Photos: Smoke from Canadian wildfires creates eerie views as it moves across U.S. Northeast

Millions of Americans woke up to orange skies Wednesday as thick smoke from wildfires in Canada moved across the U.S. Northeast, spawning air quality warnings from Massachusetts to Washington, D.C.

In New York, air pollution reached record — and dangerous — levels, putting the city atop the world’s worst for air quality. State and local officials told residents to mask up and stay indoors, but many have questions about how the smoke will affect them, and what is and isn’t safe to do right now.