AstroSat, India’s first multi-wavelength space-based observatory, has detected bright sub-second X-ray bursts from a unique neutron star with ultrahigh magnetic field (magnetar). These bursts, lasting for milli-seconds, provide insights into the extreme astrophysical conditions of magnetars. The magnetar, known as SGR J1830-0645, was discovered by NASA’s Swift spacecraft and studied by scientists from Raman Research Institute and University of Delhi using AstroSat's instruments. The study revealed the presence of emission lines in the spectra of the magnetar, contributing to our understanding of magnetars and their extreme conditions.