A Tour of PSR B1259-63

Narrator (April Hobart, CXC): A fast-moving pulsar appears to have punched a hole in a disk of gas around its companion star and launched a fragment of the disk outward at a speed of about 4 million miles per hour. NASA’s Chandra X-ray Observatory is tracking this cosmic clump, which appears to be picking up speed as it moves out. The double star system, known as B1259 for short, contains a star about 30 times as massive as the Sun and a pulsar, which is an ultra-dense spinning neutron star.

The pulsar moves in a highly elliptical orbit around its companion star once every 41 months. The combination of rapid rotation and intense magnetic field of the pulsar has generated a strong wind of high-energy particles moving away from the pulsar at near the speed of light.  The massive companion star, meanwhile, is rotating so fast that it is close to breaking apart and this is spinning off a disk of material around the star. As the pulsar makes its closest approach to the star, it passes through this disk.

Astronomers used Chandra to observe B1259 three separate times between December 2011 and February 2014 and saw something rather unusual. The bright source in the center of these images is the binary system, while the smaller point-like source to the lower right seen in the second two observations is the clump that has been dislodged. The researchers determined that this cosmic clump is big – spanning 100 times the size of the Solar System. The Chandra observations also suggest that the clump is not only moving quickly, but may, in fact, be picking up speed. The acceleration could be due to the intense winds flowing off of the pulsar’s surface. Chandra will continue monitoring B1259 and its moving clump with observations scheduled for later this year and in 2016.