GEOL 109 Exam 1 Questions And Correct Verified Answers| Solutions Guaranteed.

Mercury, venus, earth, mars, jupiter, saturn, uranus, neptune - correct answers What is the order of the planets outward from the Sun? There is a big asteroid belt between Mars and Jupiter and another one past neptune - correct answers Where do asteroids and comets fit into this pattern? Inner are dense and full of silicate metals, and outer are bigger and gaseous with icy compositions - correct answers Contrast the inner and the outer planets in terms of relative sizes and compositions. Silicate, metals, hydrogen, gas, ice - correct answers What are the main components that make up the planets? by outer planets - correct answers Where in the Solar System would you find solid bodies with thick layers of water ice? small fragments of other planets, live in an asteroid belt between Mars and jupiter - correct answers asteroids small icy bodies formed in outer solar system - correct answers comets huge ball of gas - correct answers stars large bodies but not large enough to emit nuclear fusion. They orbit a star - correct answers planets orbits a planetary object - correct answers moons Initially only hydrogen (H) and helium (He). Stars form from these light elements. New heavier elements form by fusion in stars - correct answers Describe the events of the Big Bang protons, neutrons, electrons - correct answers constituents of atom Collapse of solar nebula - correct answers How and under what conditions are the elements formed? Where are these conditions met? fusion - correct answers How do the Sun and other stars derive their energy? Occurs near the end of a stars formation. During this phase the star gives up a huge amount of energy which pulls in the magnetic field. It will clear away the loose debris surrounding the nearby planet. - correct answers What happens during the T-Tauri stage of a star's evolution? 1. Gas and dust come together 2. Protostar is formed 3. Main Sequence Star is formed 4. The star becomes a red giant (when it's really really old) - Small stars burning hydrogen and helium become cooler at their surfaces and redder, and consequently are called red giants. These giants may be 10 to 20 times the diameter of their precursor. 5. Planetary Nebula - correct answers Describe the general history and evolution of fusion reactions within a medium-sized star—one that is about the same size as our Sun. By turning into a Planetary Nebula Expands outward and red giant forms. Hydrogen-burning gradually proceeds to the surface, ripping the surface layers away to form a planetary nebula - correct answers How does a medium-sized star die? New stars, dying stars, ejecta, gas, repeat - correct answers What happens to the elements blown away into interstellar space? Hydrogen can burn to form Helium but only at temperature 10 million K - correct answers Under what conditions will hydrogen start to fuse to helium? Carbon (which comes from Helium burned) can combine with other helium nuclei to form oxygen - correct answers How does this compare with the conditions required for helium to fuse to form carbon or oxygen? A supernova explosion - correct answers What marks the death of a large star? They are ejected into space where they may be recycled into new planets, stars, etc. - correct answers What is the fate of elements newly created in a massive star? The lifespan of a smaller or medium sized star (like our sun) is a LOT longer than that of a massive star, because the larger start uses its fuel faster than a smaller star -Billions of years - correct answers Compare the the typical lifetime (in years) of a medium-sized star like our Sun and a large star (~10 times the size of the Sun). Big bang-13.8 billion years ago, accretion of planets-4.5 billion years - correct answers When did the solar system originate? we use meteorites to date the solar system by determining how old the meteorites are and this gives us a good idea of how old the solar system is (Also known as radiometric ages) -Radiometric decay uses elements like uranium, potassium, and rubidium - correct answers How can we date an event that happened so long ago? It's a big collection of dust and gas that collapsed billions of years ago - correct answers Describe the solar nebula from which the planets are thought to have formed. Condensation Aggregation accretion - correct answers How did it evolve from a diffuse nebula into a star with a surrounding hot disk of gas and dust? Scientists think that the solids and gases became physically separate and this happened through the T-Tauri stage. we think that the nebula was swept clean of its uncondensed gases by an appropriately timed T-Tauri phase in the development of the early Sun. - correct answers How was a T-Tauri stage related to the evolution of the nebula? - correct answers Why did planets with compositions as different as those of Earth and Jupiter form from a solar nebula that may have had a uniform chemical composition? - correct answers What happens to a hot gas as it slowly cools? - correct answers Contrast the behavior of volatile and refractory materials. Give an example of each. - correct answers What prevented Mars from obtaining an ice-rich outer shell encasing a rocky interior as the temperature of the nebula continued to drop? - correct answers How did the solids that condensed from the solar nebula accumulate to form large planets? - correct answers What is the evidence for this process? The kinetic energy changed into thermal energy when bodies collide through accretion - correct answers What happened to the kinetic energy of the accreting material as it formed planets? The temperature increases - correct answers What happened to the temperature of a planet as it accreted? Because of the abundance of icy content in the solar nebular - correct answers Why is Jupiter so large? How did its atmosphere originate? accretion is the accumulation of particles into a massive object by gravitationally attracting more gaseous matter in an