Grades 9-12 or Adult Sophisticated Learner
Investigating life on Earth has shown us that all living things need certain elements for their cellular processes, such as growth and metabolism. For instance, the CHNOPS elements (carbon, hydrogen, nitrogen, oxygen, phosphorus, and sulfur) are known to be part of every living thing. They make up most of the proteins, fats, nucleic acids, and carbohydrates that life uses. There are also lots of other elements, especially lots of the metals, that are needed by living things. All of these ingredients for life as we know it work kind of like a recipe, where you have to put the ingredients together in the right way to make the recipe work. So if we want to understand how life works, it’s important for us to know where the ingredients are and when they’re put together in the right way for life.
Fossil evidence shows life on Earth thriving well over 3.5 billion years ago. This implies that the ingredients for life were available very early in the history of Earth. We know that water, with both hydrogen and oxygen, was available back then based on the evidence left in the rock record. The CHNOPS elements along with a lot of metals and other important elements for life were present in the rocks of the crust and mantle of Earth, back then as well as now. This tells us that the ingredients for life have always been available on Earth.
We know that Earth is pretty good at recycling the elements that are present at the surface through processes like plate tectonics and volcanism. Plate tectonics are when the large plates of rock that make up the crust shift around and sometimes create new mountains or drive old rock down into the mantle. Volcanism includes all of the processes that make volcanoes and cause them to erupt. While plate tectonics can send some elements down into the mantle and bring new elements up when forming mountains, volcanism can bring some elements back to the surface in lava as well as to the atmosphere through the gases that come out during eruptions. We also know that the breakdown of rocks, known as weathering, is important for getting the ingredients for life out of rocks and into the soil and the oceans. A lot of things drive weathering, but the movement of water (in the hydrological cycle) is one of the most powerful on Earth. Elements like carbon and phosphorus become available for life due to water breaking down rocks.
The next important thing is finding the places where the ingredients for life are brought together in the right ways. We’re really lucky to have an active planet, because having lots of different kinds of environments means there’s lots of places where different ingredients can be brought together and made useful for life. For instance, high temperature places like hot springs and hydrothermal vents can make a lot of metals available for life. Glaciers breaking down rocks as they move can make nutrient rich soils. The oxygen in the atmosphere can actually react with the rocks at the surface to make chemical molecules that are useful for life. sunlight itself can cause a lot of the ingredients for life to come together in a way that make them more useful for living things.
Disciplinary Core Ideas
ESS1.C: The History of Planet Earth: Continental rocks, which can be older than 4 billion years, are generally much older than the rocks of the ocean floor, which are less than 200 million years old. (HS-ESS1-5) Although active geologic processes, such as plate tectonics and erosion, have destroyed or altered most of the very early rock record on Earth, other objects in the solar system, such as lunar rocks, asteroids, and meteorites, have changed little over billions of years. Studying these objects can provide information about Earth’s formation and early history. (HS-ESS1-6)
ESS2.C: The Roles of Water in Earth’s Surface Processes: The abundance of liquid water on Earth’s surface and its unique combination of physical and chemical properties are central to the planet’s dynamics. These properties include water’s exceptional capacity to absorb, store, and release large amounts of energy, transmit sunlight, expand upon freezing, dissolve and transport materials, and lower the viscosities and melting points of rocks. (HS-ESS2-5)
PS1.A: Structure and Properties of Matter: Each atom has a charged substructure consisting of a nucleus, which is made of protons and neutrons, surrounded by electrons. (HS-PS1-1) The periodic table orders elements horizontally by the number of protons in the atom’s nucleus and places those with similar chemical properties in columns. The repeating patterns of this table reflect patterns of outer electron states. (HS-PS1-1, HS-PS1-2)
PS1.B: Chemical Reactions: Chemical processes, their rates, and whether or not energy is stored or released can be understood in terms of the collisions of molecules and the rearrangements of atoms into new molecules, with consequent changes in the sum of all bond energies in the set of molecules that are matched by changes in kinetic energy. (HS-PS1-4, HS-PS1-5)
LS1.A: Structure and Function: Systems of specialized cells within organisms help them perform the essential functions of life. (HS-LS1-1)
LS1.C: Organization for Matter and Energy Flow in Organisms: The process of photosynthesis converts light energy to stored chemical energy by converting carbon dioxide plus water into sugars plus released oxygen. (HS-LS1-5) *The sugar molecules thus formed contain carbon, hydrogen, and oxygen: their hydrocarbon backbones are used to make amino acids and other carbon-based molecules that can be assembled into larger molecules (such as proteins or DNA), used for example to form new cells. (HS-LS1-6)
