'One of those rare 'wow' moments': Zombie star near Earth has a rainbow shockwave that 'shouldn't be there'

Astronomers discovered a white dwarf star 730 light-years from Earth that's creating an impossible rainbow shock wave as it devours its companion star. The zombie star RXJ0528+2838 shouldn't produce such outflows according to current understanding, leaving researchers baffled about the "mystery engine" behind this spectacular 4,000-Earth-sun-distance nebula.