https://www.khanacademy.org/science/strengthened-shs-earth-and-space-science-1/x006d5d274c051fd7:origin-and-structure-of-the-earth/x006d5d274c051fd7:earth-s-place-in-the-solar-system/v/bhp-what-was-young-earth-like 2023-07-02T10:05:56.724382666Z WATCH: What Was The Young Earth Like? Our planet has changed over time. Learn about the fiery, inhospitable conditions of the early Earth, four-and-a-half billion years ago. Understand why it was so hot, and how this heat led to the formation of Earth's layered structure. Explore theory of plate tectonics and its role in shaping our planet's continents, mountains, and oceans. Big History Project video https://cdn.kastatic.org/googleusercontent/JYMByeuyM4PywPhHQKK9y3-tkdClawKe4ttn8Iw_5723ny8Eyzx8DMHk66tjS-hEY41WZk_i6bRGgAue1vEi7AbL WATCH: What Was The Young Earth Like? Our planet has changed over time. Learn about the fiery, inhospitable conditions of the early Earth, four-and-a-half billion years ago. Understand why it was so hot, and how this heat led to the formation of Earth's layered structure. Explore theory of plate tectonics and its role in shaping our planet's continents, mountains, and oceans. https://cdn.kastatic.org/ka-youtube-converted/6bpoes4E8Vs.mp4/6bpoes4E8Vs.mp4 670 Earth's place in the solar system https://www.khanacademy.org/science/strengthened-shs-earth-and-space-science-1/x006d5d274c051fd7:origin-and-structure-of-the-earth/x006d5d274c051fd7:earth-s-place-in-the-solar-system/v/bhp-earth-life-interact 2023-07-02T10:05:56.724382666Z WATCH: How Do Earth and Life Interact? What does it mean when we say that we live in a "comfort zone" on earth, and how do life and the biosphere work to create conditions that humans and other living things can survive in? Explore the biosphere's history shaped by astronomical, geological, and biological forces. Discover how Earth's relationship with the sun, tectonic plate movements, and life itself have influenced the biosphere. Learn about mass extinction events, the role of asteroids, and the impact of human activity on our fragile biosphere. Big History Project video https://cdn.kastatic.org/googleusercontent/dTVLK-JS8j4zMg_43WKskZay4A69LBXJ7cr4UqNsQ2ow5qPsrnW1jfS59iUh41QuLpOMTvxpxGdkmh5Wx76oxPVfzQ WATCH: How Do Earth and Life Interact? What does it mean when we say that we live in a "comfort zone" on earth, and how do life and the biosphere work to create conditions that humans and other living things can survive in? Explore the biosphere's history shaped by astronomical, geological, and biological forces. Discover how Earth's relationship with the sun, tectonic plate movements, and life itself have influenced the biosphere. Learn about mass extinction events, the role of asteroids, and the impact of human activity on our fragile biosphere. https://cdn.kastatic.org/ka-youtube-converted/rxMF2RYzlto.mp4/rxMF2RYzlto.mp4 598 Earth's place in the solar system https://www.khanacademy.org/science/hs-bio/x230b3ff252126bb6:ecology-and-natural-systems/x230b3ff252126bb6:organization-of-natural-systems/a/organization-of-natural-systems 2025-04-14T14:10:21.945743561Z Earth's natural systems Learn about biotic and abiotic factors and how these form Earth's natural systems: the atmosphere, the biosphere, the geosphere, and the hydrosphere. article https://www.khanacademy.org/science/hs-bio/x230b3ff252126bb6:ecology-and-natural-systems/x230b3ff252126bb6:organization-of-natural-systems/v/biotic-and-abiotic-factors-in-earths-natural-systems 2024-05-28T21:41:02.467178644Z Biotic and abiotic factors in Earth’s natural systems Natural systems are made up of both biotic factors (living organisms and their interactions) and abiotic factors (non-living