Astronomers have discovered a pulsar that is moving between 2.5 million and 5 million miles per hour with a tail that stretches for 37 light years behind the pulsar.
An extraordinary jet trailing behind a runaway pulsar is seen in this composite image that contains data from NASA’s Chandra X-ray Observatory (purple), radio data from the Australia Compact Telescope Array (green), and optical data from the 2MASS survey (red, green, and blue). The pulsar – a spinning neutron star – and its tail are found in the lower right of this image (mouse over the image for a labeled version). The tail stretches for 37 light-years, making it the longest jet ever seen from an object in the Milky Way galaxy.
The pulsar, originally discovered by ESA’s INTEGRAL satellite, is called IGR J1104-6103 and is moving away from the center of the supernova remnant where it was born at a speed between 2.5 million and 5 million miles (4 million and 9.7 million kilometers) per hour. This supersonic pace makes IGR J1104-6103 one of the fastest-moving pulsars ever observed.
Astronomers have found a remarkable object in our Milky Way galaxy. This object is a pulsar, the spinning dense core that remains after a massive star has exploded and collapsed. When this pulsar was created, something interesting happened because this pulsar is racing away from the supernova remnant where it was born at a speed between 2.5 million and 5 million miles per hour. This supersonic pace makes this pulsar – called IGR J1104-6103 — one of the fastest-moving pulsars ever observed. And what’s more, is that this runaway pulsar is leaving behind an extraordinary tail behind it as it goes. This tail is about 37 light years in length, making it the longest X-ray jet ever seen from an object in the Milky Way galaxy. New data from NASA’s Chandra X-ray Observatory have been combined with radio data from the Australia Telescope Compact Array to provide astronomers with a more complete picture of what’s happening in this system. For example, these data show that the tail has a distinct corkscrew shape. This suggests that the pulsar is wobbling like a top as it spins. IGR J1104-6103 is located about 60 light years away from the center of the supernova remnant SNR MSH 11-61A, which is where astronomers think the pulsar was originally created. By examining the details of the pulsar, its jet, and the supernova remnant, astronomers are piecing together the story of this exceptional object in our Galaxy. Credit: NASA/CXC/A. Hobart
A massive star ran out of fuel and collapsed to form the pulsar along with the supernova remnant, the debris field seen as the large purple structure in the upper left of the image. The supernova remnant (known as SNR MSH 11-61A) is elongated along the top-right to bottom-left direction, roughly in line with the tail’s direction. These features and the high speed of the pulsar suggest that jets could have played an important role in the supernova explosion that formed IGR J1104-6103.
In addition to its exceptional length, the tail behind IGR J1104-6103 has other interesting characteristics. For example, there is a distinct corkscrew pattern in the jet. This pattern suggests that the pulsar is wobbling like a top as it spins, while shooting off the jet of particles.
Another interesting feature of this image is a structure called a pulsar wind nebula (PWN), a cocoon of high-energy particles that enshrouds the pulsar and produces a comet-like tail behind it. Astronomers had seen the PWN in previous observations, but the new Chandra and ATCA data show that the PWN is almost perpendicular to the direction of the jet. This is intriguing because usually the pulsar’s direction of motion, its jet, and its PWN are aligned with one another.
One possibility requires an extremely fast rotation speed for the iron core of the star that exploded as the supernova. A problem with this scenario is that such fast speeds are not commonly expected to be achievable.
Nothing in space stays still. In fact, most stars are like long-distance marathon runners, as they are constantly moving in space throughout their lifetimes. However, astronomers have recently spotted a star (shown in this new space photo as a green smudge in the box) that is better at sprint running.
To work out the speed of this star, astronomers had to figure out how far it has traveled since it started its race and how long this took. Astronomers think the star began its race at the center of the purple cloud of gas and dust in the photo. That’s because this is a special type of star that rotates very quickly, which is called a pulsar. And the pulsar was ejected during the explosion that created the cloud of gas and dust.
Based on their estimates, the astronomers think the pulsar is moving at an incredible speed of between 5 million and 7 million miles per hour! This could make it the fastest moving pulsar ever known! But there is a competitor for the title, as another pulsar has previously been estimated to be moving between 3 and 6 million miles per hour.
It’s a pity astronomers can’t enter these two stars into a ‘Space Olympics’ to determine which one is the fastest sprinter. Instead, they need to work it out the hard way and fine-tune their results.
Credit: NASA/CXC/April Jubett
A paper, led by Lucia Pavan of the University of Geneva in Switzerland, describing these results appears in the February 18th issue of the journal Astronomy & Astrophysics and is also available online. Other authors include Pol Bordas (University of Tuebingen in Germany), Gerd Puehlhofer (Univ. of Tuebingen), Miroslav Filipovic (University of Western Sydney in Australia), A. De Horta (Univ. of Western Sydney), A. O’Brien (Univ. of Western Sydney), M. Balbo (Univ. of Geneva), R. Walter (Univ. of Geneva), E. Bozzo (Univ. of Geneva), C. Ferrigno (Univ. of Geneva), E. Crawford (Univ. of Western Sydney), and L. Stella (INAF).
Reference: “The long helical jet of the Lighthouse nebula, IGR J11014-6103” by L. Pavan, P. Bordas, G. Puehlhofer, M. D. Filipovic, A. De Horta, A. O’Brien, M. Balbo, R. Walter, E. Bozzo, C. Ferrigno, E. Crawford and L. Stella, 18 February 2014, Astronomy & Astrophysics.