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<\/p>"},"chapters":[{"params":{"content":[{"content":{"params":{"text":"

Welcome to the Early Earth Tutorial<\/strong>. This resource is designed to be used in full-screen mode with the table of contents always displayed. To set this mode, click the Expand button in the top right of the header AND click the Navigation Menu button in the top left of the header. Then begin making your way through the tutorial by watching the video below.<\/p>\n"},"library":"H5P.AdvancedText 1.1","metadata":{"contentType":"Text","license":"U","title":"Untitled Text"},"subContentId":"8b0dc591-cd35-49f0-b039-5890382fc7f1"},"useSeparator":"auto"},{"content":{"params":{"visuals":{"fit":true,"controls":true},"playback":{"autoplay":false,"loop":false},"l10n":{"name":"Video","loading":"Video player loading...","noPlayers":"Found no video players that supports the given video format.","noSources":"Video is missing sources.","aborted":"Media playback has been aborted.","networkFailure":"Network failure.","cannotDecode":"Unable to decode media.","formatNotSupported":"Video format not supported.","mediaEncrypted":"Media encrypted.","unknownError":"Unknown error.","invalidYtId":"Invalid YouTube ID.","unknownYtId":"Unable to find video with the given YouTube ID.","restrictedYt":"The owner of this video does not allow it to be embedded."},"sources":[{"path":"https:\/\/www.youtube.com\/watch?v=Xrrvzgpr5Y4&t=296s","mime":"video\/YouTube","copyright":{"license":"U"}}]},"library":"H5P.Video 1.6","metadata":{"contentType":"Video","license":"U","title":"Early Earth"},"subContentId":"4d246739-7909-4647-9323-ee2790c63b60"},"useSeparator":"auto"},{"content":{"params":{"panels":[{"content":{"params":{"text":"

[music]
\nAfter having watched the Earth Formation<\/strong> video tutorial, we now have an understanding of how our universe, solar system, and planet formed. But what was early Earth like? How did the rocks we see on the surface form? The atmosphere? The oceans?
\n
\nSince the Earth formed through the collision and accretion of meteorites, studying what meteorites are made of helps us learn what our planet is made of. About \u00bd of the meteorites in our solar system are dense stony-iron and nickel; the other \u00bd are made of less dense carbonaceous materials. Combined together, they represent the total composition of Earth\u2019s rocks: estimated at mass percentages of 31.9% Iron, 29.7% Oxygen, 16.1% Silicon, 15.4% Magnesium. But that composition is very different from what we see on Earth\u2019s surface, which is 47% oxygen, 28% silicon, 8% aluminum, and only 5% iron. Why? Early Earth formed through meteorite accretion would have been homogenous. Present Earth has layers. Where did these layers come from?
\n
\nTo understand the characteristics of early Earth, we need to demonstrate the process of accretion<\/strong>. Take your hands \u2013 hold them as far away from each other as possible. Then bring them together quickly in a loud clap. What do you notice? Are your hands warm? The collision of your hands should have produced a large amount of heat, which causes your hands to sting and be warmer than they were before. Now imagine an early Earth formed by billions of these collisions. The continual bombardment of small asteroids combined with all the previous collisions would have produced so much heat that early Earth would have been almost entirely molten. In such a state, the material would have separated by density<\/strong>.
\n
\nThe denser materials (most of the iron) would have sunk to the center to form Earth\u2019s innermost layer known as the core<\/strong>. The less dense material would have risen to the top to form the outer surface layer known as the crust <\/strong>(mostly aluminum silicates). The remainder sits between and is known as the mantle<\/strong>. A similar process happens when we put chocolate and marshmallows in water \u2013 the marshmallows are less dense and float on top. The chocolate is more dense and sinks to the bottom. The water sits in the middle. Through density separation we form Earth\u2019s three compositional layers \u2013 the crust, the mantle, and the core. When did that happen? With early Earth mostly molten, it would have all happened within a few million years at most \u2013 so basically concurrent with Earth\u2019s formation \u2013 4.6 billion years ago.
\n
\nSo what? Why is it important that Earth has layers? How does that affect us? First, let\u2019s look closer at the core, which is composed of two parts \u2013 the liquid iron outer core<\/strong>, and the solid iron inner core<\/strong>. Both of them are under high pressure and are very hot. As you know from heating water in a pot on a stove, hot fluids will convect <\/strong>\u2013 the hotter bits at the bottom expand and become less dense, rising above the cooler denser material around them. This constant overturning or cycling is an excellent method for transferring heat. However, if the convecting material is a hot, liquid metal, the convection will also produce a magnetic field. So forming layers on the earth also led to the formation of a magnetic field<\/strong>. This magnetic field successfully deflected the early Sun\u2019s fierce, hot winds, allowing gases that were bubbling up out of the molten earth to begin accumulating on Earth\u2019s surface. Prior to the magnetic field formation, any gases would have been stripped away and blown to the outer solar system. 4.6-billion-year-old Earth had no atmosphere. However, once its layers formed, it did. Another important layer that formed was a plastic portion of the mantle, called the asthenosphere, that starts about 100 km below the surface and that, like the outer core, also convects. Plastic means that while the asthenosphere is, technically, considered solid, it behaves like silly putty and is capable of flow over long periods of time. Thus it can convect, and convection of this slow-flowing plastic asthenosphere causes the more rigid section of Earth that sits above it, called the lithosphere<\/strong>, to break into pieces, which we call plates<\/strong>. These plates are pushed around by the convection currents underneath them and produce a surface-altering process known as Plate Tectonics<\/strong>. We\u2019ll address both these processes \u2013- the magnetic field and Plate Tectonics \u2013 in future video tutorials.
\n
\nPause now. [music]
\n
\nWith a magnetic field now deflecting solar winds, Earth\u2019s atmosphere started to collect. What was the source of the gases that collected? The molten Earth \u2013 with gases bubbling up from the molten rock. Once the earth\u2019s surface cooled enough to create a solid surface. these gases continued to erupt from volcanoes. Volcanoes are a major source of gases like water, carbon dioxide, and sulfur dioxide. Gases also entered the newly growing atmosphere from comets colliding with Earth. As we reviewed in the Earth Formation video tutorial, comets contain water, ammonia, and carbon dioxide.
\n
\nHere is an artist\u2019s rendition of what early Earth would have looked like with cometary and asteroid collisions and erupting volcanoes on a mostly molten surface.
\n
\nLet\u2019s look closer at early earth\u2019s atmosphere, which was hot and toxic. Its primary ingredient was carbon dioxide, but it also contained small amounts of sulfurous compounds, carbon monoxide, methane, and cyanide. Let\u2019s compare early earth\u2019s atmosphere with the atmospheres of other rocky planets in our solar system today. The three rocky planets with atmospheres (Mercury has no atmosphere) show two very similar atmosphere and one very different one \u2013 Earth\u2019s. Venus and Mars both have carbon dioxide as the major atmospheric gas, much like Earth\u2019s early atmosphere, followed by nitrogen and argon. Notice the lack of any oxygen. Why is Earth\u2019s atmosphere today so different than it was originally and so different than the other two rocky planets that are its neighbors??
\n
\nFirst, as the early Earth lost some of its initial heat of formation and cooled, not only did the surface crust harden, but it also allowed the water present in the early atmosphere to cool enough for it to rain down and cover the hard crust with oceans. These early rains would have removed most of the water from the atmosphere, leaving it, like today, as only 1-4% by mass, depending on the climate. What happens next? Water is a giant absorber for carbon dioxide (we say that carbon dioxide is highly soluble in water), so once the oceans formed, much of the carbon dioxide in the atmosphere would have dissolved into it. We take advantage of the high solubility of carbon dioxide today when we use it to carbonate beverages.
\n
\nThe oldest evidence we have of liquid oceans on the surface of the Earth is from 4.4 billion years ago. What is that evidence? Scientists found and dated 4.4-billion-year-old crystals in rocks in Australia \u2013 these crystals, called zircons<\/strong>, are grains that collected on a beach long ago. The original rock that contained these zircons and then weathered leaving them behind is itself long gone. But the rock that formed from cementing the old beach grains, a beach sandstone, is still on Earth\u2019s surface. Not only do these ancient zircon grains indicate the presence of solid rock on Earth\u2019s surface 4.4 billion years ago, but they also retain isotopic evidence of liquid water. The ratio of isotopes we see in the Uranium (*error: should be Oxygen)<\/strong><\/em> atoms in the crystal are ratios known only to occur in the presence of liquid water.
\n
\nThe formation of oceans explains where the water and most of the carbon dioxide went in Earth\u2019s early atmosphere, but where did the rest of the carbon dioxide go and what formed the oxygen? The rest of this mystery is resolved when we review the impact of life on our planet. To learn more, continue to the video tutorial, Life on Earth<\/strong>.
\n
\nPause now. [music]
\n
\nFor more information and more detail, continue on to the next video in this series. [music]
\n
\n[end credits]
\n
\nEarth Formation Series:
\nPart I: Earth Formation
\nPart II: Radiometric Dating
\nPart III: Density
\nPart IV: Early Earth
\nPart V: Life on Earth
\n <\/p>\n\n

Early Earth Produced by Katryn Wiese
\nCopyright: Creative Commons Attribution-NonCommercial-ShareAlike 3.0
\n
\nAll media produced by Katryn Wiese unless indicated below:
\n*Intro and exit music: used with permission (c) Alexis Harte (www.alexisharte.com)
\n*Early Earth - Artist\u2019s Rendition: Used with permission. Copyright: Julian Baum\/Take 27 Ltd
\n*Hoba Meteorite. CC-BY-2.5. Attribution: Calips.
\n*Murchison Meteorite. CC BY-SA 3.0. Attribution: Basilicofesco
\n*Kilauea Eruption -- USGS -- J.D. Griggs.
\n*Boiling Water. Creative Commons: CC BY-SA 3.0 -- Attribution: Gran
\n*Convecting Outer Core -- NA Smithsonian Institution -- Public Domain.
