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May 1, 1514
Nicolaus Copernicus
(1473–1543) Astronomer Nicolaus Copernicus identified the concept of a heliocentric solar system, in which the sun, rather than the earth, is the center of the solar system -
Johannes Kepler
(1571-1630)German astronomer who discovered three major laws of planetary motion, conventionally designated as follows: (1) the planets move in elliptical orbits with the Sun at one focus; (2) the time necessary to traverse any arc of a planetary orbit is proportional to the area of the sector between the central body and that arc (the “area law”); and (3) there is an exact relationship between the squares of the planets’ periodic times and the cubes of the radii of their orbits (the “harmonic l -
Galileo
(1564–1642) The Starry Messenger, revealing his discoveries that the moon was not flat and smooth, but a sphere with mountains and craters. He found Venus had phases like the moon, proving it rotated around the sun. He also discovered Jupiter had revolving moons, which didn’t revolve around the earth -
Robet Hooke
(1635-1703) Robert Hooke looked at a sliver of cork through a microscope lens and noticed some "pores" or "cells" in it. Robert Hooke believed the cells had served as containers for the "noble juices" or "fibrous threads" of the once-living cork tree. He thought these cells existed only in plants, since he and his scientific contemporaries had observed the structures only in plant material. -
Willebrord Snellius
(1580–1626) Snell's law (also known as the Snell–Descartes law and the law of refraction) is a formula used to describe the relationship between the angles of incidence and refraction, when referring to light or other waves passing through a boundary between two different isotropic media, such as water, glass and air. -
Isaac Newton
published quantitative description of bodies in motion in three basic laws: 1) A stationary body will stay stationary unless an external force is applied to it; 2) Force is equal to mass times acceleration, and a change in motion is proportional to the force applied; and 3) For every action, there is an equal and opposite reaction. These three laws not only helped explain elliptical planetary orbits but nearly every other motion in the universe: how the planets are kept in orbit b -
Ben Franklin
(1706–1790) Inventor and proved that lightning is a form of electricity -
James Watt
(1736-1819) a Scottish inventor and mechanical engineer whose improvements to the Newcomen steam engine were fundamental to the changes brought by the Industrial Revolution in both his native Great Britain and the rest of the world. -
André-Marie Ampère
(1775-1836)Ampère to formulated his famous law of electromagnetism, called after him Ampère's law, that describes mathematically the magnetic force between two electrical currents. -
Amedeo Avogadro
(1776-1856) Avogadro's law states that equal volumes of gases, at the same temperature and pressure, contain the same number of molecules. -
Georg Ohm
(1789-1854) Using equipment of his own creation, Ohm found that there is a direct proportionality between the potential difference (voltage) applied across a conductor and the resultant electric current. This relationship is known as Ohm's law. -
Christian Doppler
(1803-1853) the changes in frequency of waves through a medium measured by an observer moving with respect to the waves' source. This has come to be known as the Doppler effect. -
James Prescott Joule
(1818-1889) He discovered that heat and mechanical energy are inter-convertible, and that transformations from one to the other occur in a fixed proportion, known as the mechanical equivalent of heat -
William Thomson, 1st Baron Kelvin
(1824–1907) Lord Kelvin helped develop the second law of thermodynamics and he invented the absolute temperature scale named after him. He was chief consultant for the laying of the first Atlantic cable (1857–58). His work in electricity and magnetism led to James Clerk Maxwell's theory of electromagnetism. He also contributed to the determination of the age of the Earth and the study of hydrodynamics. -
Heinrich Hertz
1857-1894 The great German physicist, Heinrich Hertz made possible the development of radio, television, and radar by proving that electricity can be transmitted in electromagnetic waves -
Nikola Tesla
(1856-1943) Serbian-American inventor Nikola Tesla was born in July of 1856, in what is now Croatia. He came to the United States in 1884, and briefly worked with Thomas Edison before the two parted ways. He sold several patent rights, including those to his alternating-current machinery, to George Westinghouse. His 1891 invention, the "Tesla coil," is still used in radio technology today. Tesla died in New York City on January 7, 1943. -
Albert Einstein
(1879-1955) Einstein completed the general theory of relativity, which he considered his masterpiece. He was convinced that general relativity was correct because of its mathematical beauty and because it accurately predicted the perihelion of Mercury's orbit around the sun, which fell short in Newton’s theory. General relativity theory also predicted a measurable deflection of light around the sun when a planet or another sun oribited near the sun.
