What's That Chirp Noise I Hear?

Posted on February 25, 2016 by Lesley Arnold

images-3I heard birds chirping outside my office window this morning and I acknowledged to myself what a sweet sound it is. Their twittering reminded me that as the Earth rotates, each of us hears the morning calls of birds. I thought of my students in far off places such as Australia, Costa Rica, and Italy and registered that they were hearing their birds at very different times than each other.
I like to sit back and dwell on the planet as a little spaceship floating in the universe. Here we all are, floating through space together, caught in an orbit of gravitational pull by our sun. I marvel at that! At the same time, I’m also in awe of the scientists that came before me with their observations and predictions about the Earth and the universe. It is because of them that I can even have these thoughts. My studies of their work has led me to know the universe. If you are in the middle grades of Oak Meadow , then you will study the concepts of meteorology and astronomy in 6th grade, to light and sound waves in 8th grade physics, that will serve as a foundation for your own viewing the universe.images-2
One exceptional and admirable scientist you will study about is Albert Einstein. His observations, predictions, and construction of theories continue to amaze us today. Just this month, one of his predictions made over 100 years ago was validated. Einstein predicted the existence of gravitational waves. Physicists at The Laser Interferometer Gravitational-Wave Observatory (LIGO) located in Hanford, Washington, and Livingston, Louisiana have been busy for about twenty five years hoping to detect the sound of gravitational waves.

Then, on September 14, 2015, at just before eleven in the morning, Central European Time, the waves reached Earth. Marco Drago, a thirty-two-year-old Italian postdoctoral student and a member of the LIGO Scientific Collaboration, was the first person to notice them. He was sitting in front of his computer at the Albert Einstein Institute, in Hannover, Germany, viewing the LIGO data remotely. The waves appeared on his screen as a compressed squiggle, but the most exquisite ears in the universe, attuned to vibrations of less than a trillionth of an inch, would have heard what astronomers call a chirp—a faint whooping from low to high. http://www.newyorker.com/tech/elements/gravitational-waves-exist-heres-how-scientists-finally-found-them

So the other “chirp” I am hearing isn’t the sound of birds! It’s the sound of gravitational waves!
To learn more about this, and to hear the chirp, go to http://www.sciencemag.org/news/2016/02/gravitational-waves-einstein-s-ripples-spacetime-spotted-first-time

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