I learned this today. Smallpox was responsible for as many as 500 million deaths in the 20th century, but it was completely eradicated by December 1979. Smallpox is a disease caused by four orthopoxviruses. They are variola, vaccinia, cowpox, and monkeypox. Variola only infects humans while the other viruses can infect other animals as well. […]
#114 What happened to smallpox? Read More »
I learned this today. Thomas Edison used thin strips of bamboo in his early light bulbs because carbonized bamboo has a very high electrical resistance. When Edison started trying to improve the light bulb, there were two basic forms of light available: arc lights and incandescent lights. An arc light is one that makes light
#113 Why did Thomas Edison use bamboo in his light bulb? Read More »
I learned this today. Evergreen trees keep their leaves for longer because they have evolved to survive in colder areas with less yearly sunlight. An evergreen tree is a tree that doesn’t lose its leaves all at once in the way a deciduous tree does. The leaves do fall off, but when they are old,
#111 Why don’t evergreen trees lose their leaves in the winter? Read More »
I learned this today. Graphene is a one-atom-thick layer of carbon atoms arranged in a hexagonal lattice. It is incredibly thin and incredibly strong. In 1859, Benjamin Brodie noticed that graphite oxide contained lots of layers. In 1947, P. R. Wallace published a paper on the band structure of graphite and theorized that a single
#109 What is graphene and why is it so important? Read More »
I learned this today. The International Prototype of the Kilogram, kept in Paris, is not accurate enough to be the standard for all kilograms around the world. Different measures for different things have been used around the world since people began measuring things. These measurements were usually related to the human body or common things
#108 Why is the official kilogram in France no longer used? Read More »
I learned this today. The Milky Way Galaxy orbits the barycenter of the Local Group. The barycenter is the center of mass of two bodies that orbit each other. It is the point that they orbit around. The word comes from Ancient Greek and means “heavy center”. When two objects orbit each other, there is
#106 What does the Milky Way Galaxy orbit? Read More »
I learned this today. Light can’t escape from a black hole because of the curvature of space caused by gravity. In physics, gravity is the weakest of the four fundamental forces. The forces are gravity, the electromagnetic force, and the strong and weak forces that exist in atoms. Isaac Newton described gravity as a force
#101 Why can’t light escape from a black hole? Read More »
I learned this today. Flight or fight, the stress response, was first described by Walter Bradford Cannon in 1915. In 1915, Cannon published Bodily changes in pain, hunger, fear and rage. He noticed that when cats were threatened, their bodies released the hormone adrenaline / epinephrine, which lead to a series of other bodily changes.
#100 Who came up with the phrase “flight or fight”? Read More »
I learned this today. Cold fusion is not possible because atoms repel each other and thermo energy on the scale of millions of degrees is necessary to overcome this repelling force and drive them together. Nuclear fusion is the reaction that takes place in stars. It is the process by which they burn their fuel,
#98 Why is cold fusion not possible? Read More »
I learned this today. Absolute zero is zero Kelvin, which is -273.15℃, but it is impossible to reach. Absolute zero is considered to be the lowest temperature possible. At this point, there is no energy left in a solid. In any object, the molecules are moving. In my fingers. In the keyboard I am typing
#93 Is it possible to get absolute zero? Read More »