parts of the environment such as sunlight and temperature). Earth can be divided into four systems, called spheres: the atmosphere (gases surrounding Earth), the biosphere (all living organisms), the geosphere (Earth's interior and surface), and the hydrosphere (all forms of water). Sal Khan video https://cdn.kastatic.org/ka_thumbnails_cache/1b8f7160-2496-44ec-8a88-7e34c7fc5c26_1280_720_base.png Biotic and abiotic factors in Earth’s natural systems Natural systems are made up of both biotic factors (living organisms and their interactions) and abiotic factors (non-living parts of the environment such as sunlight and temperature). Earth can be divided into four systems, called spheres: the atmosphere (gases surrounding Earth), the biosphere (all living organisms), the geosphere (Earth's interior and surface), and the hydrosphere (all forms of water). https://cdn.kastatic.org/ka-youtube-converted/GxKWCiZHsvo.mp4/GxKWCiZHsvo.mp4 314 Earth's place in the solar system https://www.khanacademy.org/science/strengthened-shs-earth-and-space-science-1/x006d5d274c051fd7:origin-and-structure-of-the-earth/x006d5d274c051fd7:earth-s-place-in-the-solar-system/a/what-is-the-biosphere- 2023-05-05T21:01:11.640988085Z READ: What Is the Biosphere? article https://www.khanacademy.org/science/strengthened-shs-earth-and-space-science-1/x006d5d274c051fd7:origin-and-structure-of-the-earth/x006d5d274c051fd7:earth-s-place-in-the-solar-system/v/bhp-earth-and-early-atmosphere 2023-07-02T10:05:56.724382666Z WATCH: Earth and the Early Atmosphere The Earth's atmosphere keeps changing, creating an endless cycle of warming, cooling, and recovery. Discover how Earth's early atmosphere formed and evolved, as violent collisions that created intense heat and pressure, the formation of oceans, and the creation of the moon. Explore the rise of oxygen, the role of cyanobacteria, and the changes that led to today's diverse life forms. Big History Project video https://cdn.kastatic.org/googleusercontent/Sfjp8NfDD5pJAsTFtTPhmuuPF9JkRzobuADDtJ33zckSRw4j85FMXBJqiPJJzn41bP70vyYXxlBCQtBUpYPUiwA WATCH: Earth and the Early Atmosphere The Earth's atmosphere keeps changing, creating an endless cycle of warming, cooling, and recovery. Discover how Earth's early atmosphere formed and evolved, as violent collisions that created intense heat and pressure, the formation of oceans, and the creation of the moon. Explore the rise of oxygen, the role of cyanobacteria, and the changes that led to today's diverse life forms. https://cdn.kastatic.org/ka-youtube-converted/Gyn754vw8ZQ.mp4/Gyn754vw8ZQ.mp4 333 Earth's place in the solar system https://www.khanacademy.org/science/ap-college-environmental-science/x0b0e430a38ebd23f:earth-systems-and-resources/x0b0e430a38ebd23f:earths-air-and-water/a/earth-s-atmosphere 2022-09-16T02:37:58.737082894Z Earth's atmosphere Review your understanding of the composition and layers of Earth's atmosphere in this free article aligned to AP standards. article https://www.khanacademy.org/science/revision-up-science-class-6-full-term/x00110b31861f2508:week-4/x00110b31861f2508:nature-s-treasures/v/water 2025-01-27T07:04:21.433023569Z Water Water scarcity is a major problem faced by over 2 Billion people across the globe. But why does this happen when 70% of the Earth's surface is made up of water? How can we help save water? Joel Prakash Stephen video https://cdn.kastatic.org/googleusercontent/ZCdwTudJg6e6n-P2gsaUborP4izvMsGo71pvEVlX9dNYWcLXcP7VHkWpn2grt4TUP1KoJLQP9NswyHBuBLSFTBw Water Water scarcity is a major problem faced by over 2 Billion people across the globe. But why does this happen when 70% of the Earth's surface is made up of water? How can we help save