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.
- Physics
Explainer: Radiation and radioactive decay
Like clockwork, radioactive forms of some elements shed parts of themselves as they attempt to become nonradioactive.
- Physics
Scientists Say: Neutron
Neutrons are one of the main building blocks of atoms and have no electric charge.
- Earth
Not one, but two asteroids might have ended the age of dinosaurs
A craterlike structure found off the coast of West Africa might have been formed by an asteroid that struck around the time dinosaurs went extinct.
- Animals
Great white sharks may be partly to blame for the end of megalodons
Zinc levels in shark teeth hint that megalodons and great whites competed for food — and great whites won.
- Chemistry
Scientists Say: Proton
These positively charged particles are important building blocks in atoms.
- Earth
Tiny gemstones show when Earth’s crust first started moving
Chemical hints observed in zircons suggest when the important process of plate tectonics first took off.
- Chemistry
Scientists Say: Decay
This word can refer to rotting flesh or the transformation of radioactive atoms.
- Animals
Tiny animals survive 24,000 years in suspended animation
Tiny bdelloid rotifers awake from a 24,000-year slumber when freed from the Arctic permafrost.
- Physics
Nuclear clocks are nearly here
More precise clocks could improve technologies such as GPS and help scientists test major ideas in science.
- Animals
Traces 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.
- Space
Black 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!
- Earth
Explainer: Understanding geologic time
Geologic time is unimaginably long. Geologists puzzle it out using a calendar called the Geologic Time Scale.
