Idaho Skies Transcript for April 29th and 30th

PAUL
Welcome to Idaho Skies for April 29th and 30th. We’re your hosts, Paul...

RACHEL
...and Rachel.

PAUL
Did you know that you can visit a gravitational wave observatory in Washington?

RACHEL
Many Idaho Sky listeners have visited optical observatories, like the one at Bruneau Dunes. However, unlike an optical observatory, a gravitational wave observatory looks for and measures disturbances in the fabric space-time. So astronomers there aren’t looking through telescopes. 

PAUL
Since gravitational waves distort space and time, their passage causes the distance between objects to shift slightly. The amount of shift is smaller than the diameter of a proton once it reaches Earth. If you recall from school, protons are one of the subatomic particles inside the nucleus of an atom.

RACHEL
So how on Earth do you measure a gravitational wave on Earth? Well, out at the Hanford site in eastern Washington, MIT and CalTech have built a two-mile long interferometer. An interferometer is a device that compares two laser beams to each other. However, the beams have to come from the same laser to make this work.

PAUL
At the Laser Interferometer Gravitational Wave Observatory, the light of a single laser is split into two beams and send down two paths. When a gravitational wave passes through the observatory, the two paths vary in distance very slightly. And by using the process of interferometry, that tiny distance can be measured.    

RACHEL
That’s Idaho Skies for the 29th and 30th of April.

PAUL
Be sure to follow us on Twitter @IdahoSkies for this week’s event reminders and sky maps.
For Idaho Skies this is Paul...

RACHEL
...and Rachel.

PAUL
Dark skies and bright stars.