November 22 2014 Astronomy Newsletter
Here's the latest article from the Astronomy site at BellaOnline.com.
Cancer the Crab
Cancer the crab scuttles across the late winter sky, well away from its nemesis Hercules. Cancer is a zodiac constellation, the Tropic of Cancer is named for it, and it has existed for over three thousand years. Yet it seems to be a dim and unremarkable constellation. Why all the attention?
*Edwin Hubble – 125 years*
One of the best known names in astronomy, Edwin Hubble, was born on November 20, 1889. Henrietta Leavitt had found a relationship between the luminosity and the period of variation in a certain class of variable stars. This discovery paved the way for using these stars to calculate distances. Hubble found such a variable star in what was then known as the Andromeda nebula. He was able to establish that it was *not* an object in our own galaxy. This pretty well settled the debate about whether there were galaxies beyond our own. Here is a copy of the pivotal image: http://www.pinterest.com/pin/250090585531415562/
Hubble then went on to use red shift measurements to show that most of the galaxies we could see were moving away from us. The more distant they were, the faster they seemed to be receding. This was the Hubble Law. Cosmologists recognized it as evidence for an expanding universe.
And, of course, the wonderful Hubble Space Telescope has carried Hubble's name to many people who don't know of the pivotal work he did.
If you haven't yet heard the music Vangelis (“Chariots of Fire”) wrote for the Rosetta mission, do have a look. (I really like “Rosetta's Waltz”.) You can find them on my board "Astronomy and Music" http://www.pinterest.com/astrobella/astronomy-and-music/ I guess if William Herschel were around, he might also have written something for Rosetta!
Here's something beautiful to lift you up today. “Wavelight” is a remarkable timelapse made from 10,000 stills taken at the Wave formation in Arizona. The sky and the formation are individually exquisite, but when combined so that you get star trails with the waves in the sandstone, it's stunning. http://www.pinterest.com/pin/250090585533516977/
Please visit astronomy.bellaonline.com for even more great content about Astronomy.
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I wish you clear skies.
Mona Evans, Astronomy Editor
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