The spinning dead star and the companion star that it closely orbits were first discovered in 2007. Once the pulsar began siphoning off material from the companion star, its characteristic pulsing beam disappeared. Instead, the pulsar entered a constant, alternating cycle of operating in what astronomers call “high” mode and “low” mode. They discovered that an exchange of matter between the pulsar and its companion star triggers the unusual behavior of the pulsar. As the pulsar tugs at its companion star, gas releases from the companion and forms a disk around the pulsar before slowly falling toward it.

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Persons: ”, Maria Cristina Baglio, Francesco Coti Zelati, Coti Zelati, Sergio Campana Organizations: CNN, Astrophysics, New York University, Italian National Institute for Astrophysics, Institute of Space Sciences, Astronomers, Southern, Italian National Institute for Astrophysics ’, Observatory Locations: New York University Abu Dhabi, Barcelona, Spain, Chile