Explosions from dead stars unveil universe's expansion rate

Scientists propose using the collision and merger of neutron stars, known as kilonovas, as a third method to determine the Hubble constant and resolve the discrepancy between supernova and cosmic microwave background measurements. The symmetrical and spherical nature of kilonovas allows for precise calculations of their luminosity, which can be used to determine the distance to galaxies hosting these explosions. This method bypasses uncertainties associated with supernova measurements and provides a "clean" system to study cosmic distances, although more examples are needed to establish a robust result.