When it comes to sunlight’s impact on the skin, people usually think of ultraviolet (UV) light, the invisible light that causes sunburn. However, sunlight also includes the visible light spectrum that the naked eye can see, that is, red, orange, yellow, green, blue, indigo and violet light. What Does Blue Light Mean?Blue light is short in wavelength and high in energy. Aside from the sun, it can also come from artificial sources like electronic devices and indoor lighting. “Blue light is wha ...read more
St. Patrick’s Day is right around the corner, and with it comes tales of mischievous leprechauns and the pots of gold that they guard at the end of rainbows.You may already know that there is no “end” of a rainbow — science tells us that their arch shape is simply an illusion. In reality, while those of us on the ground can only see the light reflected by raindrops above the horizon, viewers in aircraft can sometimes see a rainbow’s full, 360-degree circle.But that doesn’t mean the m ...read more
The Greek historian Herodotus reported over 2,000 years ago on a misguided forbidden experiment in which two children were prevented from hearing human speech so that a king could discover the true, unlearned language of human beings.Scientists now know that human language requires social learning and interaction with other people, a property shared with multiple animal languages. But why should humans and other animals need to learn a language instead of being born with this knowledge, like ...read more
The Han Chinese court welcomed Western trade for one of the first times in its history around 2,000 years ago. What its courtiers couldn't have imagined was that they were laying the foundations for one of the oldest, largest and longest-lasting systems of trade in the world.That said, the ancient Silk Road system endured the formation and the fall of countless cultures and civilizations throughout its 1,600-year existence, emerging from almost every experience bigger and better than before.So, ...read more
This article was originally published on March 14, 2021.March 14 is Pi Day — so what’s with that? A holiday to celebrate a number (and eat lots of pie)? Well, yes, but pi is not just any number. There is much more to the pi day meaning than that.Why Is Pi Day Celebrated on March 14?Pi is simply (well, it’s not really simple, but bear with me) the ratio of the circumference to the diameter of a circle. If you take a circle — any circle — and divide its circumference by its diameter, y ...read more
Author Vishay SinghPosted on Categories Discover Magazine
