
| why was the suns source of energy such a mystery |
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Definition
| before we knew how far away it was we did not know its output of energy. Enstein. |
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Term
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Definition
| Gravitational equilibrium keeps the core hot and dense enough to release energy through nuclear fusion. the core originally became hot trhough the release of energy caused by gravitational contraction. |
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Term
| Parts of Suns interior layers |
|
Definition
Core, radiation zone, convection zone, photosphere inside
chromosphere corona outside. |
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Term
| how does nuclear fusion occur in sun |
|
Definition
Hot and dense enough that hyrdogen can be converted in helium 4. proton-proton chain reaction whihc acts like a thermostat
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|
Term
| how long does it take energy from core of sun to reach photosphere |
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Definition
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|
Term
| Process of how energy moves from cor to surface of sun |
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Definition
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|
Term
| How do we know whats going on inside sun |
|
Definition
| we can study neutrinos and solar vibrations |
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Term
| What causes solar activity |
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Definition
| Convection combined with the rotation of the sun faster at equator than pole gas motions stretch and twist suns magnetic field. |
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Term
|
Definition
| sunspots, flares, prominences, coronal mass injections |
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|
Term
| how solar activity affect humans |
|
Definition
| it jams satelite and radio |
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Term
|
Definition
| Magnetic field flip flops every 11 yrs. 22 year magnetic cycle. |
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Term
|
Definition
Order
reproduction
growth and developement
energy utilization
respond to enviroment
evolutionary adaptation |
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Definition
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Definition
| water, nutrients, fuel/energy |
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Term
| Why arent big stars good for life |
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Definition
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Definition
| relatively small, Not huge. Have stable orbits. planets in a habital zones. |
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Definition
| Oh Be A Fine Girl Kiss Me |
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| Spectral types that could have life |
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Definition
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Definition
Galatic constraints(too far out not enough heavy metals, too far in supernovae).
Impact rates
Climate Stability(we have Moon and tectonics |
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