Where once there was a star 20 times the size of our sun, now there is a record breaker. Astronomers report this week in Nature that when the huge star went supernova, it collapsed into a neutron star that is heaviest they've ever seen, with twice the mass of our sun compacted into a tiny space. Aside from taking its place in the record books, this massive monster could reveal what truly goes on deep in the heart of a deceased star. The neutron star is part of a binary star system called J1614-2230, in which it and a white dwarf are locked in a spin cycle. Thanks to the neutron star's steady emission of radio waves and a handy trick of relativity, scientists can measure the size of the two objects despite the fact that they're 3,000 light years from here.
The astronomers took detailed measurements of the radio pulses that reached Earth. As these pulses, which originate from the rotation of the neutron star, passed by the companion white dwarf, their timing was delayed due to the highly warped nature of spacetime—an effect known as Shapiro delay. In a highly inclined, nearly edge-on system such as J1614-2230 the effect allows astronomers to make very accurate measurements both of the neutron star and its companion. [Ars Technica]