The LIGO detector in Louisiana. Photo: Caltech/MIT/LIGO Lab

Astronomers think they've detected the ripples in space and time sent out by a black hole and neutron star colliding.

The big picture: Scientists have detected gravitational waves sent out by 2 black holes merging and 2 neutron stars merging, but if confirmed, this will be the first detection of a black hole and neutron star colliding.

Why it matters: Astronomers hope that the Aug. 14 detection will help them learn more about both black holes and neutron stars, the super dense remnants of dead stars.

Details: Researchers aren't yet sure of the exact size of the black hole or neutron star that sent out the gravitational waves, but further analysis could help determine the masses of the two objects.

  • "[W]e're very confident that we've just detected a black hole gobbling up a neutron star," physicist Susan Scott, of Australian National University, said in a statement.
  • “However, there is the slight but intriguing possibility that the swallowed object was a very light black hole — much lighter than any other black hole we know about in the universe. That would be a truly awesome consolation prize.”

How it works: The two LIGO detectors in Washington state and Louisiana and the Virgo detector in Italy are responsible for listening for gravitational waves emitted by cosmic crashes as they move through our part of space.

  • The sensitive L-shaped observatories use lasers to pick up the moment that the ripples pass through Earth, slightly warping everything they pass through as they go.

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Editor's note: This article has been updated with the latest coronavirus case numbers and more context.