Shri Kulkarni, the George Ellery Hale Professor of Astronomy and Planetary Science, has been awarded the Gold Medal of the Royal Astronomical Society, the highest honor from the organization, awarded annually since 1824.
According to the award citation, Kulkarni is receiving the award for his "sustained, innovative and ground-breaking contributions to multi-wavelength transient astrophysics."
In 1982, while still a graduate student, Kulkarni discovered the first millisecond pulsar, a rapidly rotating neutron star. Since joining Caltech in 1985, Kulkarni has discovered a wide range of astronomical objects, including brown dwarfs, remote bursts of gamma rays, and more. In 1995, he and his colleagues discovered the first brown dwarf—a cooler, smaller cousin to stars. Other landmark findings include demonstrating in 1997 that powerful gamma-ray bursts originate outside our galaxy, and, in 2020, helping to catch the first fast radio burst, or FRB, to erupt in our own Milky Way galaxy, a finding that showed these exotic flares may come from magnetized dead stars called magnetars.
Kulkarni also led the development of the Palomar Transient Factory (PTF) and its successor, the Zwicky Transient Facility (ZTF), which have caught thousands of real-time cosmic events as they blink, explode, and otherwise light up the skies. ZTF, based at Caltech's Palomar Observatory near San Diego, is still going strong today, surveying the entire Northern sky every two nights. The two projects, his award citation notes, "have revolutionised time domain astrophysics at optical wavelengths."
In his 2024 Watson Lecture at Caltech titled "Illuminating the Dynamic Night Sky: Discoveries from the Zwicky Transient Facility," Kulkarni discussed his passion for building instruments to explore uncharted areas in astronomy. He has built a total of 10 instruments in his career. "My motto has been to build a big enough gizmo and things will happen," he said.
Currently, Kulkarni is involved with developing NASA's UVEX (Ultraviolet Explorer) mission, led by Fiona Harrison, the Harold A. Rosen Professor of Physics at Caltech. The mission, targeted to launch in 2030, will perform the most sensitive sky survey in ultraviolet light to date. He is the principal investigator of Z-Shooter, a very powerful and versatile spectrometer for the W. M. Keck Observatory in Hawai'i that is under development. First light is expected in 2029.
Kulkarni was born in Maharashtra, India. He received his master's degree from the Indian Institute of Technology Delhi in 1978 and his PhD from UC Berkeley in 1983. He arrived at Caltech on a Millikan Fellowship in 1985 and joined the faculty in 1987. He became the George Ellery Hale Professor of Astronomy and Planetary Science in 2017. He was also executive officer for astronomy (1997–2000) and director of Caltech Optical Observatories (2006–18), a position that includes overseeing Palomar and Caltech's joint role with other partners in the W. M. Keck Observatory.
Kulkarni has received numerous awards including the Shaw Prize, the National Science Foundation's Alan T. Waterman Award, and the Dan David Prize, awarded by Tel Aviv University. He is a member of the National Academy of Sciences, the Royal Society of London, the Indian Academy of Sciences, and the Royal Netherlands Academy of Arts and Sciences.