water? https://cdn.kastatic.org/ka-youtube-converted/Dozbgnftdao.mp4/Dozbgnftdao.mp4 254 Earth's place in the solar system https://www.khanacademy.org/science/ap-college-environmental-science/x0b0e430a38ebd23f:earth-systems-and-resources/x0b0e430a38ebd23f:earths-air-and-water/e/earths-air-and-water 2025-08-08T21:39:42.49220884Z Earth's air and water Apply your understanding of Earth's air and water in this set of free practice questions aligned to AP standards. exercise https://www.khanacademy.org/science/middle-school-earth-and-space-science/x87d03b443efbea0a:earth-in-space/x87d03b443efbea0a:earths-place-in-the-universe/v/earths-place-in-the-universe 2024-01-04T21:44:22.995765104Z Earth's place in the universe Humans have used models to understand Earth's place in the universe. The geocentric model, placing Earth at the center, was replaced by the heliocentric model, with the sun at the center. This change better explains the movement of celestial bodies and shows that Earth's rotation causes the sun's apparent motion. Khan Academy video https://cdn.kastatic.org/ka_thumbnails_cache/367f5f88-2954-4708-a8a2-1ea2aa569771_1280_720_base.png Earth's place in the universe Humans have used models to understand Earth's place in the universe. The geocentric model, placing Earth at the center, was replaced by the heliocentric model, with the sun at the center. This change better explains the movement of celestial bodies and shows that Earth's rotation causes the sun's apparent motion. https://cdn.kastatic.org/ka-youtube-converted/Pv0Re0YEEq0.mp4/Pv0Re0YEEq0.mp4 294 Earth's place in the solar system https://www.khanacademy.org/science/strengthened-shs-earth-and-space-science-1/x006d5d274c051fd7:origin-and-structure-of-the-earth/x006d5d274c051fd7:earth-s-place-in-the-solar-system/v/the-sun-s-energy-and-earth-s-weather 2025-07-16T22:11:44.585720097Z The Sun's energy and Earth's weather The Sun powers Earth's weather by heating the atmosphere and hydrosphere unevenly. This energy drives the water cycle, creates wind through changes in air pressure, and fuels cloud formation and storms. Greenhouse gases help trap heat, keeping Earth warm enough for life while allowing weather systems to constantly shift and change. Mahesh Shenoy video https://cdn.kastatic.org/ka_thumbnails_cache/f5d9cc36-9bdf-424a-b817-10ad6a472ff0_1280_720_base.png The Sun's energy and Earth's weather The Sun powers Earth's weather by heating the atmosphere and hydrosphere unevenly. This energy drives the water cycle, creates wind through changes in air pressure, and fuels cloud formation and storms. Greenhouse gases help trap heat, keeping Earth warm enough for life while allowing weather systems to constantly shift and change. https://cdn.kastatic.org/ka-youtube-converted/JMaqaspDpr0.mp4/JMaqaspDpr0.mp4 374 Earth's place in the solar system https://www.khanacademy.org/humanities/oer-project-big-history/xc3079f0f2dd307e4:life/xc3079f0f2dd307e4:complexity-of-life-on-earth-3-1/a/article-the-thresholds-life-on-earth 2025-08-13T00:49:52.439041008Z The Thresholds: Life on Earth How did life emerge on a planet that started out as a fiery mass with molten rivers and toxic gas? Earth's location, water, and complexity hold the keys to the answer. article https://www.khanacademy.org/science/strengthened-shs-earth-and-space-science-1/x006d5d274c051fd7:origin-and-structure-of-the-earth/x006d5d274c051fd7:earth-s-place-in-the-solar-system/e/what-allows-life-to-be-sustained 2026-04-07T22:23:57.656416987Z What allows life to be sustained? Explore how air, water, soil, sunlight, plants, animals, and balance among Earth systems work together to sustain life on our planet. Yajurva Joshi exercise