\n*Earth's magnetosphere with solar winds. NASA. Public Domain.
\n*Artist's rendition of early Earth with volcanoes -- artist unknown
\n*Cooling and crust-hardening early Earth \u2013 artist unknown
\n*Rain on water: Creative Commons. Flikr: snoboard1010
\n*Jack Hills Satellite and above-earth photos -- NASA -- Public Domain
\n*Jack Hills Outcrop: Copyright: Bruce Watson, Rensselaer.
\n*Jack Hills Zircon: Copyright: John Valley, University of Wisconsin.<\/p>\n"},"library":"H5P.AdvancedText 1.1","metadata":{"contentType":"Text","license":"U","title":"Untitled Text"},"subContentId":"4ad4c511-02a6-4715-a0d9-3ffda6cb6dd5"},"title":"Early Earth Video Script (for review as needed)"}],"hTag":"h2"},"library":"H5P.Accordion 1.0","metadata":{"contentType":"Accordion","license":"U","title":"Early Earth Video Script (for review as needed)"},"subContentId":"a9f1f996-17cc-4df2-a654-62079e1f0762"},"useSeparator":"enabled"},{"content":{"params":{"text":"

When done with the video above, continue through the remaining pages of this book to review content and images from the video, explore some content more deeply, and test your understanding through interactive ungraded quiz questions. The final page of the tutorial is a list of Additional Resources for students who want to dig even deeper into some of the video contents. When you've reached that page, you're done.<\/p>\n\n

To navigate to the remaining pages of this tutorial, use the arrow keys that appear in the header and footer. Or use the table of contents navigation menu, which you can toggle open or closed by using the button on the top left of the screen. <\/p>\n"},"library":"H5P.AdvancedText 1.1","metadata":{"contentType":"Text","license":"U","title":"Untitled Text"},"subContentId":"a3bb8319-4661-4722-9ffc-c38a2593d402"},"useSeparator":"enabled"}]},"library":"H5P.Column 1.18","subContentId":"d7bf0253-f2f2-423c-a80e-6146a7588f15","metadata":{"contentType":"Column","license":"CC BY-NC-SA","title":"Video: Early Earth","authors":[{"name":"8b018338-7f16-4014-95b4-f2617edc8531","role":"Author"}],"licenseVersion":"4.0"}},{"params":{"content":[{"content":{"params":{"decorative":false,"contentName":"Image","alt":"Scaled timeline of solar system and Earth formation","expandImage":"Expand Image","minimizeImage":"Minimize Image","file":{"path":"images\/file-65ed20adc7533.jpg","mime":"image\/jpeg","copyright":{"license":"U"},"width":2402,"height":2154}},"library":"H5P.Image 1.1","metadata":{"contentType":"Image","license":"U","title":"Untitled Image"},"subContentId":"a8c51341-b6a8-47d8-b42e-5f8337357929"},"useSeparator":"auto"},{"content":{"params":{"text":"

The figure above is a scaled timeline of the history of the Universe from 13.8 Ga to today.<\/span><\/span><\/em><\/p>\n"},"library":"H5P.AdvancedText 1.1","metadata":{"contentType":"Text","license":"U","title":"Untitled Text"},"subContentId":"165181be-bf22-495b-a570-0e548884d520"},"useSeparator":"auto"}]},"library":"H5P.Column 1.18","metadata":{"contentType":"Column","license":"U","title":"Scaled Timeline"},"subContentId":"fac80f08-e97f-4a40-8c02-c236bae504f9"},{"params":{"content":[{"content":{"params":{"text":"

\n
To review this history, scroll to the bottom of the page and start there. Read from the bottom up!<\/strong>
\nGa<\/span><\/span><\/span><\/strong> = Giga annum = billion years ago<\/span><\/span><\/span><\/span><\/span><\/p>\n"},"library":"H5P.AdvancedText 1.1","metadata":{"contentType":"Text","license":"U","title":"Untitled Text"},"subContentId":"3a60e83f-ae10-41a0-882d-f6451aa4e7de"},"useSeparator":"auto"},{"content":{"params":{"text":"
\n\t
3.85 Ga<\/strong> -- Earliest evidence of microbial activity (carbon isotope ratios). This early life likely lived in the oceans where they were hidden from the sun\u2019s ultraviolet rays (no ozone layer yet, because no oxygen in the atmosphere). These early bacteria were known as prokaryotes: single celled organisms with no nucleus, otherwise known as bacteria. These early life forms were likely chemosynthetic, making food from energy derived from gases emitted at hydrothermal vents on the bottom of the seafloor.<\/span><\/span><\/li>\n\t
4.4 Ga <\/strong>-- Earth\u2019s surface cools enough for a solid crust to form. Earth\u2019s atmosphere (accumulated gases from volcanic outgassing and comets) contains (in decreasing order) carbon dioxide, nitrogen, water vapor, methane, ammonia, carbon monoxide, sulfur dioxide, hydrogen sulfide, and hydrogen cyanide. Because of the solid cooler surface conditions, much of the atmospheric water now rains down and fills in basins to form the first oceans. <\/span><\/span><\/li>\n\t
4.5 Ga<\/strong> -- A Mars-sized object crashes into Earth creating debris that ends up in orbit around the Earth, eventually coalescing through accretion to form the Moon.<\/span><\/span><\/li>\n\t
4.6 Ga<\/strong> -- <\/span><\/span> As the solar disk cools down, orbiting material collides and clumps to form larger objects (accretion). Continued accretion led to larger bodies with higher gravity that swept up more material within their orbits and ultimately became planets. Not all the material got swept up in this process. A large belt of leftover rocky debris \u2013 asteroids \u2013 exists between Mars and Jupiter. A belt of leftover icy debris \u2013 comets \u2013 orbits in the outer solar system.At this point, the interior of the Earth is mostly molten from the heat of accretion. Density stratification occurs: dense material, like iron, sinks to form the core while less dense material rises to form the crust; the remainder becomes the mantle layer. All planets are hot from the accretion process. Volcanic activity and continual meteorite collisions dominate the surface. Gases from volcanoes and comets form an early, hot, toxic, atmosphere.<\/li>\n<\/ul>\n\n
\n
What effect did radioactivity have in the first billion years of Earth?<\/strong><\/p>\n\n
Radioactive decay of elements inside Earth, like particular isotopes of Uranium and Carbon, produces a lot of heat. That heat builds up inside the Earth and keeps the Earth's interior HOT. If there were no radioactive decay, Earth's interior would have cooled substantially by now and there probably wouldn't be a molten outer core. But for every calorie of heat the Earth loses through convection and conduction and radiation, a bit more is created by radioactive decay, so for every 3 steps forward, it takes 2 steps back, and that delays considerably the cooling of Earth's interior. (It IS cooling, just very very slowly.)<\/p>\n"},"library":"H5P.AdvancedText 1.1","metadata":{"contentType":"Text","license":"U","title":"Untitled Text"},"subContentId":"6b5a0946-0742-46bf-b20b-fd274e61911e"},"useSeparator":"auto"},{"content":{"params":{"introPage":{"showIntroPage":false,"startButtonText":"Start Quiz","introduction":""},"progressType":"dots","passPercentage":100,"questions":[{"params":{"media":{"disableImageZooming":false},"answers":[{"correct":true,"tipsAndFeedback":{"tip":"","chosenFeedback":"","notChosenFeedback":""},"text":"
4.6 Ga<\/div>\n"},{"correct":false,"tipsAndFeedback":{"tip":"","chosenFeedback":"","notChosenFeedback":""},"text":"
4.4 Ga<\/div>\n"},{"correct":false,"tipsAndFeedback":{"tip":"","chosenFeedback":"","notChosenFeedback":""},"text":"
4.0 Ga<\/div>\n"},{"correct":false,"tipsAndFeedback":{"tip":"","chosenFeedback":"","notChosenFeedback":""},"text":"
3.85 Ga<\/div>\n"},{"correct":false,"tipsAndFeedback":{"tip":"","chosenFeedback":"","notChosenFeedback":""},"text":"
3.5 Ga<\/div>\n"}],"overallFeedback":[{"from":0,"to":100}],"behaviour":{"enableRetry":true,"enableSolutionsButton":false,"enableCheckButton":true,"type":"auto","singlePoint":false,"randomAnswers":false,"showSolutionsRequiresInput":true,"confirmCheckDialog":false,"confirmRetryDialog":false,"autoCheck":false,"passPercentage":100,"showScorePoints":true},"UI":{"checkAnswerButton":"Check","submitAnswerButton":"Submit","showSolutionButton":"Show solution","tryAgainButton":"Retry","tipsLabel":"Show tip","scoreBarLabel":"You got :num out of :total points","tipAvailable":"Tip available","feedbackAvailable":"Feedback available","readFeedback":"Read feedback","wrongAnswer":"Wrong answer","correctAnswer":"Correct answer","shouldCheck":"Should have been checked","shouldNotCheck":"Should not have been checked","noInput":"Please answer before viewing the solution","a11yCheck":"Check the answers. The responses will be marked as correct, incorrect, or unanswered.","a11yShowSolution":"Show the solution. The task will be marked with its correct solution.","a11yRetry":"Retry the task. Reset all responses and start the task over again."},"confirmCheck":{"header":"Finish ?","body":"Are you sure you wish to finish ?","cancelLabel":"Cancel","confirmLabel":"Finish"},"confirmRetry":{"header":"Retry ?","body":"Are you sure you wish to retry ?","cancelLabel":"Cancel","confirmLabel":"Confirm"},"question":"
