No, it's not Rosie.

It's a big fat pulsar:

The astronomers think the pulsar may once have been part of a triple system of stars and was ’spun-up‘ by its closest companion star – which was either ejected from the system or worn away after it transferred all its mass to the pulsar – and now remains in an elongated orbit around the third, more distant member of the original trio.

Oh yeah, this article is kinda dirty too because it talks about the sex life of stars.