Rare black hole and neutron star collisions sighted twice in 10 days

In the first collision, which took place on 5 January 2020, a black hole six-and-a-half times the mass of our Sun crashed into a neutron star that was 1.5 times more massive than our parent star. In the second collision, just 10 days later, a black hole of 10 solar masses merged with a neutron star of 2 solar masses.