New Kind of Astrophysics is Born

  • By Ari Daniel
  • Posted 10.19.17
  • NOVA

An incredible discovery in astrophysics was unveiled today. Scientists saw and "heard" a dramatic cosmic explosion simultaneously for the first time.

Running Time: 02:00


Onscreen: For the first time, scientists saw AND "heard" a spectacular cosmic event. 130 million years ago, in a galaxy far, far away, a pair of neutron stars (the super dense, collapsed remains of ancient stars; one teaspoon weighs billions of tons) spiraled around each other, shredding each other and colliding, producing ripples in spacetime called gravitational waves and a bright explosion called a kilonova.

Two months ago, those gravitational waves washed across the Earth where LIGO in the US and Virgo in Italy detected them. Within minutes, a suite of telescopes (including here in Chile) searched for the accompanying kilonova in the sky and found it. 

Josh Frieman: We've never had this wealth of information about one kind of exotic explosion before.

Ryan Chornock: This is such a big deal because it's the birth of what we call multi-messenger astrophysics.

Onscreen: Here's why this matters. It's one of the best portraits yet of the final moments of neutron stars. Plus:

Jennifer Marshall: This is the very first time that astronomers were able to make an observation of two neutron stars merging.

Onscreen: It's also the strongest evidence so far that a neutron star collision can produce heavy elements, like platinum, uranium, and gold.

Frieman: This event produced about as much gold as the entire mass of the Earth.

Onscreen: Also, seeing and “hearing” means we can calculate the speed and distance of faraway objects with greater certainty. So with another couple dozen observations just like this one, scientists will have an independent estimate of the expansion rate of the universe.

We just have to keep watching and "listening."



Ari Daniel
Editorial Review
Julia Cort
Special Thanks
Edo Berger
Tim De Chant
Alyssa Goodman
Ivy Liu
Philip Rosenfield
© WGBH Educational Foundation 2017


Dark Energy Survey
Greg Kestin
The American Astronomical Society’s WorldWide Telescope
NASA, ESA, F. Summers, Z. Levay, L. Frattare, B. Mobasher, A. Koekemoer, HUDF Team (STScI)
Ryan Shepheard, Doug Quade, Edgeworx Studios
Chile Footage
Director of Photography: Dave Adams
Drone Operator: Cristian Muñoz Opazo
Sound: Rodrigo Salvatierra
Direction: Kirk Wolfinger


(main image: gravitational waves and neutron stars)

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