On August 17, 2017, an alert went out.

Gravitational wave detectors in Louisiana and Washington state had detected a disturbance from deep space.

The effect was subtle — these detectors and a sister site in Italy measure disturbances smaller than a proton. But the evidence was dramatic. And the story they told was truly cataclysmic:

A pair of neutron stars had spiraled to their deaths.

That apocalyptic collision of two super-dense stars bent the very fabric of space time — just as Einstein had predicted. It sent Gamma rays out into deep space. It created an immense cloud of gaseous gold.

And, 130 million years later, astronomers on earth witnessed the final 100 seconds of these two stars’ dance of death. It’s taught us where gold came from, and helped humans understand other intractable mysteries of the universe.

In this episode of Orbital Path, Dr. Michelle Thaller speaks with two astronomers who watched this cosmic death tango from the best seats in the house.

We’ll hear from Dr. Vicky Kalogera. She’s Director of CIERA — the Center of Interdisciplinary Exploration and Research in Astrophysics at Northwestern University. Kalogera was a lead author on a journal article on the neutron star collision co-authored by close to 4,000 scientists.

We’ll also hear from physicist Mike Landry. He’s Head of LIGO Hanford — one of the sites that, in collaboration with Italy’s VIRGO detector, measured the neutron stars’ characteristic gravitational waves.





Orbital Path is produced by David Schulman. The program is edited by Andrea Mustain. Production oversight by John Barth and Genevieve Sponsler. Hosted by Dr. Michelle Thaller.

Support for Orbital Path is provided by the Alfred P. Sloan Foundation, enhancing public understanding of science, technology, and economic performance. More at sloan.org

Image credit: CALTECH/NSF/LIGO Sonoma State University/A. Simonnet


Neutron star audio chirp credit: LIGO/University of Oregon/Ben Farr