When did gases <\/strong>start collecting and building Earth's atmosphere?<\/p>\n"},"library":"H5P.MultiChoice 1.16","metadata":{"contentType":"Multiple Choice","license":"U","title":"Gas collection"},"subContentId":"6ae16748-7985-4c9e-9385-37afeb474886"},{"params":{"media":{"disableImageZooming":false},"answers":[{"correct":false,"tipsAndFeedback":{"tip":"","chosenFeedback":"","notChosenFeedback":""},"text":"
Asteroids<\/div>\n"},{"correct":true,"tipsAndFeedback":{"tip":"","chosenFeedback":"","notChosenFeedback":""},"text":"
Comets<\/div>\n"},{"correct":false,"tipsAndFeedback":{"tip":"","chosenFeedback":"","notChosenFeedback":""},"text":"
Original nebula debris that collided to form Earth<\/div>\n"},{"correct":true,"tipsAndFeedback":{"tip":"","chosenFeedback":"","notChosenFeedback":""},"text":"
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Which of the following were sources of water <\/strong>to Earth's early atmosphere? (Choose all that apply.)<\/p>\n"},"library":"H5P.MultiChoice 1.16","metadata":{"contentType":"Multiple Choice","license":"U","title":"Earth water"},"subContentId":"094857c4-d5db-419c-a558-29ae1ae1cb36"},{"params":{"media":{"disableImageZooming":false},"answers":[{"correct":false,"tipsAndFeedback":{"tip":"","chosenFeedback":"","notChosenFeedback":""},"text":"
4.6 Ga<\/div>\n"},{"correct":true,"tipsAndFeedback":{"tip":"","chosenFeedback":"","notChosenFeedback":""},"text":"
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3.85 Ga<\/div>\n"},{"correct":false,"tipsAndFeedback":{"tip":"","chosenFeedback":"","notChosenFeedback":""},"text":"
3.5 Ga<\/div>\n"}],"overallFeedback":[{"from":0,"to":100}],"behaviour":{"enableRetry":true,"enableSolutionsButton":false,"enableCheckButton":true,"type":"auto","singlePoint":false,"randomAnswers":false,"showSolutionsRequiresInput":true,"confirmCheckDialog":false,"confirmRetryDialog":false,"autoCheck":false,"passPercentage":100,"showScorePoints":true},"UI":{"checkAnswerButton":"Check","submitAnswerButton":"Submit","showSolutionButton":"Show solution","tryAgainButton":"Retry","tipsLabel":"Show tip","scoreBarLabel":"You got :num out of :total points","tipAvailable":"Tip available","feedbackAvailable":"Feedback available","readFeedback":"Read feedback","wrongAnswer":"Wrong answer","correctAnswer":"Correct answer","shouldCheck":"Should have been checked","shouldNotCheck":"Should not have been checked","noInput":"Please answer before viewing the solution","a11yCheck":"Check the answers. The responses will be marked as correct, incorrect, or unanswered.","a11yShowSolution":"Show the solution. The task will be marked with its correct solution.","a11yRetry":"Retry the task. Reset all responses and start the task over again."},"confirmCheck":{"header":"Finish ?","body":"Are you sure you wish to finish ?","cancelLabel":"Cancel","confirmLabel":"Finish"},"confirmRetry":{"header":"Retry ?","body":"Are you sure you wish to retry ?","cancelLabel":"Cancel","confirmLabel":"Confirm"},"question":"
When did first oceans<\/strong> form? (time when planet cooled enough and water in atmosphere finally rained down and soaked up a lot of the carbon dioxide):<\/p>\n"},"library":"H5P.MultiChoice 1.16","metadata":{"contentType":"Multiple Choice","license":"U","title":"Ocean formation"},"subContentId":"9891b8dd-0190-4b7a-92fc-036c934ec461"}],"disableBackwardsNavigation":false,"randomQuestions":false,"endGame":{"showResultPage":true,"showSolutionButton":false,"showRetryButton":true,"noResultMessage":"Finished","message":"Your result:","scoreBarLabel":"You got @finals out of @totals points","overallFeedback":[{"from":0,"to":100}],"solutionButtonText":"Show solution","retryButtonText":"Retry","finishButtonText":"Finish","submitButtonText":"Submit","showAnimations":false,"skippable":false,"skipButtonText":"Skip video"},"texts":{"prevButton":"Previous question","nextButton":"Next question","finishButton":"Finish","submitButton":"Submit","textualProgress":"Question: @current of @total questions","jumpToQuestion":"Question %d of %total","questionLabel":"Question","readSpeakerProgress":"Question @current of @total","unansweredText":"Unanswered","answeredText":"Answered","currentQuestionText":"Current question","navigationLabel":"Questions"},"override":{"checkButton":true,"showSolutionButton":"off","retryButton":"on"}},"library":"H5P.QuestionSet 1.20","metadata":{"contentType":"Question Set","license":"U","title":"Test Your Understanding"},"subContentId":"fcf9275c-d3d2-4ba1-95f9-a8e87eee7375"},"useSeparator":"auto"}]},"library":"H5P.Column 1.18","metadata":{"contentType":"Column","license":"U","title":"Brief History of Earth"},"subContentId":"ee7c5ca8-c5ba-41b1-bc0c-021efe2762b4"},{"params":{"content":[{"content":{"params":{"decorative":false,"contentName":"Image","file":{"path":"images\/file-62b75285af11b.jpg","mime":"image\/jpeg","copyright":{"license":"U"},"width":3544,"height":2138},"alt":"Earth's Layers","expandImage":"Expand Image","minimizeImage":"Minimize Image","title":"Earth's Layers"},"library":"H5P.Image 1.1","metadata":{"contentType":"Image","license":"U","title":"Untitled Image"},"subContentId":"b23e2c98-eeff-47a6-ba91-d2c38458cc67"},"useSeparator":"auto"},{"content":{"params":{"text":"
Above figure: Cross-section of Earth showing its layers (to scale, except for greatly exaggerated crust) Note: the MOHO is the name given to the boundary between the crust and the mantle.<\/em><\/p>
"},"library":"H5P.AdvancedText 1.1","metadata":{"contentType":"Text","license":"U","title":"Untitled Text"},"subContentId":"5ea71c35-5d00-4834-950b-527d087dbd68"},"useSeparator":"auto"},{"content":{"params":{"text":"
Earth's main layers<\/strong><\/div>\n\n
\n\n\t\n\t\t\n\t\t\t\n\t\t\n\t\t\t\n\t\t\t\n\t\t\t\n\t\t\t\n\t\t\t
Layers<\/strong><\/th>\n\t\t\t Thickness<\/strong><\/th>\n\t\t\t Composition<\/strong><\/th>\n\t\t\t Density\/State<\/strong><\/th>\n\t\t<\/tr>\n\t<\/thead>\n\t
Crust: Oceanic <\/span><\/span><\/strong><\/td>\n\t\t\t 3-10 km<\/td>\n\t\t\t Si, O, Fe, Mg, Al = Basalt<\/span><\/span><\/em><\/td>\n\t\t\t 2.9 g\/cc SOLID<\/td>\n\t\t<\/tr>\n\t\t
Crust: Continental<\/span><\/span><\/strong><\/td>\n\t\t\t 30-50 km<\/td>\n\t\t\t Si, O, Al = Granite<\/span><\/span><\/td>\n\t\t\t 2.7 g\/cc SOLID<\/td>\n\t\t<\/tr>\n\t\t
Mantle<\/strong><\/td>\n\t\t\t 2900 km<\/td>\n\t\t\t Mg, Fe, Si, O<\/span><\/span><\/td>\n\t\t\t 4.5 g\/cc SOLID<\/td>\n\t\t<\/tr>\n\t\t
Outer core<\/strong><\/td>\n\t\t\t 2200 km<\/td>\n\t\t\t Fe, Ni (S, Si)<\/td>\n\t\t\t 11 g\/cc LIQUID<\/td>\n\t\t<\/tr>\n\t\t
Inner core<\/strong><\/td>\n\t\t\t 1300 km<\/td>\n\t\t\t Fe, Ni (S, Si)<\/td>\n\t\t\t 16 g\/cc SOLID<\/td>\n\t\t<\/tr>\n\t<\/tbody>\n<\/table>\n\n
<\/div>\n\n
<\/div>\n<\/div>\n
<\/div>"},"library":"H5P.Table 1.2","metadata":{"contentType":"Table","license":"U","title":"Earth's Layers"},"subContentId":"079f1d08-edba-42e6-a060-268d7575cfbb"},"useSeparator":"auto"},{"content":{"params":{"text":"
From the video: <\/p>
\"The continual bombardment of small asteroids combined with all the previous collisions would have produced so much heat that early Earth would have been almost entirely molten. In such a state, the material would have separated by density<\/strong>.

The denser materials (most of the iron) would have sunk to the center to form Earth\u2019s innermost layer known as the core<\/strong>. The less dense material would have risen to the top to form the outer surface layer known as the crust <\/strong>(mostly aluminum silicates). The remainder sits between and is known as the mantle<\/strong>. A similar process happens when we put chocolate and marshmallows in water \u2013 the marshmallows are less dense and float on top. The chocolate is more dense and sinks to the bottom. The water sits in the middle. Through density separation we form Earth\u2019s three compositional layers \u2013 the crust, the mantle, and the core. When did that happen? With early Earth mostly molten, it would have all happened within a few million years at most \u2013 so basically concurrent with Earth\u2019s formation \u2013 4.6 billion years ago.

