Here’s how it works. The speed of light traveling through a vacuum is exactly 299,792,458 meters (983,571,056 feet) per second. That's about 186,282 miles per second — a universal constant ...

Learn more› By Teresa Carr Using a wand or scary-looking mask to bathe your face in red light is all the rage for helping to make skin look and feel better. But another use for red light therapy ...

Full-face LED masks like this one can cost up to several thousand U.S. dollars. The application of red light can stimulate collagen production and blood circulation, and even reduce signs of aging.

Social media posts showcasing the use of red light therapy devices at home are sparking interest in this trendy skin treatment — but does it deliver on its promises? While some studies have ...