A few of the greatest who have contributed tremendously to the world of science.
Edwin Hubble
With advanced technology, Hubble showed that some of the numerous distant, faint clouds of light in the universe were actually entire galaxies, just like ours. This discovery changed the pace for astronomers as to how they looked at our place in the universe. His greatest discovery was when he noticed the farther a galaxy is from Earth, the faster it appears to move away. This is referenced to the big bang, that ever since then, the universe has been expanding. Even a telescope was named after Hubble, orbiting the Earth since 1990, it has provided some of the greatest discoveries for us.
Albert Einstein
Einstein is considered the most influential physicist in the 20th century. 1905 is often considered Einstein's miracle year. He had published four papers - the photoelectric effect, the Brownian motion, special relativity, and the equivalence of matter and energy. This brought him to the attention within society, especially the acedemic world. These papers also included his famous equation: e=mc2, suggesting tiny particles of matter could be converted into huge amounxds of energy. In 1915, Einstein completed his theory of general relativity. He was convinced his theory was accurate because of the mathematical evidence. The theory also predicted that a measurable deflection of light around the sun when a planet orbited near the sun. Because his theory was later proved in observations during a solar eclipse, he was awarded the Nobel prize in physics. Another major accomplishment was Einstein's discovery of dark matter, types of matter in space that don't emit light and cannot be detected.