Astronomy Cast Ep. 371: The 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.
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Astronomy Cast 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.
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Astronomy Cast 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.
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Astronomy Cast 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.
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Astronomy Cast Ep. 367: Spitzer does Exoplanets

We’ve spent the last few weeks talking about different ways astronomers are searching for exoplanets. But now we reach the most exciting part of this story: actually imaging these planets directly. Today we’re going to talk about the work NASA’s Spitzer Space Telescope has done viewing the atmospheres of distant planets.
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