Ep. 377: Thomson finds Electron
At the end of the 19th century, physicists were finally beginning to understand the nature of matter itself, including the discovery of electrons – tiny particles of negative charge that surround the nucleus. Here’s how J.J. Thompson separated the electrons from their atoms and uncovered their nature.
Ep. 376: The Miller-Urey Experiment
Evolution explains how life adapts and evolves over eons. But how did life originate? Chemists Miller and Urey put the raw chemicals of life into a solution, applied an electric charge, and created amino acids – the building blocks of life.
Ep. 375: The Search For Life in the Solar System
With the discovery of water ice in so many locations in the Solar System, scientists are hopeful in the search for life on other worlds. Guest Morgan Rehnberg returns to Astronomy Cast to explain the best places we should be looking for life.
Ep. 374: Stern-Gerlach Experiment
In the world of quantum mechanics, particles behave in discreet ways. One breakthrough experiment was the Stern-Gerlach Experiment, performed in 1922. They passed silver atoms through a magnetic field and watched how the spin of the atoms caused the particles to deflect in a very specific way.
Ep. 373: Becquerel Experiment (Radiation)
Antoine Henri Becquerel discovered radioactivity completely by accident when he exposed a chunk of uranium to a photographic plate. This opened up a whole new field of research to uncover the source of the mysterious energy.
Ep. 372: The Millikan Oil Drop
In 1909 Robert Millikan devised an ingenious experiment to figure out the charge of an electron using a drop of oil. Let’s talk about this Nobel Prize winning experiment.
Ep. 371: Eddington Eclipse Experiment
At the turn of the 20th Century, Einstein’s theory of relativity stunned the physics world, but the experimental evidence needed to be found. And so, in 1919, another respected astronomer, Arthur Eddington, observed the deflection of stars by the gravity of the Sun during a solar eclipse. Here’s the story of that famous experiment.
Ep. 370: The Kaufmann–Bucherer–Neumann Experiments
One of the most amazing implications of Einstein’s relativity is the fact that the inertial mass of an object depends on its velocity. That sounds like a difficult thing to test, but that’s exactly what happened through a series of experiments performed by Kaufmann, Bucherer, Neumann and others.
Ep. 369: The Fizeau Experiment
Light is tricky stuff, and it took scientists hundreds of years to puzzle out what this stuff is. But they poked and prodded at it with many clever experiments to try to measure its speed, motion and interaction with the rest of the Universe. For example, the Fizeau Experiment, which ran light through moving water to see if that caused a difference.
Ep. 368: Searching for the Aether Wind: the Michelson–Morley Experiment
Waves move through a medium, like water or air. So it seemed logical to search for a medium that light waves move through. The Michelson-Morley Experiment attempted to search for this medium, known as the “luminiferous aether”. The experiment gave a negative result, and helped set the stage for the theory of General Relativity.