Today's (29th February 2016) Google Doodle celebrates Leap Day! Why is there a Leap Day? Google Shows Doodle for Leap Year 2016
The 29th of February only happens every four years. This is to keep our calendar in sync with the rotation of the Earth around the sun. Without Leap Day, we'd be out of sync by about six hours per year.
Leap Day happens every four years unless that year is divisible by 100. If you were around in 1900, you would have missed out on the magic of February 29.
Anyone born on Leap Day, will not get chance to celebrate their birthday every year.
Today (8th February, 2016) the Search Engine Google is showing a Doodle for the 182nd Birthday of Dmitri Mendeleev in many countries.
Dmitri Mendeleev was a Russian chemist and inventor. He formulated the Periodic Law, created his own version of the periodic table of elements, and used it to correct the properties of some already discovered elements and also to predict the properties of eight elements yet to be discovered.
Around 400 BC, the ancient Greeks organized the worldly elements into four groups: air, water, earth, and fire. In the seventeenth century, Robert Boyle explained the material world in terms of elements, mixtures, and compounds. And in 1869, Dmitri Mendeleev made sense of the 56 elements known at the time, showing how they related to each other in a distinct pattern. His periodic table let elements fall into "periods" according to atomic mass and valence (the power that determines how they combine).
Scholars had attempted to organize the elements into a table before, but Mendeleev's work extended beyond mere chart-making. Mendeleev used the logic of his table to argue for the existence of yet-to-be discovered elements (like gallium and germanium), and even to predict their behaviors. Some of these predictions were wrong, but the basic principles behind his periodic organization continue to stand at the foundation of modern chemistry. The periodic table of the elements (now with 118 elements and counting) adorns science classrooms worldwide.
