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63 Cards in this Set
- Front
- Back
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What is Redshift/Blueshift? |
When an object is moving away, its wavelength gets longer, slower, and weaker. (Blueshift is the opposite) |
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Short wavlengths are... Long wavelengths are... |
fast, strong slow, weak |
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What is Hubble's Law? |
The further an object is away, the faster it is moving. If all galactic movement was reversed, everything would start from a single point, about 13.7 billion years ago. |
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What is Hubble's constant? |
The rate at which the universe is expanding 73 megaparsecs |
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What creates fusion? |
Hydrogen atoms collide in the core of the sun, which creates helium and a crap ton of energy |
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Describe convection currents. |
Molecules get cold, compact, become more dense, and sink. A heat source at the bottom of the cycle heats up the molecules, making them spread apart, become less dense, and rise. At the top of the cycle, some heat is released. |
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Sun is made up of what? |
25% helium 73.4% hydrogen |
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How many years does our sun have left? |
5 billion |
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What happens between the sun's core and its radiation zone? |
Fusion occurs in the core, and produces gamma rays because it's so hot that it doesn't produce visible light, but the radiation zone slows and cools the gamma rays into UV, visible, or X rays |
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What are the layers of the sun? |
The core The radiation zone The convection zone The photosphere (11,000 degrees) The chromosphere (5 'O' clock shadow) The corona (millions of degrees) |
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What is solar wind? |
The constant flow of energy/ions from the sun |
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What is an Astronomical Unit? |
The distance from the Earth to the Sun 93 million miles |
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What is the Magnetosphere, and what does it create? |
Protects the Earth from harmful UV-C waves and solar wind. Auroras come from the filtering of this solar wind to the poles. The stronger the CME or solar wind, the lower down on the globe the aurora will occur |
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What are the two reasons that sunspots are darker than the rest of the sun? |
1. Cooler (temperature-wise, and socially) 2. Higher magnetism |
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What are solar flares? (Coronal Mass Ejections) |
The magnetic field gets tangled and it breaks, releasing a flare. It takes 16 hours for a flare to hit us. |
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What can we learn from sunspots? |
- How active the sun is - About the "Little Ice Age" (no sunspots for 60 years in the 1600s) -11.2 year sunspot cycle - Magnetic field lines come from sunspots |
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What are auroras, what are they caused by, and what do they cause? |
Auroras are charged particles filtering in to the poles, where it reacts with the atmosphere. The charged particles are known a solar wind, which comes from the sun. Auroras can cause: - Blackouts - Satellite failure (communications down) |
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What are prominences? |
Arcs of gas that follow the magnetic field lines |
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What are binary stars? |
Two stars that orbit each other. |
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Apparent Magnitude |
Ancient Greek classification system for how bright a star is |
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Absolute Magnitude |
The brightness of a star if placed at a distance of 10 parsecs ( 1 parsec = 3.26 light years) negative number : bright positive number : dull |
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Luminosity |
How much energy is released by a star per second. |
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Parallax |
Method to measure how far a star is away Apparent shift of an object due to the change in position of the observer |
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Nebula |
Baby star Just dust and gas cloud in space |
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Protostar |
Dust cloud (nebula) is condensed by gravity, and it gets a hot center |
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Star |
Gravity condenses so much that fusion occurs |
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The mass of a star determines its: |
- Temperature (Bigger = Hotter) - Size - Life cycle - Luminosity (Brightness) - How long it lives |
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What is hydrostatic equilibrium? |
The balance between gravity squeezing inward and pressure from nuclear fusion and radiation pushing outward. The reason why stars are round |
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Red Giant/Super Giant |
- Star burns out its hydrogen - Fusion stops - Gravity condenses the star - Helium begins to fuse into carbon - Star expands because helium fuses super hot - Outer layers turn red, because the outer edges are so far from the core that they cool. |
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What happens after a star becomes a red giant? |
The star is left with a core made of carbon because the helium has been all used up |
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Planetary Nebula |
Leftover core of a red giant. Fusion of helium stops, then the outer layers of the red giant begin to float away because gravity from the core doesn't reach the outer edges. A ball of carbon is left. |
