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Astronomycast, episode 368, searching for the Etherwind, the Mikkelsen Morley experiment.

Welcome to Astronomycast, our weekly facts based journey through the cosmos where we help you understand not only what we know, but how we know what we know.

My name is Fraser Cain, I'm the publisher of the universe today, and with me is Dr. Pamela Gay, a professor at Southern Illinois University, Edwardsville, and the Dr. Dredd, your cosmocrest. Hey Pamela, how you doing?

I'm doing well, how are you doing Fraser?

I am good, but I have some sad news to report, which I don't know if you heard this Tammy Plotner, who was one of the longest time writers for Universe Today, passed away last week.

Oh no.

A long struggle with MS, and so for Tammy joined Universe Today back in 2004, and she was really the first freelance writer that I ever hired, and she just did hundreds, thousands of articles over the course of her.

Of her work with me, including a fantastic series on the Messier objects, all the constellations, and did, which she was trying to turn into books.

And she did a, what's up, 2006, what to see in the Nights Guy every night, from 2006, then again, from 2007.

So she's just really infectious, amateur astronomer, taught me a ton of stuff, and it sucks that she passed away, and so she went offline for periods of time, and then we just heard from her local Astronomical Society that she passed away.

So I just want to thank Tammy for all the work that she did for both astronomy and for us personally at Universe Today. She's really going to be missed.

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So waves move through a medium like water or air. So it seems logical to search for a medium that light waves move through.

The Mikkelson-Morley Experiment attempted to search for this medium known as the Lou Maniferas Ether.

The experiment gave a negative result and helps set the stage for the theory of general relativity.

So we are going to be starting a new series, not sure how long this will last, where we are going to talk about pivotal experiments in space and astronomy that really helped change the way we look at the Universe.

And this is one of the biggies. So set the stage.

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