♪♪ geoff: Let's expand our horizons a bit wider and look at important findings that are literally about space, time and the cosmos as we know it. You might remember Albert Einstein theorized that as heavy objects move through space and time, they create ripple effects in the fabric of our universe. Now, an international team of scientists have detected new evidence of that. Researchers found new signs of gravitational waves -- waves that are affected by huge movements such as the collision of black holes. These are no small matters. Our science correspondent, miles o'brien, is here to break it down. What are gravitational waves? >> They are ripples in the fabric of time and Einstein predicted them in 1915 and they were verified by a ground-based observatory in 2015. What this latest discovery does is prove they are more ubiquitous and found at longer wavelengths. We are talking about a project funded by the national science foundation. They have been working on this for 15 years. It is worth spending a couple moments trying to understand gravitational waves. Jeffrey at Oregon state university gave me a little lesson we can sink our teeth into. >> One way to think about it is if you think about space-time as being jello, you have this, it's a little bit more firm than a regular jello, but you have jello and the space in between the sides of the jello gets jiggled by these really massive objects. And so you can imagine, you know, smack it in one side of a big giant cube of jello and a wave would pass through that cube of jello. And so things would compress and expand as that perturbation moves through the chunk of jello. Geoff: Help us understand the scientific significance. >> The laser beam observatory from 2015 was like galileo pointing his telescope at Jupiter. Now we are talking about much more complicated and larger telescopes, if you will, looking at other wavelengths. In this case a wavelength that could be one light year long and scientists have hypothesized that gravitational waves would have a background hum of them but it was impossible to be detected with any ground-based observatory to see these ripples at that magnitude. Geoff: I am still -- I am struck by the chaotic nature -- quixotic nature of the endeavor. How did the scientists do the work? >> Imagine an observatory half the size of our galaxy. They took advantage of pulsars, which are dead stars that are very dense on the size of our city. They used pulsars, dead stars, which have predictable rotating begins and you can really set your clock to it. And if there is any change in them you can infer something is happening, in this case a great educational -- a gravitational waves that is changing. So they were able to pick up subtle changes and identify where they infer to be these gravitational waves. Geoff: Do scientists know what caused the ripples in the gravity? >> They think it might be super massive black holes. Space is a rough place and the idea is they are taking out these gravitational waves but now I am officially getting in deep for a history major so let's go back to Jeff at Oregon state university for his best current hypothesis. >> It's most likely from an ensemble of millions of black hole binaries, supermassive gargantuan sized black holes that live at the centers of galaxies. When two of them settle in after a galaxy merger, that's when they give off the gravitational waves that we're looking for. But we aren't there yet. Geoff: So what is next? What questions do the scientists hope to answer? >> They want to hone in on individuals and help connect the dots between these bouncing around massive black holes and long gravitational waves and in so doing, create a cosmic archaeology, understand more about how the universe formed and where it is going and doing that by listening to the home of the universe. -- Hum of the universe. Geoff: Miles o'brien, I always