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White Dwarf (Black Dwarf) |
Ball of carbon, size of Earth, very very hot! Black Dwarf is only a theory |
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Supernova |
Fusion stops, gravity then condenses the red giant and it becomes so unstable that the outer edges blow off. Supernovas enrich the universe with heavy elements. |
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Neutron Star |
Gravity condenses the remains into a ball the size of Portsmouth. Spins fast and blinks. |
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Black Hole |
A region in space that has a gravitational field so strong that light can't escape. |
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Compressional Heat |
Increase of pressure = increase of heat Decrease of pressure = decrease of heat Heat generated by overlying material |
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Radioactive Heat |
Isotopes decay - releases heat |
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Accretional Heat |
Heat from meteor bombardment Kinetic energy is transferred into heat |
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Outgassing |
Earth's core creates gas, which rises because it is less dense, pools up underneath the Earth's crust, and is released through volcanoes. Gravity holds the gas in from the volcano and created the atmosphere. |
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Why would you die in the early atmosphere? |
1. No oxygen (until bacteria/algae formed) 2. Air pressure was too high 3. Too hot 4. Air was ammonia-methane (toxic = burn lungs) |
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Where did the water come from? |
1. Comets/Meteors 2. Chemical Reactions 3. Rocks |
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Explain the water world |
It took 600 million years for the atmosphere to cool enough for water to hit the ground, and when it did, it rained for 1000s to millions of years. The massive green ocean was 10,000 feet deep! |
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Explain NGSAPDC |
1. Nebula (dust and gas) 2. Gravity (force of attraction) 3. Sun (accretional disc) 4. Accretion (growth by external sources) 5. ProtoEarth (baby earth) 6. Differentiation (iron & nickel sank - heavy) (silicon & magnesium floated - light) 7. Crust (formed 4.5 bya) |
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Abraham Ortelius |
Dutch mapmaker (1600s) - proposed that the continents had once been together because they looked like puzzle pieces |
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Eduard Suess |
Early 1800s. First to propose the idea of a supercontinent. Named it Gondwanaland. |
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Alfred Wegener |
Australian meteorologist. Published book in 1912 or 1915 called "The Origin of Continents and Oceans." Proposed the continental drift theory. Said the continents were once together and drifted apart - renamed the supercontinent Pangaea (Greek for "All The Earth"). |
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Evidence - Strata |
The strata on the coasts of South America and Africa was the same in its 1. AGE 2. TYPE 3. THICKNESS |
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Evidence - Animal Fossil |
Found two types of the same fossil on each side of the ocean. Could not have evolved the same way so far apart, and couldn't have crossed the ocean because one was a freshwater animal, and the other was a land animal, and neither could have survived the salt water. |
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Evidence - Plant Fossil |
The Glossopteris fern was found every where. Could not have evolved the same way so far apart, and couldn't have crossed the ocean because the seeds were to fragile, and too heavy for the wind to carry. |
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Climate Evidence |
Coal found in Antarctica - Tropical plants form coal, Antarctica must have been closer to the equator. Also, glacial deposits were found in India, Africa, and South America. |
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How did Wegener explain how the continents moved? |
He lost his scientific credibility when he said they 1. Just plowed through the oceans (no marks) 2. Spin of the earth moved them (physics) |
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Arthur Holmes |
1920s - proposed that convection currents move plates |
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Harry Hess |
1950s - proved Holmes' proposal that plates are moved by convection currents in the mantle |
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Sonar and Magnetometers |
Used in the race to map the sea floor. Sonar wasn't as accurate as using a magnetometer, which detects magnetism in rocks |
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Paleomagnetism |
History of Earth's magnetic field found in rocks |
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Isochront |
Layer of same aged/magnetized rock |
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Seafloor Spreading |
States that new ocean crust is being created at ridges, and destroyed at deep sea trenches |
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Ocean/Ocean Divergent |
Ridge Fissure |
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Land/Land Divergent |
ex. Mid Atlantic Ridge |
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Land/Ocean Convergent |
Subduction zone Trench Volcano ex. Ring of Fire |
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Ocecan/Ocean Convergent |
ex. Island Arc, trench |
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Land/ Land Convergent |
Creates big mountains ex. Himalayas |
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Transform Boundary |
Plates slide past each other and they form faults ex. San Andreas Fault |
