Compact radio emission indicates a structured jet was produced by a binary neutron star merger

Understand

The binary neutron star merger event GW170817 was detected through both electromagnetic radiation and gravitational waves.

• Its afterglow emission may have been produced by either a narrow relativistic jet or an isotropic outflow.
• High spatial resolution measurements of the source size and displacement can discriminate between these scenarios.
• We present Very Long Baseline Interferometry observations, performed 207.4 days after the merger, using a global network of 32 radio telescopes.