Indian American professor Shrinivas R. Kulkarni has been honored with the 2024 Shaw Prize in Astronomy for his significant contributions to the study of millisecond pulsars, gamma-ray bursts, supernovae, and other variable or transient astronomical phenomena.
Kulkarni, who holds the George Ellery Hale Professorship of Astronomy and Planetary Science at the California Institute of Technology, was recognized alongside three other laureates by the Shaw Prize Foundation in Hong Kong on May 21.
The astronomy selection committee commended Kulkarni for his leadership in time-domain astronomy, particularly through the creation and management of the Palomar Transient Factory and the Zwicky Transient Facility. These initiatives have profoundly advanced our understanding of the dynamic optical sky.
Stars typically shine steadily for billions of years, but some exhibit variations, pulsations, flares, or explosions over much shorter timescales. These rapid changes offer unique insights into stellar death, matter behavior under extreme conditions, the universe’s size and age, and fundamental physics topics like the nuclear equation of state and Einstein’s theory of general relativity.
The committee highlighted the challenges of time-domain astronomy, which involves analyzing vast datasets to identify rare anomalies, eliminating false positives, and promptly informing the astronomy community to facilitate further observations.
Throughout his career, Kulkarni has made numerous groundbreaking discoveries in optical and radio astronomy. As a student, he and his colleagues discovered the first millisecond pulsar, a neutron star emitting precisely timed pulses over 600 times per second. Today, hundreds of such pulsars are known and used to test Einstein’s theory of relativity and search for gravitational waves.
Kulkarni’s research has also demystified gamma-ray bursts, first detected in the 1960s. In 1997, he and his team determined that these bursts originate in the distant universe, revealing their extraordinary energy. More recently, he contributed to understanding fast radio bursts (FRBs), linking them to magnetars by building the STARE2 array, which detected an FRB from a magnetar within our galaxy in 2020.
Kulkarni’s initiatives, the Palomar Transient Factory (PTF) and its successor, the Zwicky Transient Facility (ZTF), utilize a historic telescope at Palomar Observatory to survey the Northern sky bi-daily, process data with automated software, and alert astronomers worldwide about transient events.
These surveys have led to the discovery of numerous astronomical phenomena, including supernovae, luminous red novae, calcium-rich gap transients, and star disruptions by black holes. They have also uncovered a star engulfing a planet, bright supernovae, a new class of asteroids, and binary stars emitting low-frequency gravitational waves, among other rare events.
The Shaw Prize also acknowledges Kulkarni’s contributions to stellar astronomy, notably his role in discovering one of the first brown dwarfs, bridging the gap between giant planets and hydrogen-burning stars. This discovery has paved the way for ongoing research into the atmospheres of sub-stellar objects.