accretion disk. the planets accreted out of dust and gas left over from the Sun's formation. - correct answers What is accretion, what is the origin of the materials the planets accreted out of, what happened to the left over material? The planets in our solar system accreted about 4.5 billion years ago and once they started it went relatively quickly (only over a few million years) - correct answers when did the planets in our solar system accrete? Between Mars & Jupiter Beyond Neptune - correct answers Where in the solar system did large planets fail to completely accrete The temperature of the planet increases due to the kinetic energy from the collision turning into thermal energy The larger planets had enough gravitational pull that they held onto the light elements (gases) - correct answers What are some of the results of gravitational accretion of the planets? Specifically, describe the surfaces that result and how accretion affected the temperature of a planet Just like someone being punched in the face, a planet being hit hard by a large object will move and become tilted. As a body accretes, the gravity makes the body spherical so one side cannot have more material than another. Other stars are too far away to make a near pass and capture a planet. if a planets spin axis changed with time, all of the planets would be tilted the same amount. - correct answers Why don't all of the planets rotate in the same direction? And why are some of the spin axes not vertical? the outer planets have a lot of Helium in their atmospheres. Their large gravities allows them to hold on to helium even though it is such a light element. They obtained their atmospheres by collapse of nebular gas onto a protoplanet's icy core. The "cores" of the giant planets grew large enough to have enough gravity to hold onto the light elements in the Solar Nebula. There was not degassing, or picking up gas by sweeping around the Solar System, or volatiles condensing onto the planet (because the nebula was already cold at this location. - correct answers The giant planets (Jupiter, Saturn, Uranus, and Neptune) have atmospheres much different than that of Earth. What are some of the important differences, and how did they form? very common bodies that are found by very different types of stars. - correct answers What are exoplanets? Why are so few of those that have been discovered the same size as Earth As mentioned above, the orbits of the gas giants changed dramatically 3.9 billion years ago. The orbits extended farther from the Sun (especially Neptune and Uranus) and the orbits of Neptune and Uranus switched. The inner planets orbits remained unaffected. - correct answers Review the evolution of the orbits of the outer planets and explain the main tenets of the Nice model. How does this orbital reorganization affect the inner planets? Because the planets went through internal differentiation where the planet heated up and then melted to allow for the denser elements to sink to the bottom of the core and the less dense materials to float to the top - correct answers Explain why the rocks found at the surface of a planet, say the Moon, are so different in elemental composition from the meteoritic material from which the planet formed. Silicates: quartz, mica, pyroxene, olivine (Helium, Hydrogen); are denser than ices but less dense than metals Metals: iron, nickel (these are the densest materials) Ices: Water, nitrogen, etc.; are less dense than metals and silicates Atmophile Gases: those that go into the atmosphere - correct answers Contrast the characteristics of silicates, metals, ices, and atmophile gases. Pay special attention to their melting points and densities. High temps, and pressure rocks become weak and behave much like fluids (although they may not be molten). - correct answers Under what conditions can solid rock flow? Would this allow differentiation to occur? -Conduction, convection and radiation are three ways to transfer energy, but here are the different ways planets can be heated: Accretion heating, core formation, radiogenic heating (from radioactive elements decaying), solar energy (an example is the T-Tauri stage of star formation), tidal heating -"If the iron-rich cores thought to exist inside some planets formed by accumulation and gravitational segregation from a once-homogeneous planet, then a tremendous amount of heat must have been released." - correct answers By what processes can a planet become hot? Why is it thought that almost all planets were hot when they formed? "Plasticity allows the transport of materials during planetary differentiation but is largely dependent on a critical temperature within the planet. Therefore planetary differentiation is intimately tied to the thermal history of a planet" - correct answers If a planet begins hot, what process dominates the rest of its thermal history? "If a planet formed hot, an early lithosphere would be thin and mobile and fragments would slide about the slippery asthenosphere below. As the planet cools, its lithosphere thickens and slowly becomes immobile. The link between the thermal evolution of a planet and its surface geologic features is, therefore, the lithosphere." - correct answers How do the thickness and rigidity of the lithosphere of a planet respond to continued cooling? - "Chemical compositions, original temperature distribution, and its accreation history... the size of the planets" -"... the geologic history of a planet is a reflection of its thermal history" - correct answers What are the most important controls on the thermal (heating or cooling) history of a planet? -"Small planets with large surface area to mass ratios cool faster as heat is readily radiated away into space." - smaller planets cool faster -"Large planets will have the highest initial internal temperature and will cool more slowly. So the larger the planet the higher the internal temperature at any given time." - correct answers How does surface area to mass ratio affect a planet's cooling rate?