Ecosystems
Scientists Say: Decay
This word can refer to rotting flesh or the transformation of radioactive atoms.
HS-PS1-8
Develop models to illustrate the changes in the composition of the nucleus of the atom and the energy released during the processes of fission, fusion, and radioactive decay.
More Stories in HS-PS1-8
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AnimalsTraces from nuclear-weapons tests offer clues to whale sharks’ ages
Traces left by nuclear-bomb testing in the 1950s and ‘60s can help researchers learn how old a whale shark is.
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SpaceBlack hole mega-burp was truly explosive
Long, long ago, in a galaxy far, far away, a black hole blasted out 100 billion times as much energy as our sun ever will. One word for that: Wow!
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EarthExplainer: Understanding geologic time
Geologic time is unimaginably long. Geologists puzzle it out using a calendar called the Geologic Time Scale.
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EarthExplainer: Where fossil fuels come from
Despite one oil company famously using an Apatosaurus as its logo, oil, gas and coal don’t come from dinosaurs. They do, however, come from a long time ago.
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PlanetsHow Earth got its moon
How did our moon form? Scientists are still debating the answer. It may be the result of some one big impact with Earth — or perhaps many small ones.
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Scientists consider how to visit the closest exoplanet
Even at only a little more than four light-years away, a trip to our closest exo-world could take some tens of thousands of years — unless we’re willing to settle for virtual visits.
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ArchaeologyThe first farmers were two groups, not one
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EarthHelium discovery blows away shortage worries
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ArchaeologyNeandertals: Ancient Stone Age builders had tech skills
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