So what? Why is it important that Earth has layers? How does that affect us? First, let\u2019s look closer at the core, which is composed of two parts \u2013 the liquid iron outer core<\/strong>, and the solid iron inner core<\/strong>. Both of them are under high pressure and are very hot. As you know from heating water in a pot on a stove, hot fluids will convect <\/strong>\u2013 the hotter bits at the bottom expand and become less dense, rising above the cooler denser material around them. This constant overturning or cycling is an excellent method for transferring heat. However, if the convecting material is a hot, liquid metal, the convection will also produce a magnetic field<\/strong>. So forming layers on the earth also led to the formation of a magnetic field. This magnetic field successfully deflected the early Sun\u2019s fierce, hot winds, allowing gases that were bubbling up out of the molten earth to begin accumulating on Earth\u2019s surface. Prior to the magnetic field formation, any gases would have been stripped away and blown to the outer solar system. 4.6-billion-year-old Earth had no atmosphere. However, once its layers formed, it did. Another important layer that formed was a plastic portion of the mantle, called the asthenosphere<\/strong>, that starts about 100 km below the surface and that, like the outer core, also convects. Plastic means that while the asthenosphere is, technically, considered solid, it behaves like silly putty and is capable of flow over long periods of time. Thus it can convect, and convection of this slow-flowing plastic asthenosphere causes the more rigid section of Earth that sits above it, called the lithosphere<\/strong>, to break into pieces, which we call plates. These plates are pushed around by the convection currents underneath them and produce a surface-altering process known as Plate Tectonics<\/strong>. We\u2019ll address both these processes \u2013- the magnetic field and Plate Tectonics \u2013 in future video tutorials.\"<\/p>"},"library":"H5P.AdvancedText 1.1","metadata":{"contentType":"Text","license":"U","title":"Untitled Text"},"subContentId":"402007e6-e97f-4ebf-8b0a-40bcf71ad674"},"useSeparator":"auto"},{"content":{"params":{"introPage":{"showIntroPage":false,"startButtonText":"Start Quiz","introduction":""},"progressType":"dots","passPercentage":100,"questions":[{"params":{"media":{"disableImageZooming":false},"answers":[{"correct":false,"tipsAndFeedback":{"tip":"","chosenFeedback":"","notChosenFeedback":""},"text":"
Accretion<\/div>\n"},{"correct":false,"tipsAndFeedback":{"tip":"","chosenFeedback":"","notChosenFeedback":""},"text":"
Collision<\/div>\n"},{"correct":true,"tipsAndFeedback":{"tip":"","chosenFeedback":"","notChosenFeedback":""},"text":"
Density separation<\/div>\n"},{"correct":false,"tipsAndFeedback":{"tip":"","chosenFeedback":"","notChosenFeedback":""},"text":"
Photosynthesis<\/div>\n"}],"overallFeedback":[{"from":0,"to":100}],"behaviour":{"enableRetry":true,"enableSolutionsButton":false,"enableCheckButton":true,"type":"auto","singlePoint":false,"randomAnswers":false,"showSolutionsRequiresInput":true,"confirmCheckDialog":false,"confirmRetryDialog":false,"autoCheck":false,"passPercentage":100,"showScorePoints":true},"UI":{"checkAnswerButton":"Check","submitAnswerButton":"Submit","showSolutionButton":"Show solution","tryAgainButton":"Retry","tipsLabel":"Show tip","scoreBarLabel":"You got :num out of :total points","tipAvailable":"Tip available","feedbackAvailable":"Feedback available","readFeedback":"Read feedback","wrongAnswer":"Wrong answer","correctAnswer":"Correct answer","shouldCheck":"Should have been checked","shouldNotCheck":"Should not have been checked","noInput":"Please answer before viewing the solution","a11yCheck":"Check the answers. The responses will be marked as correct, incorrect, or unanswered.","a11yShowSolution":"Show the solution. The task will be marked with its correct solution.","a11yRetry":"Retry the task. Reset all responses and start the task over again."},"confirmCheck":{"header":"Finish ?","body":"Are you sure you wish to finish ?","cancelLabel":"Cancel","confirmLabel":"Finish"},"confirmRetry":{"header":"Retry ?","body":"Are you sure you wish to retry ?","cancelLabel":"Cancel","confirmLabel":"Confirm"},"question":"
Which of the following processes formed Earth's layers?<\/p>\n"},"library":"H5P.MultiChoice 1.16","metadata":{"contentType":"Multiple Choice","license":"U","title":"Which of the following processes formed Earth's layers?"},"subContentId":"8b64affc-206a-48b9-b06b-cd33c1d597f1"},{"params":{"media":{"disableImageZooming":false},"answers":[{"correct":false,"tipsAndFeedback":{"tip":"","chosenFeedback":"","notChosenFeedback":""},"text":"
Crust<\/div>\n"},{"correct":false,"tipsAndFeedback":{"tip":"","chosenFeedback":"","notChosenFeedback":""},"text":"
Inner core<\/div>\n"},{"correct":false,"tipsAndFeedback":{"tip":"","chosenFeedback":"","notChosenFeedback":""},"text":"
Mantle<\/div>\n"},{"correct":true,"tipsAndFeedback":{"tip":"","chosenFeedback":"","notChosenFeedback":""},"text":"
Outer core<\/div>\n"}],"overallFeedback":[{"from":0,"to":100}],"behaviour":{"enableRetry":true,"enableSolutionsButton":false,"enableCheckButton":true,"type":"auto","singlePoint":false,"randomAnswers":false,"showSolutionsRequiresInput":true,"confirmCheckDialog":false,"confirmRetryDialog":false,"autoCheck":false,"passPercentage":100,"showScorePoints":true},"UI":{"checkAnswerButton":"Check","submitAnswerButton":"Submit","showSolutionButton":"Show solution","tryAgainButton":"Retry","tipsLabel":"Show tip","scoreBarLabel":"You got :num out of :total points","tipAvailable":"Tip available","feedbackAvailable":"Feedback available","readFeedback":"Read feedback","wrongAnswer":"Wrong answer","correctAnswer":"Correct answer","shouldCheck":"Should have been checked","shouldNotCheck":"Should not have been checked","noInput":"Please answer before viewing the solution","a11yCheck":"Check the answers. The responses will be marked as correct, incorrect, or unanswered.","a11yShowSolution":"Show the solution. The task will be marked with its correct solution.","a11yRetry":"Retry the task. Reset all responses and start the task over again."},"confirmCheck":{"header":"Finish ?","body":"Are you sure you wish to finish ?","cancelLabel":"Cancel","confirmLabel":"Finish"},"confirmRetry":{"header":"Retry ?","body":"Are you sure you wish to retry ?","cancelLabel":"Cancel","confirmLabel":"Confirm"},"question":"
Which major Earth layer is liquid?<\/p>\n"},"library":"H5P.MultiChoice 1.16","metadata":{"contentType":"Multiple Choice","license":"U","title":"Untitled Multiple Choice"},"subContentId":"07e4ba1a-2455-49af-ae10-5a60c5c7fa22"},{"params":{"media":{"disableImageZooming":false},"answers":[{"correct":false,"tipsAndFeedback":{"tip":"","chosenFeedback":"","notChosenFeedback":""},"text":"
Crust<\/div>\n"},{"correct":true,"tipsAndFeedback":{"tip":"","chosenFeedback":"","notChosenFeedback":""},"text":"
Inner core<\/div>\n"},{"correct":false,"tipsAndFeedback":{"tip":"","chosenFeedback":"","notChosenFeedback":""},"text":"
Mantle<\/div>\n"},{"correct":true,"tipsAndFeedback":{"tip":"","chosenFeedback":"","notChosenFeedback":""},"text":"
Outer core<\/div>\n"}],"overallFeedback":[{"from":0,"to":100}],"behaviour":{"enableRetry":true,"enableSolutionsButton":false,"enableCheckButton":true,"type":"auto","singlePoint":false,"randomAnswers":false,"showSolutionsRequiresInput":true,"confirmCheckDialog":false,"confirmRetryDialog":false,"autoCheck":false,"passPercentage":100,"showScorePoints":true},"UI":{"checkAnswerButton":"Check","submitAnswerButton":"Submit","showSolutionButton":"Show solution","tryAgainButton":"Retry","tipsLabel":"Show tip","scoreBarLabel":"You got :num out of :total points","tipAvailable":"Tip available","feedbackAvailable":"Feedback available","readFeedback":"Read feedback","wrongAnswer":"Wrong answer","correctAnswer":"Correct answer","shouldCheck":"Should have been checked","shouldNotCheck":"Should not have been checked","noInput":"Please answer before viewing the solution","a11yCheck":"Check the answers. The responses will be marked as correct, incorrect, or unanswered.","a11yShowSolution":"Show the solution. The task will be marked with its correct solution.","a11yRetry":"Retry the task. Reset all responses and start the task over again."},"confirmCheck":{"header":"Finish ?","body":"Are you sure you wish to finish ?","cancelLabel":"Cancel","confirmLabel":"Finish"},"confirmRetry":{"header":"Retry ?","body":"Are you sure you wish to retry ?","cancelLabel":"Cancel","confirmLabel":"Confirm"},"question":"
Which Earth layer(s) are made almost entirely of iron? Choose all that apply.<\/p>\n"},"library":"H5P.MultiChoice 1.16","metadata":{"contentType":"Multiple Choice","license":"U","title":"Untitled Multiple Choice"},"subContentId":"3cc6296d-a304-4b2b-8ae2-68971f34aeb7"},{"params":{"media":{"disableImageZooming":false},"answers":[{"correct":false,"tipsAndFeedback":{"tip":"","chosenFeedback":"","notChosenFeedback":""},"text":"
Crust<\/div>\n"},{"correct":true,"tipsAndFeedback":{"tip":"","chosenFeedback":"","notChosenFeedback":""},"text":"
Inner core<\/div>\n"},{"correct":false,"tipsAndFeedback":{"tip":"","chosenFeedback":"","notChosenFeedback":""},"text":"
Mantle<\/div>\n"},{"correct":false,"tipsAndFeedback":{"tip":"","chosenFeedback":"","notChosenFeedback":""},"text":"