LS4.C: Adaptation: Changes in the physical environment, whether naturally occurring or human induced, have thus contributed to the expansion of some species, the emergence of new distinct species as populations diverge under different conditions, and the decline – and sometimes the extinction – of some species. (HS-LS4-6, HS-LS4-5)
ESS1.A: The Universe and Its Stars: Other than the hydrogen and helium formed at the time of the big bang, nuclear fusion within stars produces all atomic nuclei lighter than and including iron, and the process releases electromagnetic energy. Heavier elements are produced when certain massive stars achieve a supernova stage and explode. (HS-ESS1-2, HS-ESS1-3)
ESS2.B: Plate Tectonics and Large-Scale System Interactions: Plate tectonics is the unifying theory that explains the past and current movements of the rocks at Earth’s surface and provides a framework for understanding its geologic history.(HS-ESS2-1) *The radioactive decay of unstable isotopes continually generates new energy within Earth’s crust and mantle, providing the primary source of the heat that drives mantle convection. Plate tectonics can be viewed as the surface expression of mantle convection. (HS-ESS2-3)
ESS2.E: Biogeology: The many dynamic and delicate feedbacks between the biosphere and other Earth systems cause a continual co-evolution of Earth’s surface and the life that exists on it. (HS-ESS2-7)
Patterns: Empirical evidence is needed to identify patterns. (HS-ESS1-5)
Stability and Change: Much of science deals with constructing explanations of how things change and how they remain stable. (HS-ESS1-6)
Big Ideas: Life began on Earth between 3.5 and 3.8 billion years ago. All life forms require carbon, hydrogen, nitorgen, oxygen, phosphorous and sulphur (CHNOPS). Because CHNOPS are vital to life on Earth, astrobiologist look for these elements elsewhere in the universe when looking for life beyond Earth. The formation materials for Earth contained a high amount of water. Plate tectonics and volcanic activity put much of the water onto the surface of Earth along with other carbon, nitrogen, and sulphur. Weathering and erosion brought phosphorous and sulphur into the oceans, which all the necessary ingredients for life. Astrobiologist use knowledge of CHNOPS to look for and study life beyond Earth.
Boundaries: In this grade band, students use the periodic table as a model to predict the relative properties of elements. Examples of properties that could be predicted from patterns could include reactivity of metals, types of bonds formed, numbers of bonds formed, and reactions with oxygen. Focus is on main group elements. (HS-PS1-1)
3-12 A Guide to Collecting Micrometeorites. This lesson has complete directions for the collection, identification and measurement of micrometeorites. It could be used as a rich hands-on investigation of the solar system origins, the formation of the Earth, the interaction of Earth and space and/or the delivery of the ingredients necessary for life (CHNOPS). ScienceSouth.org/NASA. http://www.sciencesouth.org/wp-content/uploads/2011/06/2016VF-A-Guide-to-Collecting-Micrometeorites-JMM-1.pdf
5-12 Exploring Meteorite Mysteries: Changes Inside Planets (11.1). In this lesson, students conduct an experiment using gelatin and food that illustrates planetary differentiation. Earth is differentiated into core, mantle and crust. Differentiation is a critical step in the formation of a habitable planet Earth. NASA. https://er.jsc.nasa.gov/seh/Exploring_Meteorite_Mysteries.pdf
5-12 Life on Earth. Although the exact process by which life formed on Earth is not well understood, the origin of life requires the presence of carbon-based molecules, liquid water and an energy source. Because some Near-Earth Objects contain carbon-based molecules and water ice, collisions of these object with Earth have significant agents of biologic as well as geologic change.
6-12 Astrobiology Math. This collection of math problems provides an authentic glimpse of modern astrobiology science and engineering issues, often involving actual research data. Students explore concepts in astrobiology through calculations. Relevant topics include The Largest Known Extraterrestrial Molecules (page 11) and The Miller-Urey Experiment: Complex Organic Molecules (page 13). NASA. https://www.nasa.gov/pdf/637832main_Astrobiology_Math.pdf
7-12 Exploring Meteorite Mysteries: Changes inside planets. This activity explores the concept of differentiation through a food model with gelatin. Differentiation is a critical step in the formation of a habitable planet Earth. This activity is part of a multi-lesson unit on meteorites, called Meteorite Mysteries. JSC/NASA. https://er.jsc.nasa.gov/seh/Exploring_Meteorite_Mysteries.pdf#page=125
9-12 New NASA Research Shows Giant Asteroids Battered Early Earth. New research shows that more than four billion years ago the surface of Earth was heavily reprocessed – or melted, mixed, and buried – as a result of giant asteroid impacts. A new terrestrial bombardment model, calibrated using existing lunar and terrestrial data, sheds light on the role asteroid collisions played in the evolution of the uppermost layers of the early Earth during the geologic eon called the “Hadean” (approximately 4 to 4.5 billion years ago).