Physics
Explainer: How the Doppler effect shapes waves in motion
The Doppler effect describes how waves are compressed or stretched when their source — or receiver — is moving.
Word of the Week
Psychology
Scientists Say: Trauma
No one experiences trauma the same way. Its effects can be physical or emotional. Immediate or delayed. Brief or long-lasting.
Explainers
Life
Explainer: What is an endangered species?
Threats such as climate change and habitat loss can put species at risk of going extinct. Different words describe that risk.
Analyze This
Planets
Analyze This: Some 5,000 planets orbit stars other than our sun
A new cache of confirmed exoplanet discoveries marks a milestone in planets found beyond our solar system.
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En Español
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Why these jumping toadlets get confused mid-flight
The tiny pumpkin toadlet tumbles when it jumps. Its ear canals may be too tiny to help the animal track its motion through the air.
