What Causes a Mirage?
What Causes a Mirage? Desert travelers often tell of seeing distant pools of water, only to have the water disappear when they drew near. Those vanishing images are...
Read More
Why Do Sunsets Look Red?
Why Do Sunsets Look Red? In the evening, when the sun is near the horizon, the sun may look red, and the sky may glow with the warm colors of a sunset. Of course, the...
Read More
How Many Stars Are There in the Universe?
How Many Stars Are There in the Universe? No one knows how many stars there are in the universe. We cannot see all the stars, much less count them. It is estimated that...
Read More
What Are Clouds Made Of?
Clouds are made up of very tiny drops of water or tiny crystals of ice that float in the air. Clouds form when warm air, containing moisture evaporated from the...
Read More
What Are the Northern Lights?
What Are the Northern Lights? People in northern countries sometimes see colorful displays of flickering, glowing light in the night sky. This colored glow is the...
Read More