The universe tells us its story mainly through light and other ... 300,000 kilometers per second. How long does light take to reach us from familiar objects? Let's take a quick tour of the solar ...

Light bounces or reflects off most objects, but not everything. When light hits your eye, it actually goes right into it through the opening at the front. The eye then sends signals to the brain.

When we observe distant celestial objects ... really as reddish as it appears? Or does the star merely look reddish, since ...