By definition, a black hole is a region where matter collapses to infinite density, and where, as a result, the curvature of space-time is extreme. ... Although many physicists doubted the existence of gravitational waves, physical evidence was presented when American researchers observed a binary pulsar system that was thought to consist of two neutron stars orbiting each other closely and rapidly. ... In other words, the stars were spiraling toward each other, and by the exact amount predicted if the system were losing energy by radiating gravity waves. ...

• Word Count: 3068
• Approx Pages: 12
• Grade Level: High School