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North America's smoky skies | | Do your skies look hazy? Are your sunsets very orange, or layered-looking, or does the sun or moon look orange while high in the sky? If you're in the northern U.S. or Canada, the reason is still wildfire smoke. | | |
What are rare earth elements? | | Most of us use rare earth elements every day without knowing it. These little-known and fascinating elements make modern electronics possible. | | |