Without the work of intellectual giants like Einstein, Newton and Darwin, we might still be in the dark ages. But how many scientists still read the dust-ridden texts where these luminaries first expounded their theories? Thanks to the internet, you no longer have to hunt down these yellowing tomes in a moldy library vault. Here’s the story of 9 famous publications that spun the scientific world off its orbit. Above: "On the Revolutions of Heavenly Spheres" by Nicolaus Copernicus, 1543 Contrary to what your dog may think, you’re not the center of the universe. Copernicus, a Polish merchant's son, discovered that the sun is at the center of our solar system – the so-called heliocentric model – overturning the commonly accepted Earth-centric model introduced by Ptolemy in the 2nd Century A.D. "It was setting in stone the process of critical thinking, that the whole world doesn’t revolve around us," said astronomer Geoff Marcy of the University of California, Berkeley. Though Marcy and most astronomers haven't read the entirety of Copernicus's original text, it's valuable for its historical interest, he said. Copernicus waited until he was on his deathbed in 1543 to publish his work, De Revolutionibus Orbium Coelestium (On the Revolutions of Heavenly Spheres), written in Latin. It didn’t cause much of a fuss until Galileo took up the charge a century later.

"Dialogue Concerning the Two Chief World Systems" by Galileo Galilei, 1632 Few people took Copernicus seriously that the Earth orbited in a sun-centered solar system until Galileo revisited the idea in 1632, when he published his "Dialogue Concerning the Two Chief World Systems." He wrote his treatise (in Italian) as a dialogue between three characters: an academic named Salviati who supports the Copernican view, a philosopher named Simplicio who believes (simplistically) that the sun revolves around the Earth, and an intelligent layman named Sagredo who takes a neutral position. "People didn’t believe Copernicus -- he didn’t believe himself," said astronomer Geoff Marcy of UC Berkeley. "Galileo was the one who pushed the Copernican model." At the Dialogue’s conclusion, the character Simplicio admits “My mind feels a great repugnance to this,” and apparently the Catholic church felt the same. Galileo found himself before the Roman Inquisition, which convicted him of heresy, forcing to him to recant his views. His Dialogue was banned, and he lived under under house arrest until his death, but his scientific contribution long outlives him.

"Philosophiae Naturalis Principia Mathematica" by Isaac Newton, 1687 Isaac Newton was, unequivocally, a scientific rockstar. He described universal gravitation and most of classical mechanics, and shares credit with Gottfried Leibniz for developing differential and integral calculus. Newton's crowning work was his "Philosophiae Naturalis Principia Mathematica," Latin for "Mathematical Principles of Natural Philosophy." Known more commonly as the "Principia," the three-book work was published in 1687. The Principia provided the foundation for much of the physics that followed. Even though we now know Newtonian physics does not accurately describe the quantum world, it remains perfectly relevant for describing motion on the scale of, say, baseballs. "Physicists essentially never go back to the original," said theoretical physicist Lawrence Krauss, of Arizona State University. Still, "it's all based on that," he said.

"On the Origin of Species" by Charles Darwin, 1859 Charles Darwin had a few false starts training as a doctor and parson before joining the voyage that would lead him to his famous theory of evolution by natural selection. His 1859 book "On the Origin of Species by Means of Natural Selection, or the Preservation of Favoured Races in the Struggle for Life" underpins all of evolutionary biology. Commonly given the moniker, “survival of the fittest,” the theory of natural selection asserts that all species struggle for life in an environment of limited resources, and due to heritable differences among individuals, those most likely to survive and reproduce will pass their traits on to successive generations. The concept explains how new species form from a common ancestor. Others had previously proposed the idea of evolution, but Darwin’s book gave it a mechanism, backed up by extensive examples. "It was the overwhelming addition of all those examples that made it powerful," said biologist Gary Wessel of Brown University. While the field has evolved immensely since Darwin's day, his work remains its foundation.

"Micrographia" by Robert Hooke, 1665 Robert Hooke’s "Micrographia" explores his exquisite observations of life under the microscope. It was the Royal Society’s first publication, and the first to use the term ‘cell’ in biology. Written in 1665, the book contains Hooke’s elaborate copperplate engravings, including a close-up view of a flea (above) and other insects. "With a picture, you can quickly extract a tremendous amount of info," said biologist Gary Wessel of Brown University. Hooke’s descriptions of his microscopy subjects verge on poetic: "The Eyes of a Fly in one kind of light appear almost like a Lattice, drill'd through with abundance of small holes... In the Sunshine they look like a Surface cover'd with golden Nails; in another posture, like a Surface cover'd with Pyramids; in another with Cones." Hooke's work -- a blend of science and aesthetics -- opened up the vast world of life invisible to the naked eye.

"Gray’s Anatomy" by Henry Gray, 1858 You may know it as a TV show, but "Gray's Anatomy" was, and remains, a seminal medical textbook. There have been many versions, but the original, called "Anatomy: Descriptive and Surgical," was written by the British anatomist and surgeon Henry Gray in 1858. "It was the first time that somebody ever sat down and really comprehensively put together this kind of atlas of the human body," said medical student Lujia Zhang, who studies at UCLA and Charles Drew University. "Even right now, it’s far more detailed than most anatomy books." The anatomical artist Henry Vandyke Carter provided the book's illustrations and assisted Gray with dissections. Unfortunately, Gray died of smallpox at age 34, just three years after publishing it. The book soon became the standard reference for anatomy. Although medical students today learn much more modern technology such as CT or MRI imaging, many still use an updated version of Gray's Anatomy. The latest version, the 40th edition, was published in 2008. There's even a Gray's iPhone app now.

"Elements of Chemistry" by Antoine Lavoisier, 1789 Lavoisier has been called "the father of modern chemistry." His "Traité Élementaire de Chimie" (Elements of Chemistry), published in 1789, synthesized much of his most important work. "Lavoisier’s book was an elementary treatise on chemistry, yet it transformed the science," said chemistry historian Alan Rocke of Case Western Reserve University. "This book for the first time defined properly what a chemical element was." Lavoisier showed that the principle of conservation of mass applied to chemistry, and debunked the theory claiming that materials released a substance called 'phlogiston' when burned. He explained how combustion, animal respiration and rusting all required oxygen. In the preface to his textbook, Lavoisier explains how it began as an attempt to reform chemical nomenclature. The fact that it would become such a fundamental work apparently happened by accident: "My work transformed itself by degrees, without my being able to prevent it, into a treatise upon the Elements of Chemistry," Lavoisier writes. Sadly for Lavoisier and for chemistry, he was executed during the French Revolution just five years after publishing his treatise.

"Principles of Chemistry" by Dmitri Mendeleev, 1868–1870 Remember learning the periodic table in high school chemistry? Russian chemist Dmitri Mendeleev created the first version of the table, and used it to predict properties of elements that had not yet been discovered. Mendeleev developed the periodic table while writing a two-volume textbook called "Principles of Chemistry," published between 1868 and 1870. Based on similar properties, he grouped all the 63 known elements into families, such as the halogens, the alkali metals and the alkaline earths. He arranged the elements horizontally by their atomic weights and vertically by these families to create the periodic table. Legend has it that Mendeleev, a fan of the card game Patience (a form of solitaire), wrote the names of elements on cards and arranged them into his periodic table. Mendeleev noticed holes in his table that suggested the existence of new elements. However, his work wasn't widely recognized until some of his predicted elements were discovered.