TIFR Finds Way To Measure Neutron Stars

After Chandrayaan’s discovery of water molecules on the moon comes another astronomy breakthrough for India. An international group led by Sudip Bhattacharyya, a 36-year-old space scientist at Mumbai’s Tata Institute of Fundamental research (TIFR), has discovered a way to measure the size of neutron stars. Before we go any further, what is a neutron star? Bhattacharyya explained: “To put it simply, it is the final stage of a very massive star. When the massive star burns up its fuel, it collapses to become a neutron star.” He added there are between 100 million and 1,000 million neutron stars in the galaxy. A neutron star is usually very small — approximately 10 km in diameter — and 10,000 light years from Earth, thus making it extremely difficult to study and measure. Bhattacharyya and his team’s research revealed the unsuspected property of X-ray bursts emitted by the stars, which led to the theory that the pattern of X-rays generated might reveal their true size. “Since these X-rays could not reach Earth because of a blanket created by the atmosphere, data was collected of more than 900 bursts from 43 neutron stars through a Nasa satellite and transmitted to us,” Bhattacharyya said. The scientist and his colleagues — Coleman Miller of the University of Maryland, US, and Galloway Monash of the University of Australia — modelled how the temperature of the bursts changed as they faded. They found it varied in relation to the radius of the star. The team’s research will be published in Monthly Notices, a journal of the Royal Astronomical Society. “We feel it will have far-reaching implications in areas like physics, astrophysics and also in the field of nuclear reaction,” said Bhattacharyya, who won a Nasa achievement award in 2007.