Gravitational waves generated by a black hole and a companion body rapidly orbiting each other may not be as easy to detect as researchers had anticipated (SN: 1/8/00, p. 26: Available to subscribers at Catch a Wave). A new mathematical analysis suggests that as these spinning, compact bodies spiral in toward each other, their orbits become chaotic for certain configurations. It becomes extraordinarily difficult to predict details of their motion during the merger and, hence, crucial characteristics of the gravitational waves they would generate.
"As a result, the spinning pair will have unpredictable gravitational waveforms during coalescence," astrophysicist Janna Levin of the University of Cambridge in England remarks in the April 17 Physical Review Letters. "This poses a challenge to future [gravitational] wave observatories which rely on a match between the data and a theoretical template."