The Vela pulsar wind nebula. Light blue represents X-ray polarisation data from the NASA Imaging X-ray Polarimetry Explorer. Pink and purple colours correspond to data from the NASA Chandra X-Ray observatory.
| Photo Credit: NASA
Indian astronomers, including from IIT-Kanpur, have developed a new way to measure distances in the universe using the pulsating cores of dead stars, by studying how their radio emissions are distorted as they travel through space. The technique combines a pair of subtle effects that occur when pulsar signals pass through clouds of ionised gas in the Milky Way.
The dense and rapidly spinning remnant cores of dead stars are called pulsars. They emit beams of radio waves that sweep across the earth like light from a lighthouse sweeps across ships at sea. Pulsars have an extraordinarily fixed spinning rate, so the pulses arrive very regularly. So astronomers have used them as cosmic clocks.
Published – April 09, 2026 07:30 am IST
