Space.com on MSN

The search for life: A space science quiz

Kenna Hughes-Castleberry is the Content Manager at Space.com. Formerly, she was the Science Communicator at JILA, a physics ...
Live Science

Heart quiz: What do you know about the body's hardest-working muscle?

Your heart pumps blood from your head to your toes, provides cells with fresh oxygen, and removes waste products. Located in the middle of your chest and tilted slightly to the left, your heart pushes ...