Outer core<\/div>\n"}],"overallFeedback":[{"from":0,"to":100}],"behaviour":{"enableRetry":true,"enableSolutionsButton":false,"enableCheckButton":true,"type":"auto","singlePoint":false,"randomAnswers":false,"showSolutionsRequiresInput":true,"confirmCheckDialog":false,"confirmRetryDialog":false,"autoCheck":false,"passPercentage":100,"showScorePoints":true},"UI":{"checkAnswerButton":"Check","submitAnswerButton":"Submit","showSolutionButton":"Show solution","tryAgainButton":"Retry","tipsLabel":"Show tip","scoreBarLabel":"You got :num out of :total points","tipAvailable":"Tip available","feedbackAvailable":"Feedback available","readFeedback":"Read feedback","wrongAnswer":"Wrong answer","correctAnswer":"Correct answer","shouldCheck":"Should have been checked","shouldNotCheck":"Should not have been checked","noInput":"Please answer before viewing the solution","a11yCheck":"Check the answers. The responses will be marked as correct, incorrect, or unanswered.","a11yShowSolution":"Show the solution. The task will be marked with its correct solution.","a11yRetry":"Retry the task. Reset all responses and start the task over again."},"confirmCheck":{"header":"Finish ?","body":"Are you sure you wish to finish ?","cancelLabel":"Cancel","confirmLabel":"Finish"},"confirmRetry":{"header":"Retry ?","body":"Are you sure you wish to retry ?","cancelLabel":"Cancel","confirmLabel":"Confirm"},"question":"
Which Earth layer is the densest? <\/p>\n"},"library":"H5P.MultiChoice 1.16","metadata":{"contentType":"Multiple Choice","license":"U","title":"Untitled Multiple Choice"},"subContentId":"924e8db3-4fbb-4785-aaa4-c500cf9e5164"},{"params":{"media":{"disableImageZooming":false},"answers":[{"correct":false,"tipsAndFeedback":{"tip":"","chosenFeedback":"","notChosenFeedback":""},"text":"
Crust<\/div>\n"},{"correct":false,"tipsAndFeedback":{"tip":"","chosenFeedback":"","notChosenFeedback":""},"text":"
Inner core<\/div>\n"},{"correct":true,"tipsAndFeedback":{"tip":"","chosenFeedback":"","notChosenFeedback":""},"text":"
Mantle<\/div>\n"},{"correct":false,"tipsAndFeedback":{"tip":"","chosenFeedback":"","notChosenFeedback":""},"text":"
Outer core<\/div>\n"}],"overallFeedback":[{"from":0,"to":100}],"behaviour":{"enableRetry":true,"enableSolutionsButton":false,"enableCheckButton":true,"type":"auto","singlePoint":false,"randomAnswers":false,"showSolutionsRequiresInput":true,"confirmCheckDialog":false,"confirmRetryDialog":false,"autoCheck":false,"passPercentage":100,"showScorePoints":true},"UI":{"checkAnswerButton":"Check","submitAnswerButton":"Submit","showSolutionButton":"Show solution","tryAgainButton":"Retry","tipsLabel":"Show tip","scoreBarLabel":"You got :num out of :total points","tipAvailable":"Tip available","feedbackAvailable":"Feedback available","readFeedback":"Read feedback","wrongAnswer":"Wrong answer","correctAnswer":"Correct answer","shouldCheck":"Should have been checked","shouldNotCheck":"Should not have been checked","noInput":"Please answer before viewing the solution","a11yCheck":"Check the answers. The responses will be marked as correct, incorrect, or unanswered.","a11yShowSolution":"Show the solution. The task will be marked with its correct solution.","a11yRetry":"Retry the task. Reset all responses and start the task over again."},"confirmCheck":{"header":"Finish ?","body":"Are you sure you wish to finish ?","cancelLabel":"Cancel","confirmLabel":"Finish"},"confirmRetry":{"header":"Retry ?","body":"Are you sure you wish to retry ?","cancelLabel":"Cancel","confirmLabel":"Confirm"},"question":"
Which Earth layer is the thickest (makes up the majority of the planet)?<\/p>\n"},"library":"H5P.MultiChoice 1.16","metadata":{"contentType":"Multiple Choice","license":"U","title":"Untitled Multiple Choice"},"subContentId":"277a1aad-61d0-4ed2-b156-c44cc82bd674"}],"disableBackwardsNavigation":false,"randomQuestions":false,"endGame":{"showResultPage":true,"showSolutionButton":false,"showRetryButton":true,"noResultMessage":"Finished","message":"Your result:","scoreBarLabel":"You got @finals out of @totals points","overallFeedback":[{"from":0,"to":100}],"solutionButtonText":"Show solution","retryButtonText":"Retry","finishButtonText":"Finish","submitButtonText":"Submit","showAnimations":false,"skippable":false,"skipButtonText":"Skip video"},"texts":{"prevButton":"Previous question","nextButton":"Next question","finishButton":"Finish","submitButton":"Submit","textualProgress":"Question: @current of @total questions","jumpToQuestion":"Question %d of %total","questionLabel":"Question","readSpeakerProgress":"Question @current of @total","unansweredText":"Unanswered","answeredText":"Answered","currentQuestionText":"Current question","navigationLabel":"Questions"},"override":{"checkButton":true,"showSolutionButton":"off","retryButton":"on"}},"library":"H5P.QuestionSet 1.20","metadata":{"contentType":"Question Set","license":"U","title":"Test Your Understanding"},"subContentId":"74c2aff6-7d67-4667-b631-0d09c6109efa"},"useSeparator":"auto"}]},"library":"H5P.Column 1.18","subContentId":"377725be-3977-4f76-86a8-a6de0870ca95","metadata":{"contentType":"Column","license":"U","title":"Earth's Layers"}},{"params":{"content":[{"content":{"params":{"decorative":false,"contentName":"Image","file":{"path":"images\/file-62b73e4bf142d.jpg","mime":"image\/jpeg","copyright":{"license":"U"},"width":1200,"height":656},"alt":"solar winds interacting with Earth's magnetic field","expandImage":"Expand Image","minimizeImage":"Minimize Image"},"library":"H5P.Image 1.1","metadata":{"contentType":"Image","license":"U","title":"Untitled Image"},"subContentId":"f0ae92d5-b603-4ff1-8703-12e1bedc1bfa"},"useSeparator":"auto"},{"content":{"params":{"text":"
Above figure: Solar winds blowing towards Earth and deflected by Earth's Magnetic Field. (NASA)<\/span><\/span><\/em><\/p>\n"},"library":"H5P.AdvancedText 1.1","metadata":{"contentType":"Text","license":"U","title":"Untitled Text"},"subContentId":"eca5aee1-676e-4e01-b6e2-ba32d3375ade"},"useSeparator":"auto"}]},"library":"H5P.Column 1.18","metadata":{"contentType":"Column","license":"U","title":"Solar Winds"},"subContentId":"ee4040d9-0710-430e-a760-dca76b4366e9"},{"params":{"content":[{"content":{"params":{"decorative":false,"contentName":"Image","alt":"Comparison of Earth's atmosphere to that of other planets","expandImage":"Expand Image","minimizeImage":"Minimize Image","title":"Comparison of Earth's atmosphere to that of other planets","file":{"path":"images\/file-67bbcc3c28d3e.jpg","mime":"image\/jpeg","copyright":{"license":"U"},"width":1400,"height":1072}},"library":"H5P.Image 1.1","metadata":{"contentType":"Image","license":"U","title":"Untitled Image"},"subContentId":"41b05359-4b8d-4261-8539-f30adef37fba"},"useSeparator":"auto"},{"content":{"params":{"text":"
Above image: Major gas components of the atmospheres of Earth and its neighboring planets, showing CO\u2082 as the dominant gas on Mars and Venus, while only a minor component on Earth.<\/em><\/p>
"},"library":"H5P.AdvancedText 1.1","metadata":{"contentType":"Text","license":"U","title":"Untitled Text"},"subContentId":"500e815f-96fa-48cf-99e9-887d5a046699"},"useSeparator":"auto"},{"content":{"params":{"text":"
Composition of Earth\u2019s early atmosphere:<\/strong><\/td> Composition of Earth\u2019s current atmosphere:<\/strong><\/td><\/tr>
In decreasing abundance<\/strong>
CO\u2082 (carbon dioxide)
N\u2082 (nitrogen)
H\u2082O (water vapor)
CH\u2084 (methane)
NH\u2083 (ammonia)
CO (carbon monoxide)
SO\u2082 (sulfur dioxide)
H\u2082S (hydrogen sulfide)
HCN (hydrogen cyanide)<\/td> MAJOR<\/strong>
78% N\u2082 (nitrogen)
21% O\u2082 (oxygen)
MINOR<\/strong>
0-4% H\u2082O (water)
0.9% Ar (Argon)
0.04% CO\u2082 (carbon dioxide)<\/td><\/tr><\/tbody><\/table>
<\/div>"},"library":"H5P.Table 1.2","metadata":{"contentType":"Table","license":"U","title":"Atmosphere Comparison"},"subContentId":"adeec432-5b27-4d51-a121-b4b8a0394b5a"},"useSeparator":"auto"},{"content":{"params":{"text":"
From the video: <\/p>
\"With a magnetic field deflecting solar winds, Earth\u2019s atmosphere started to collect. What was the source of the gases that collected? The molten Earth \u2013 with gases bubbling up from the molten rock. Once the earth\u2019s surface cooled enough to create a solid surface, these gases continued to erupt from volcanoes. Volcanoes are a major source of gases like water, carbon dioxide, and sulfur dioxide. Gases also entered the newly growing atmosphere from comets colliding with Earth. As we reviewed in the Earth Formation video tutorial, comets contain water, ammonia, and carbon dioxide.<\/p>
Early earth\u2019s atmosphere was hot and toxic. Its primary ingredient was carbon dioxide, but it also contained small amounts of sulfurous compounds, carbon monoxide, methane, and cyanide. Let\u2019s compare early earth\u2019s atmosphere with the atmospheres of other rocky planets in our solar system today. The three rocky planets with atmospheres (Mercury has no atmosphere) show two very similar atmosphere and one very different one \u2013 Earth\u2019s. Venus and Mars both have carbon dioxide as the major atmospheric gas, much like Earth\u2019s early atmosphere, followed by nitrogen and argon. Notice the lack of any oxygen. Why is Earth\u2019s atmosphere today so different than it was originally and so different than the other two rocky planets that are its neighbors??

