Presentation on theme: "The Habitable Planet 7.9: Earth and Space – The student knows components of our solar system. 7.9A: The student is expected to analyze the characteristics."— Presentation transcript:
1 The Habitable Planet7.9: Earth and Space – The student knows components of our solar system.7.9A: The student is expected to analyze the characteristics of the objects in our solar system that allow life to exist such as the proximity of the Sun, the presence of water, and composition of the atmosphere.
2 Traditional understanding of the “habitable zone” Source: NASA
3 How Earth Supports Life Proximity to SunAtmospheric composition and layeringGravityRelationship with MoonOceansWhat other conditions support life on Earth?
4 Proximity to SunEarth is the third closest planet to the Sun, approximately 150 million kilometers away.Earth is just close to and far enough away from the Sun (a star) to be warm.
5 Earth’s Atmosphere (composition) 78% nitrogen21% oxygen – almost all plant produced1% other gases (argon, carbon dioxide, trace elements)The atmosphere has elements essential for building the chemical compounds to support life (carbon, hydrogen, oxygen, nitrogen, phosphorus, sulfur).
6 Earth’s Atmosphere (layers that directly affect life) Troposphere: lowest layer, where weather occurs, gets cooler higher up in this layerStratosphere: harmful UV rays absorbed (ozone layer), gets warmer the higher up in this layer
7 Ozone in the stratosphere absorbs most of the harmful UV rays.
9 Earth’s large constant mass allows for gravity which holds matter to Earth.
10 Oceans Largest source of water that supports marine plants and animals Why is water essential?
11 Plate Tectonics: motions of the Earth’s lithospere Helps to create magnetic fields that deflect harmful solar winds that could damage DNAHelps to replenish the essential elements for lifeCarbon – especially important for the carbon cycleNitrogenHydrogenPhosphorusSulfurSources: