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Recordeddatescience

A neutron-star merger is detected in gravitational waves and light

The LIGO and Virgo detectors recorded the inspiral of two neutron stars; about eleven hours later an optical counterpart, AT2017gfo, was found in the galaxy NGC 4993 at roughly 40 megaparsecs. The transient faded and reddened over days in the manner predicted for material heated by the radioactive decay of freshly made r-process nuclei, with inferred ejecta of a few hundredths of a solar mass. It established neutron-star mergers as a site of heavy-element synthesis and is the founding event of multi-messenger astronomy.

Observed — measured or witnessed, with the observation cited.

Subjects

Evidence

Partly verified — Core facts are sourced; some optional detail is deliberately absent.

Recorded on Kilonova

  1. Baade and Zwicky propose supernovae and neutron stars
  2. B2FH sets out the synthesis of the elements in stars
  3. A regularly pulsing radio source is identified
  4. A pulsar is found inside the Crab Nebula
  5. SN 1987A: neutrinos from a collapsing core reach Earth
  6. A neutron-star merger is detected in gravitational waves and light
  7. A radius is measured for the heaviest known neutron star
  8. JWST finds the compact object in SN 1987A

Related

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