First, as the early Earth lost some of its initial heat of formation and cooled, not only did the surface crust harden, but it also allowed the water present in the early atmosphere to cool enough for it to rain down and cover the hard crust with oceans. These early rains would have removed most of the water from the atmosphere, leaving it, like today, as only 1-4% by mass, depending on the climate. What happens next? Water is a giant absorber for carbon dioxide (we say that carbon dioxide is highly soluble in water), so once the oceans formed, much of the carbon dioxide in the atmosphere would have dissolved into it. We take advantage of the high solubility of carbon dioxide today when we use it to carbonate beverages.<\/p>"},"library":"H5P.AdvancedText 1.1","metadata":{"contentType":"Text","license":"U","title":"Untitled Text"},"subContentId":"0ffc4fd6-ac76-4c50-982a-ff351b385c66"},"useSeparator":"auto"},{"content":{"params":{"introPage":{"showIntroPage":false,"startButtonText":"Start Quiz","introduction":""},"progressType":"dots","passPercentage":100,"questions":[{"params":{"media":{"disableImageZooming":false},"answers":[{"correct":false,"tipsAndFeedback":{"tip":"","chosenFeedback":"","notChosenFeedback":""},"text":"
Ammonia<\/div>\n"},{"correct":true,"tipsAndFeedback":{"tip":"","chosenFeedback":"","notChosenFeedback":""},"text":"
Carbon Dioxide<\/div>\n"},{"correct":false,"tipsAndFeedback":{"tip":"","chosenFeedback":"","notChosenFeedback":""},"text":"
Methane<\/div>\n"},{"correct":false,"tipsAndFeedback":{"tip":"","chosenFeedback":"","notChosenFeedback":""},"text":"
Nitrogen<\/div>\n"},{"correct":false,"tipsAndFeedback":{"tip":"","chosenFeedback":"","notChosenFeedback":""},"text":"
Oxygen<\/div>\n"},{"correct":false,"tipsAndFeedback":{"tip":"","chosenFeedback":"","notChosenFeedback":""},"text":"
Water<\/div>\n"}],"overallFeedback":[{"from":0,"to":100}],"behaviour":{"enableRetry":true,"enableSolutionsButton":false,"enableCheckButton":true,"type":"auto","singlePoint":false,"randomAnswers":false,"showSolutionsRequiresInput":true,"confirmCheckDialog":false,"confirmRetryDialog":false,"autoCheck":false,"passPercentage":100,"showScorePoints":true},"UI":{"checkAnswerButton":"Check","submitAnswerButton":"Submit","showSolutionButton":"Show solution","tryAgainButton":"Retry","tipsLabel":"Show tip","scoreBarLabel":"You got :num out of :total points","tipAvailable":"Tip available","feedbackAvailable":"Feedback available","readFeedback":"Read feedback","wrongAnswer":"Wrong answer","correctAnswer":"Correct answer","shouldCheck":"Should have been checked","shouldNotCheck":"Should not have been checked","noInput":"Please answer before viewing the solution","a11yCheck":"Check the answers. The responses will be marked as correct, incorrect, or unanswered.","a11yShowSolution":"Show the solution. The task will be marked with its correct solution.","a11yRetry":"Retry the task. Reset all responses and start the task over again."},"confirmCheck":{"header":"Finish ?","body":"Are you sure you wish to finish ?","cancelLabel":"Cancel","confirmLabel":"Finish"},"confirmRetry":{"header":"Retry ?","body":"Are you sure you wish to retry ?","cancelLabel":"Cancel","confirmLabel":"Confirm"},"question":"
What is the dominant<\/strong> atmospheric gas on Venus <\/strong>and Mars<\/strong>? <\/p>\n"},"library":"H5P.MultiChoice 1.16","metadata":{"contentType":"Multiple Choice","license":"U","title":"Untitled Multiple Choice"},"subContentId":"6f117361-1439-421f-8c63-694f0466905a"},{"params":{"media":{"disableImageZooming":false},"answers":[{"correct":false,"tipsAndFeedback":{"tip":"","chosenFeedback":"","notChosenFeedback":""},"text":"
Ammonia<\/div>\n"},{"correct":true,"tipsAndFeedback":{"tip":"","chosenFeedback":"","notChosenFeedback":""},"text":"
Carbon Dioxide<\/div>\n"},{"correct":false,"tipsAndFeedback":{"tip":"","chosenFeedback":"","notChosenFeedback":""},"text":"
Methane<\/div>\n"},{"correct":false,"tipsAndFeedback":{"tip":"","chosenFeedback":"","notChosenFeedback":""},"text":"
Nitrogen<\/div>\n"},{"correct":false,"tipsAndFeedback":{"tip":"","chosenFeedback":"","notChosenFeedback":""},"text":"
Oxygen<\/div>\n"},{"correct":false,"tipsAndFeedback":{"tip":"","chosenFeedback":"","notChosenFeedback":""},"text":"
Water<\/div>\n"}],"overallFeedback":[{"from":0,"to":100}],"behaviour":{"enableRetry":true,"enableSolutionsButton":false,"enableCheckButton":true,"type":"auto","singlePoint":false,"randomAnswers":false,"showSolutionsRequiresInput":true,"confirmCheckDialog":false,"confirmRetryDialog":false,"autoCheck":false,"passPercentage":100,"showScorePoints":true},"UI":{"checkAnswerButton":"Check","submitAnswerButton":"Submit","showSolutionButton":"Show solution","tryAgainButton":"Retry","tipsLabel":"Show tip","scoreBarLabel":"You got :num out of :total points","tipAvailable":"Tip available","feedbackAvailable":"Feedback available","readFeedback":"Read feedback","wrongAnswer":"Wrong answer","correctAnswer":"Correct answer","shouldCheck":"Should have been checked","shouldNotCheck":"Should not have been checked","noInput":"Please answer before viewing the solution","a11yCheck":"Check the answers. The responses will be marked as correct, incorrect, or unanswered.","a11yShowSolution":"Show the solution. The task will be marked with its correct solution.","a11yRetry":"Retry the task. Reset all responses and start the task over again."},"confirmCheck":{"header":"Finish ?","body":"Are you sure you wish to finish ?","cancelLabel":"Cancel","confirmLabel":"Finish"},"confirmRetry":{"header":"Retry ?","body":"Are you sure you wish to retry ?","cancelLabel":"Cancel","confirmLabel":"Confirm"},"question":"
What was <\/strong>the dominant<\/strong> atmospheric gas on Earth when Earth first formed? <\/p>\n"},"library":"H5P.MultiChoice 1.16","metadata":{"contentType":"Multiple Choice","license":"U","title":"Untitled Multiple Choice"},"subContentId":"5736972d-b37a-4ce9-a94d-084aacdc98e6"},{"params":{"media":{"disableImageZooming":false},"answers":[{"correct":false,"tipsAndFeedback":{"tip":"","chosenFeedback":"","notChosenFeedback":""},"text":"
Argon<\/div>\n"},{"correct":false,"tipsAndFeedback":{"tip":"","chosenFeedback":"","notChosenFeedback":""},"text":"
Carbon Dioxide<\/div>\n"},{"correct":false,"tipsAndFeedback":{"tip":"","chosenFeedback":"","notChosenFeedback":""},"text":"
Methane<\/div>\n"},{"correct":true,"tipsAndFeedback":{"tip":"","chosenFeedback":"","notChosenFeedback":""},"text":"
Nitrogen<\/div>\n"},{"correct":false,"tipsAndFeedback":{"tip":"","chosenFeedback":"","notChosenFeedback":""},"text":"
Oxygen<\/div>\n"},{"correct":false,"tipsAndFeedback":{"tip":"","chosenFeedback":"","notChosenFeedback":""},"text":"
Water<\/div>\n"}],"overallFeedback":[{"from":0,"to":100}],"behaviour":{"enableRetry":true,"enableSolutionsButton":false,"enableCheckButton":true,"type":"auto","singlePoint":false,"randomAnswers":false,"showSolutionsRequiresInput":true,"confirmCheckDialog":false,"confirmRetryDialog":false,"autoCheck":false,"passPercentage":100,"showScorePoints":true},"UI":{"checkAnswerButton":"Check","submitAnswerButton":"Submit","showSolutionButton":"Show solution","tryAgainButton":"Retry","tipsLabel":"Show tip","scoreBarLabel":"You got :num out of :total points","tipAvailable":"Tip available","feedbackAvailable":"Feedback available","readFeedback":"Read feedback","wrongAnswer":"Wrong answer","correctAnswer":"Correct answer","shouldCheck":"Should have been checked","shouldNotCheck":"Should not have been checked","noInput":"Please answer before viewing the solution","a11yCheck":"Check the answers. The responses will be marked as correct, incorrect, or unanswered.","a11yShowSolution":"Show the solution. The task will be marked with its correct solution.","a11yRetry":"Retry the task. Reset all responses and start the task over again."},"confirmCheck":{"header":"Finish ?","body":"Are you sure you wish to finish ?","cancelLabel":"Cancel","confirmLabel":"Finish"},"confirmRetry":{"header":"Retry ?","body":"Are you sure you wish to retry ?","cancelLabel":"Cancel","confirmLabel":"Confirm"},"question":"
What is the dominant<\/strong> atmospheric gas on Earth today? <\/p>\n"},"library":"H5P.MultiChoice 1.16","metadata":{"contentType":"Multiple Choice","license":"U","title":"Untitled Multiple Choice"},"subContentId":"08da8df6-8326-44ae-88c2-9b1fe2ad3d92"},{"params":{"media":{"disableImageZooming":false},"answers":[{"correct":false,"tipsAndFeedback":{"tip":"","chosenFeedback":"","notChosenFeedback":""},"text":"
Argon<\/div>\n"},{"correct":true,"tipsAndFeedback":{"tip":"","chosenFeedback":"","notChosenFeedback":""},"text":"
Carbon Dioxide<\/div>\n"},{"correct":false,"tipsAndFeedback":{"tip":"","chosenFeedback":"","notChosenFeedback":""},"text":"
