This is a continuation of the Science Cats! theme I started last month. If you enjoy these, feel free to share them with friends and family, and make suggestions or requests in the comments.
Illustration of the classic Rutherford scattering experiment in which alpha particles (helium nuclei) elastically scatter from the nuclei of gold atoms (elastic scattering means the lighter α particles bounce off of the heavy Au atoms like billiard balls without losing their speed). In 1911, Ernest Rutherford used this experiment to prove that most of the mass of an atom is tightly concentrated in a tiny core nucleus in the atom, falsifying the previous "plum pudding model" of the atom in which the electrons are dispersed throughout a smeared-out positive spherical volume like blueberries in a muffin. The Rutherford Model for the atom was later updated in 1913 by the Bohr Model, which begins to hint at the first quantum mechanical picture of the atom. In this incarnation of the Rutherford scattering experiment, Chloe serves as the source of α particles.
Polish astronomer and mathematician Nicolaus Copernicus formulated and published the heliocentric model in the first half of the 16th century, forever changing how humanity viewed its relationship to the Cosmos. The awe and majesty of this newly expanded cosmic perspective was beautifully captured in this 1873 oil painting by artist Jan Matejko (also Polish). In the foreground of the painting, Chloe plays with a rope and a random wooden pulley thing, completely oblivious to beauty and grandeur of the rest of the universe.
"Professor Goddard does not know the relation between action and reaction and the need to have something better than a vacuum against which to react. He seems to lack the basic knowledge ladled out daily in high schools." -New York Times editorial from January 13, 1920, which was famously retracted in 1969 after the Apollo moon landing. Robert Goddard was ridiculed by the unimaginative fools in the press throughout his career and as a result kept much of his groundbreaking work private. His liquid-fueled multistage rockets were major milestones in the development of rocketry and the advance of space exploration.
If you liked these, be sure to check out Science Cats Volume 1!