Johannes Kepler Astronomy

German mathematician and astronomer, Johannes Kepler was born December 27, 1571 in Regensburg, Germany. Kepler formulated three laws of planetary motion, introducing the prediction that the orbits of the planets would be ellipses.

The first law states that the shape of each planet's orbit is an ellipse with the sun at one focus. The sun is thus off-center in the ellipse and the planet's distance from the sun varies as the planet moves through one orbit.

The second law specifies quantitatively how the speed of a planet increases as its distance from the sun decreases. If an imaginary line is drawn from the sun to the planet, the line will sweep out areas in space that are shaped like pie slices. When the planet is far from the sun and moving slowly, the pie lice will be long and narrow; when the planet is near the sun and moving fast, the pie slice will be short and fat.

The third law is a relation between the average distance of the planet from the sun (the semimajor axis of the ellipse) and the time to complete one revolution around the sun (the period): the ratio of the cube of the semimajor axis to the square of the period is the same for all the planets including the earth.

Benjamin Banneker Inventor

At age 58, Banneker began the study of astronomy and was soon predicting future solar and lunar eclipses. He compiled the ephemeris, or information table, for annual almanacs that were published for the years 1792 through 1797. "Benjamin Banneker's Almanac" was a top seller from Pennsylvania to Virginia and even into Kentucky.

Daniel Bernoulli Physics- Aerodynamics

Daniel Bernoulli, 1700-1782, was a mathematician, physicist, and physician and has often been called the first mathematical physicist.

Bernoulli's principle

The physical principle formulated by Daniel Bernoulli that states that as the speed of a moving fluid (liquid or gas) increases, the pressure within the fluid decreases.

His greatest work was his Hydrodynamica (1738), which included the principle now known as Bernoulli's principle , and anticipated the law of conservation of energy and the kinetic-molecular theory of gases developed more than 100 years later. He also made important contributions to probability theory, astronomy, and the theory of differential equations

Alexander Graham Bell Inventor

Bell was born in Edinburgh, Scotland on March 3, 1847

Alexander Graham Bell, who invented one of the most significant domestic device of today – the Telephone.

Alexander Graham Bell is most well known for inventing the telephone. He came to the U.S as a teacher of the deaf, and conceived the idea of "electronic speech" while visiting his hearing-impaired mother in Canada. This led him to invent the microphone and later the "electrical speech machine" -- his name for the first telephone.

Nicolas Copernicus Astronomy

Born in 19 Feb 1473 Nicolaus Copernicus is said to be the founder of modern astronomy . He Discovered that the Earth is not in the center of the Universe but it circles the Sun. spinning on its axis once daily, revolves annually around the sun.

Copernicus had a clear, mathematical mind, and acquired a great knowledge of astronomy. He was not satisfied with the ancient system of the world The teachings of Copernicus may be reduced to two fundamental propositions. One is, that the earth makes a complete revolution on its axis every day, occasioning an apparent diurnal revolution of the heavens. The second is, that the sun, and not the earth, is the centre of motion; and that all the planets, of which the earth is the third in the order of distance, revolve around the central sun.

Albert Einstein Physics

Einstein received the Nobel Prize in 1921 for his 1905 work on the photoelectric effect.

After 1905, Einstein continued working in all three of his works in the 1905 papers. He made important contributions to the quantum theory, but increasingly he sought to extend the special theory of relativity to phenomena involving acceleration. The key to an elaboration emerged in 1907 with the principle of equivalence, in which gravitational acceleration was held a priori indistinguishable from acceleration caused by mechanical forces; gravitational mass was therefore identical with inertial mass.

By 1911, Einstein was able to make preliminary predictions about how a ray of light from a distant star, passing near the Sun, would appear to be attracted, or bent slightly, in the direction of the Sun's mass. At the same time, light radiated from the Sun would interact with the Sun's mass, resulting in a slight change toward the infrared end of the Sun's optical spectrum. At this juncture Einstein also knew that any new theory of gravitation would have to account for a small but persistent anomaly in the perihelion motion of the planet Mercury

About 1912, Einstein began a new phase of his gravitational research, with the help of his mathematician friend Marcel Grossmann, by phrasing his work in terms of the tensor calculus of Tullio Levi-Civita and Gregorio Ricci-Curbastro. The tensor calculus greatly facilitated calculations in four-dimensional space-time, a notion that Einstein had obtained from Hermann Minkowski's 1907 mathematical elaboration of Einstein's own special theory of relativity. Einstein called his new work the general theory of relativity.

Thomas Alva Edison Inventor

Born in 1847 in Milan, Ohio, Edison held 1,093 patents, including those for the incandescent electric lamp, the phonograph, the carbon telephone transmitter, and the motion-picture projector. He also created the world's first industrial research laboratory in October 1878.

The first great invention developed by Edison in Menlo Park was the tin foil phonograph. The first machine that could record and reproduce sound created a sensation and brought Edison international fame. Edison toured the country with the tin foil phonograph, and was invited to the White House to demonstrate it to President Rutherford B. Hayes in April 1878.

Edison next undertook his greatest challenge, the development of a practical incandescent, electric light. The idea of electric lighting was not new, and a number of people had worked on, and even developed forms of electric lighting. But up to that time, nothing had been developed that was remotely practical for home use. Edison's eventual achievement was inventing not just an incandescent electric light, but also an electric lighting system that contained all the elements necessary to make the incandescent light practical, safe, and economical. After one and a half years of work, success was achieved when an incandescent lamp with a filament of carbonized sewing thread burned for thirteen and a half hours. The first public demonstration of the Edison's incandescent lighting system was in December 1879, when the Menlo Park laboratory complex was electrically lighted.

One of his famous sayings was "Genius is 1 percent inspiration and 99 percent perspiration."

Lewis Howard Latimer Chemistry

Lewis Howard Latimer was born in Chelsea, Massachusetts on September 4, 1848.

Lewis Howard was a pioneer in the development of the electric light bulb, was the only Black member of Thomas A. Edison's research team of noted scientists. While Edison invented the incandescent bulb, it was Latimer, a member of the Edison Pioneers, and former assistant to telephone inventor Alexander Graham Bell, who developed and patented the process for manufacturing the carbon filaments. After co-inventing an electric lamp 1881, Latimer went on to invent a cheap method for producing long-lasting carbon light-bulb filaments 1882.

Other Latimer patents included a 'Water Closet for Railroad Cars' 1874, 'Apparatus for Cooling and Disinfecting' 1886, and 'Locking Rack for Hats, Coats, and Umbrellas' in 1896.