Nitrogen<\/div>\n"},{"correct":false,"tipsAndFeedback":{"tip":"","chosenFeedback":"","notChosenFeedback":""},"text":"
Oxygen<\/div>\n"},{"correct":false,"tipsAndFeedback":{"tip":"","chosenFeedback":"","notChosenFeedback":""},"text":"
Water<\/div>\n"}],"overallFeedback":[{"from":0,"to":100}],"behaviour":{"enableRetry":true,"enableSolutionsButton":false,"enableCheckButton":true,"type":"auto","singlePoint":false,"randomAnswers":false,"showSolutionsRequiresInput":true,"confirmCheckDialog":false,"confirmRetryDialog":false,"autoCheck":false,"passPercentage":100,"showScorePoints":true},"UI":{"checkAnswerButton":"Check","submitAnswerButton":"Submit","showSolutionButton":"Show solution","tryAgainButton":"Retry","tipsLabel":"Show tip","scoreBarLabel":"You got :num out of :total points","tipAvailable":"Tip available","feedbackAvailable":"Feedback available","readFeedback":"Read feedback","wrongAnswer":"Wrong answer","correctAnswer":"Correct answer","shouldCheck":"Should have been checked","shouldNotCheck":"Should not have been checked","noInput":"Please answer before viewing the solution","a11yCheck":"Check the answers. The responses will be marked as correct, incorrect, or unanswered.","a11yShowSolution":"Show the solution. The task will be marked with its correct solution.","a11yRetry":"Retry the task. Reset all responses and start the task over again."},"confirmCheck":{"header":"Finish ?","body":"Are you sure you wish to finish ?","cancelLabel":"Cancel","confirmLabel":"Finish"},"confirmRetry":{"header":"Retry ?","body":"Are you sure you wish to retry ?","cancelLabel":"Cancel","confirmLabel":"Confirm"},"question":"
Which gas in this list is the one present in the least amount in Earth's current <\/strong>atmosphere<\/p>\n"},"library":"H5P.MultiChoice 1.16","metadata":{"contentType":"Multiple Choice","license":"U","title":"Untitled Multiple Choice"},"subContentId":"b008d201-659f-4b7f-8bb3-4a8efa3982b5"},{"params":{"media":{"disableImageZooming":false},"answers":[{"correct":false,"tipsAndFeedback":{"tip":"","chosenFeedback":"","notChosenFeedback":""},"text":"
Argon<\/div>\n"},{"correct":false,"tipsAndFeedback":{"tip":"","chosenFeedback":"","notChosenFeedback":""},"text":"
Carbon Dioxide<\/div>\n"},{"correct":false,"tipsAndFeedback":{"tip":"","chosenFeedback":"","notChosenFeedback":""},"text":"
Nitrogen<\/div>\n"},{"correct":true,"tipsAndFeedback":{"tip":"","chosenFeedback":"","notChosenFeedback":""},"text":"
Oxygen<\/div>\n"},{"correct":false,"tipsAndFeedback":{"tip":"","chosenFeedback":"","notChosenFeedback":""},"text":"
Water<\/div>\n"}],"overallFeedback":[{"from":0,"to":100}],"behaviour":{"enableRetry":true,"enableSolutionsButton":false,"enableCheckButton":true,"type":"auto","singlePoint":false,"randomAnswers":false,"showSolutionsRequiresInput":true,"confirmCheckDialog":false,"confirmRetryDialog":false,"autoCheck":false,"passPercentage":100,"showScorePoints":true},"UI":{"checkAnswerButton":"Check","submitAnswerButton":"Submit","showSolutionButton":"Show solution","tryAgainButton":"Retry","tipsLabel":"Show tip","scoreBarLabel":"You got :num out of :total points","tipAvailable":"Tip available","feedbackAvailable":"Feedback available","readFeedback":"Read feedback","wrongAnswer":"Wrong answer","correctAnswer":"Correct answer","shouldCheck":"Should have been checked","shouldNotCheck":"Should not have been checked","noInput":"Please answer before viewing the solution","a11yCheck":"Check the answers. The responses will be marked as correct, incorrect, or unanswered.","a11yShowSolution":"Show the solution. The task will be marked with its correct solution.","a11yRetry":"Retry the task. Reset all responses and start the task over again."},"confirmCheck":{"header":"Finish ?","body":"Are you sure you wish to finish ?","cancelLabel":"Cancel","confirmLabel":"Finish"},"confirmRetry":{"header":"Retry ?","body":"Are you sure you wish to retry ?","cancelLabel":"Cancel","confirmLabel":"Confirm"},"question":"
Which gas in this list is present in high amounts in Earth's current <\/strong>atmosphere but was completely absent in early Earth<\/strong>?<\/p>\n"},"library":"H5P.MultiChoice 1.16","metadata":{"contentType":"Multiple Choice","license":"U","title":"Untitled Multiple Choice"},"subContentId":"1079f02c-ffdd-43c9-8a38-53a174b7337e"},{"params":{"media":{"disableImageZooming":false},"answers":[{"correct":true,"tipsAndFeedback":{"chosenFeedback":"
Corect! Photosynthesis is a process completed by living organisms and it removes carbon dioxide and produces oxygen.<\/div>\n","tip":"","notChosenFeedback":""},"text":"
Life<\/div>\n"},{"correct":false,"tipsAndFeedback":{"chosenFeedback":"
Magnetic field has nothing to do with the types of gasses collected, only the volume.<\/div>\n","tip":"","notChosenFeedback":""},"text":"
Magnetic field<\/div>\n"},{"correct":true,"tipsAndFeedback":{"chosenFeedback":"
Correct! Oceans absorb carbon dioxide gas (which has a high gas solubility!).<\/div>\n","tip":"","notChosenFeedback":""},"text":"
Oceans<\/div>\n"},{"correct":false,"tipsAndFeedback":{"chosenFeedback":"
Volcanic eruptions happen on most planets<\/div>\n","tip":"","notChosenFeedback":""},"text":"
Volcanic eruptions<\/div>\n"}],"overallFeedback":[{"from":0,"to":100}],"behaviour":{"enableRetry":true,"enableSolutionsButton":false,"enableCheckButton":true,"type":"auto","singlePoint":false,"randomAnswers":false,"showSolutionsRequiresInput":true,"confirmCheckDialog":false,"confirmRetryDialog":false,"autoCheck":false,"passPercentage":100,"showScorePoints":true},"UI":{"checkAnswerButton":"Check","submitAnswerButton":"Submit","showSolutionButton":"Show solution","tryAgainButton":"Retry","tipsLabel":"Show tip","scoreBarLabel":"You got :num out of :total points","tipAvailable":"Tip available","feedbackAvailable":"Feedback available","readFeedback":"Read feedback","wrongAnswer":"Wrong answer","correctAnswer":"Correct answer","shouldCheck":"Should have been checked","shouldNotCheck":"Should not have been checked","noInput":"Please answer before viewing the solution","a11yCheck":"Check the answers. The responses will be marked as correct, incorrect, or unanswered.","a11yShowSolution":"Show the solution. The task will be marked with its correct solution.","a11yRetry":"Retry the task. Reset all responses and start the task over again."},"confirmCheck":{"header":"Finish ?","body":"Are you sure you wish to finish ?","cancelLabel":"Cancel","confirmLabel":"Finish"},"confirmRetry":{"header":"Retry ?","body":"Are you sure you wish to retry ?","cancelLabel":"Cancel","confirmLabel":"Confirm"},"question":"
Which of the following elements of Earth are NOT <\/strong>present on other planets AND can explain the significant differences in atmospheres among the planets today? (Choose all that apply.)<\/em><\/p>\n"},"library":"H5P.MultiChoice 1.16","metadata":{"contentType":"Multiple Choice","license":"U","title":"Explain differences"},"subContentId":"2c3f82bf-7477-4cfb-83dd-f16c2ccd9001"}],"disableBackwardsNavigation":false,"randomQuestions":false,"endGame":{"showResultPage":true,"showSolutionButton":false,"showRetryButton":true,"noResultMessage":"Finished","message":"Your result:","scoreBarLabel":"You got @finals out of @totals points","overallFeedback":[{"from":0,"to":100}],"solutionButtonText":"Show solution","retryButtonText":"Retry","finishButtonText":"Finish","submitButtonText":"Submit","showAnimations":false,"skippable":false,"skipButtonText":"Skip video"},"texts":{"prevButton":"Previous question","nextButton":"Next question","finishButton":"Finish","submitButton":"Submit","textualProgress":"Question: @current of @total questions","jumpToQuestion":"Question %d of %total","questionLabel":"Question","readSpeakerProgress":"Question @current of @total","unansweredText":"Unanswered","answeredText":"Answered","currentQuestionText":"Current question","navigationLabel":"Questions"},"override":{"checkButton":true,"showSolutionButton":"off","retryButton":"on"}},"library":"H5P.QuestionSet 1.20","metadata":{"contentType":"Question Set","license":"U","title":"Test Your Understanding"},"subContentId":"ab34ef89-6780-435b-a1b6-4bdbc1ecda51"},"useSeparator":"auto"}]},"library":"H5P.Column 1.18","metadata":{"contentType":"Column","license":"U","title":"Atmosphere Evolution"},"subContentId":"4f1d6c24-92f5-4758-9d7d-b92ced88dfb1"},{"params":{"content":[{"content":{"params":{"introPage":{"showIntroPage":false,"startButtonText":"Start Quiz","introduction":""},"progressType":"dots","passPercentage":100,"questions":[{"params":{"media":{"disableImageZooming":false},"answers":[{"correct":false,"tipsAndFeedback":{"tip":"","chosenFeedback":"","notChosenFeedback":""},"text":"
13.8 Ga<\/div>\n"},{"correct":true,"tipsAndFeedback":{"tip":"","chosenFeedback":"","notChosenFeedback":""},"text":"
