A lunar lander has completed its two-week mission and sent spectacular sunset images as a "final goodbye" back to Earth. The Blue Ghost Mission ... Moon's surface as the sun goes down.

They occur when electrically charged particles from the sun collide with gases in the Earth's atmosphere, creating vibrant streaks of blue, green, pink and violet dancing across the night sky.

Carry a compass to figure out where the sun will rise and set ... Think about the sky. Do you want a lot or a little of it? A clear blue sky might best reflect the character of one plain, a ...

The whole dome of night sky was awash with color: cascades of yellow-green and blushes of crimson fanning from a darker point high overhead. As they fell in broad rays, they shifted and changed in ...