#200 Why are plants green?
I learned this today. Plants are green because they absorb light in the wavelengths that are red and blue, while reflecting light […]
#199 What effect did the 1815 Mt. Tambora eruption have?
I learned this today. The 1815 Mt. Tambora eruption lowered global temperatures and caused the Year Without a Summer. Mt. Tambora is […]
#198 Why do the sun’s poles flip every 11 years?
I learned this today. The sun flips its magnetic field and its north south poles once every 11 years because its inner […]
#197 What is Jupiter’s Great Red Spot?
I learned this today. Jupiter’s Great Red Spot is a high-pressure region in the atmosphere that causes the largest anticyclonic storm in […]
#196 When did the CIA start?
I learned this today. The CIA was formed on September 18th, 1947. The idea behind some kind of agency to manage intelligence […]
#195 How do fiber optic cables work?
I learned this today. A fiber optic cable works by sending information encoded in a beam of light. Different technologies send information […]
#194 When did people start using tissues?
I learned this today. Paper tissues have been used for 1500 years in China, but the modern tissue was invented in 1924. […]
#193 How many times can you recycle something?
I learned this today. Glass and metal can be recycled indefinitely, but plastic can only be recycled once or twice and paper […]
#192 How does a pearl form?
I learned this today. A pearl forms in the shell of a mollusk when an irritant becomes trapped there and the mollusk […]
#191 What is Maslow’s Hierarchy of Needs?
I learned this today. Maslow’s hierarchy of needs is a universal classification system which has the most important needs at the bottom […]