4.6 Ga<\/div>\n"},{"correct":false,"tipsAndFeedback":{"tip":"","chosenFeedback":"","notChosenFeedback":""},"text":"
4.4 Ga<\/div>\n"},{"correct":false,"tipsAndFeedback":{"tip":"","chosenFeedback":"","notChosenFeedback":""},"text":"
4.0 Ga<\/div>\n"},{"correct":false,"tipsAndFeedback":{"tip":"","chosenFeedback":"","notChosenFeedback":""},"text":"
3.85 Ga<\/div>\n"},{"correct":false,"tipsAndFeedback":{"tip":"","chosenFeedback":"","notChosenFeedback":""},"text":"
3.5 Ga<\/div>\n"},{"correct":false,"tipsAndFeedback":{"tip":"","chosenFeedback":"","notChosenFeedback":""},"text":"
13.6 Ma<\/div>\n"},{"correct":false,"tipsAndFeedback":{"tip":"","chosenFeedback":"","notChosenFeedback":""},"text":"
4.6 Ma<\/div>\n"},{"correct":false,"tipsAndFeedback":{"tip":"","chosenFeedback":"","notChosenFeedback":""},"text":"
4.4 Ma<\/div>\n"},{"correct":false,"tipsAndFeedback":{"tip":"","chosenFeedback":"","notChosenFeedback":""},"text":"
4.0 Ma<\/div>\n"},{"correct":false,"tipsAndFeedback":{"tip":"","chosenFeedback":"","notChosenFeedback":""},"text":"
3.85 Ma<\/div>\n"},{"correct":false,"tipsAndFeedback":{"tip":"","chosenFeedback":"","notChosenFeedback":""},"text":"
3.5 Ma<\/div>\n"}],"overallFeedback":[{"from":0,"to":100}],"behaviour":{"enableRetry":true,"enableSolutionsButton":false,"enableCheckButton":true,"type":"auto","singlePoint":false,"randomAnswers":false,"showSolutionsRequiresInput":true,"confirmCheckDialog":false,"confirmRetryDialog":false,"autoCheck":false,"passPercentage":100,"showScorePoints":true},"UI":{"checkAnswerButton":"Check","submitAnswerButton":"Submit","showSolutionButton":"Show solution","tryAgainButton":"Retry","tipsLabel":"Show tip","scoreBarLabel":"You got :num out of :total points","tipAvailable":"Tip available","feedbackAvailable":"Feedback available","readFeedback":"Read feedback","wrongAnswer":"Wrong answer","correctAnswer":"Correct answer","shouldCheck":"Should have been checked","shouldNotCheck":"Should not have been checked","noInput":"Please answer before viewing the solution","a11yCheck":"Check the answers. The responses will be marked as correct, incorrect, or unanswered.","a11yShowSolution":"Show the solution. The task will be marked with its correct solution.","a11yRetry":"Retry the task. Reset all responses and start the task over again."},"confirmCheck":{"header":"Finish ?","body":"Are you sure you wish to finish ?","cancelLabel":"Cancel","confirmLabel":"Finish"},"confirmRetry":{"header":"Retry ?","body":"Are you sure you wish to retry ?","cancelLabel":"Cancel","confirmLabel":"Confirm"},"question":"
When did planet Earth form? (Remember: Ga = Billions of years ago and Ma = Millions of years ago)<\/em><\/p>\n"},"library":"H5P.MultiChoice 1.16","metadata":{"contentType":"Multiple Choice","license":"U","title":"Earth formation"},"subContentId":"020245aa-c518-412a-9d38-b4e0027bc576"},{"params":{"media":{"disableImageZooming":false},"taskDescription":"Drag the words into the correct boxes","overallFeedback":[{"from":0,"to":100}],"checkAnswer":"Check","submitAnswer":"Submit","tryAgain":"Retry","showSolution":"Show solution","dropZoneIndex":"Drop Zone @index.","empty":"Drop Zone @index is empty.","contains":"Drop Zone @index contains draggable @draggable.","ariaDraggableIndex":"@index of @count draggables.","tipLabel":"Show tip","correctText":"Correct!","incorrectText":"Incorrect!","resetDropTitle":"Reset drop","resetDropDescription":"Are you sure you want to reset this drop zone?","grabbed":"Draggable is grabbed.","cancelledDragging":"Cancelled dragging.","correctAnswer":"Correct answer:","feedbackHeader":"Feedback","behaviour":{"enableRetry":true,"enableSolutionsButton":true,"enableCheckButton":true,"instantFeedback":false},"scoreBarLabel":"You got :num out of :total points","a11yCheck":"Check the answers. The responses will be marked as correct, incorrect, or unanswered.","a11yShowSolution":"Show the solution. The task will be marked with its correct solution.","a11yRetry":"Retry the task. Reset all responses and start the task over again.","textField":"Order these events from the first 600 million years of Earth's history into their order of occurrence (starting at the bottom and working upwards):\n\nMost recent event in this list: *Life evolves*\n\nNext to occur: *Oceans form*\n\nNext to occur: *Hard crust forms*\n\nFirst to occur (oldest event in this list): *Earth formed*"},"library":"H5P.DragText 1.10","metadata":{"contentType":"Drag the Words","license":"U","title":"Untitled Drag the Words"},"subContentId":"45b5d7fe-3ed8-48e4-ac1f-c35b15d7aae1"}],"disableBackwardsNavigation":false,"randomQuestions":false,"endGame":{"showResultPage":true,"showSolutionButton":false,"showRetryButton":true,"noResultMessage":"Finished","message":"Your result:","scoreBarLabel":"You got @finals out of @totals points","overallFeedback":[{"from":0,"to":100}],"solutionButtonText":"Show solution","retryButtonText":"Retry","finishButtonText":"Finish","submitButtonText":"Submit","showAnimations":false,"skippable":false,"skipButtonText":"Skip video"},"texts":{"prevButton":"Previous question","nextButton":"Next question","finishButton":"Finish","submitButton":"Submit","textualProgress":"Question: @current of @total questions","jumpToQuestion":"Question %d of %total","questionLabel":"Question","readSpeakerProgress":"Question @current of @total","unansweredText":"Unanswered","answeredText":"Answered","currentQuestionText":"Current question","navigationLabel":"Questions"},"override":{"checkButton":true,"showSolutionButton":"off","retryButton":"on"}},"library":"H5P.QuestionSet 1.20","metadata":{"contentType":"Question Set","license":"U","title":"Test Your Understanding"},"subContentId":"0c0401f7-3a68-49a1-8bcf-ba0242222e66"},"useSeparator":"auto"}]},"library":"H5P.Column 1.18","subContentId":"6798a59c-f03d-4839-a66b-3f0e6ec10807","metadata":{"contentType":"Column","license":"U","title":"Test Your Understanding"}},{"params":{"content":[{"content":{"params":{"text":"
\n
The following resources are optional and intended for deeper exploration or clarification.<\/p>\n\n
\n
Textbook chapters<\/strong><\/p>\n\n
\n\t
Open Textbook: Physical Geology, by Steven Earle -- The Origins of Earth and the Solar System<\/a><\/li>\n\t
Open Textbook: Introduction to Geology, SLCC -- Origin of Universe and Solar System<\/a> <\/li>\n<\/ul>\n\n
\n
Additional resources<\/strong><\/p>\n\n
\n\tLecture photo album: Earth History (Fossils and Other Evidence)<\/a><\/li>\n\t
Lecture photo album: Auroras <\/a>(examples of how the Solar Winds enter Earth's atmosphere at the poles and strip electrons off gas molecules; when those electrons return back, they give off light).<\/li>\n\t
Website interactive: Deep Time<\/a> -- Howard Hughes Medical Institute<\/li>\n\t
How do we date rocks? Tutorial: Radiometric Dating<\/a><\/li>\n<\/ul>\n"},"library":"H5P.AdvancedText 1.1","metadata":{"contentType":"Text","license":"U","title":"Untitled Text"},"subContentId":"350f8aa5-5fe3-4376-9b36-07183dcc6570"},"useSeparator":"auto"}]},"library":"H5P.Column 1.18","subContentId":"5502f69d-e535-4335-86b9-1980cdb8917f","metadata":{"contentType":"Column","license":"U","title":"Additional Resources"}}],"behaviour":{"defaultTableOfContents":true,"progressIndicators":true,"progressAuto":true,"displaySummary":false,"baseColor":"#1768c4","enableRetry":true},"read":"Read","displayTOC":"Display 'Table of contents'","hideTOC":"Hide 'Table of contents'","nextPage":"Next page","previousPage":"Previous page","chapterCompleted":"Page completed!","partCompleted":"@pages of @total completed","incompleteChapter":"Incomplete page","navigateToTop":"Navigate to the top","markAsFinished":"I have finished this page","fullscreen":"Fullscreen","exitFullscreen":"Exit fullscreen","bookProgressSubtext":"@count of @total pages","interactionsProgressSubtext":"@count of @total interactions","submitReport":"Submit Report","restartLabel":"Restart","summaryHeader":"Summary","allInteractions":"All interactions","unansweredInteractions":"Unanswered interactions","scoreText":"@score \/ @maxscore","leftOutOfTotalCompleted":"@left of @max interactions completed","noInteractions":"No interactions","score":"Score","summaryAndSubmit":"Summary & submit","noChapterInteractionBoldText":"You have not interacted with any pages.","noChapterInteractionText":"You have to interact with at least one page before you can see the summary.","yourAnswersAreSubmittedForReview":"Your answers are submitted for review!","bookProgress":"Book progress","interactionsProgress":"Interactions progress","totalScoreLabel":"Total score","a11y":{"progress":"Page @page of @total.","menu":"Toggle navigation menu"}}

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