Einstein's observation on gravity proved right

"The speed of gravity matches the speed of light." This theory by Albert Einstein has finally been validated by astronomers who calculated and measured fundamental forces of nature with the help of a rare planetary alignment. Einstein, who formulated the basic theories about space, time and relativity, had assumed that gravity moved with the speed of light,(about 300,000 km per second).However until now, no attempts were made to prove this theory with actual physical measurement.

Gravity shapes the structures and evolution of stars, galaxies and the entire universe. The trajectories of bodies in the solar system are determined by the laws of gravity, while on earth all bodies have a weight, or downward force of gravity, proportional to their mass, which the Earth's mass exerts on them. Gravity is measured by the acceleration that it gives to freely falling objects. At the Earth's surface the acceleration of gravity is about 9.8 metres per second square. Thus, for every second, an object is in free fall, its speed increases by about 9.8 metres per second.

The work of Isaac Newton and Albert Einstein dominate the development of gravitational theory. Einstein's career was very interesting. In 1905, he published four papers - Brownian motion; the photoelectric effect; finding the size of molecules and relativity in a German Physics monthly. In 1914, he moved to Berlin, the Prussian Academy of Sciences. In 1916, he published the general theory of relativity in Annalen der Physik. In 1919, the Royal society of London verified the predictions made in Einstein's general theory of relativity. In 1921, he won the Noble prize for physics for the photoelectric law and work in the field of theoretical physics. In 1933, he renounced German citizenship and moved to U.S.A. Later, he accepted a full time position as a foundation member of the school of mathematics at the new Institute for advanced study in Princeton, New Jersey. In 1939, he wrote to President F.D.Roosevelt urging "watchfulness and if necessary, quick action" in atomic bomb research, marking the beginning of Manhattan Project.

Newton's classical theory of gravitational force held sway from his Principia, published in 1687, until Einstein's work in the early 20th century. The major significance of Einstein's theory is its radical conceptual departure from classical theory and its implications for further growth in physical thought.

Scientists Edward B. Fomalout of the National Radio Astronomy observatory and Sergei Kopeikain of the University of Missouri took up the task of measuring the velocity of gravity with the help of planet Jupiter. They measured the apparent change in the position of a distant quasar when its radio waves passed by Jupiter and were deflected by the gravitational field of the planet. The final calculation proved that gravity does indeed travel at the speed of light. The specific position of Jupiter that enables this particular measurement occurs only once a decade.