When the Royal Astronomical Society announced Shrinivas R. Kulkarni as the recipient of its Gold Medal, it marked more than another milestone in a decorated career. Awarded continuously since 1824, the medal is the Society’s highest honour, reserved for scientists whose work has fundamentally altered how humanity understands the universe.The prestigious award placed him among an elite group of scientific pioneers, Albert Einstein, Stephen Hawking, Edwin Hubble, and recognised his “field-defining” work in time-domain astronomy. Remarkably, Kulkarni is only the second Indian to receive the RAS Gold Medal, following Subrahmanyan Chandrasekhar, honoured in 1953 for his groundbreaking work on the structure and evolution of stars.In Kulkarni’s case, the citation acknowledged a lifetime spent reshaping astronomy itself, from a static science of distant objects into a dynamic discipline that tracks the universe in motion. Born in Maharashtra and educated in India before moving to the United States, Kulkarni’s career now spans more than four decades at the very frontier of astrophysics. The RAS credited him for “sustained, innovative and ground-breaking contributions to multi-wavelength transient astrophysics,” a field concerned with short-lived and rapidly evolving cosmic events. Few astronomers have done more to define that field, or to build the instruments that made it possible.
From India to the frontiers of astrophysics
Shrinivas Kulkarni was born in Kurundwad, a small town in Maharashtra, and spent his early years moving across Karnataka due to his father’s work as a government doctor. He completed his schooling in Hubli before enrolling at IIT Delhi, where he pursued an integrated BSc and MSc programme, graduating in 1978. From the outset, his ambition ran counter to expectation. “I wanted to do research and not go into industry or be a doctor or lawyer or engineer which is sort of the more traditional path,” he later recalled. That resolve took him to the United States, where he completed his PhD in astronomy at the University of California, Berkeley in 1983, specialising in radio astronomy. Of that period, he said: “I had an exceptional advisor who understood what I really wanted to do.” A Millikan Fellowship brought him to the California Institute of Technology, beginning an association that would define the rest of his professional life.Kulkarni joined Caltech’s faculty in 1987, progressing from assistant professor of astronomy to associate professor, professor, professor of astronomy and planetary science, MacArthur Professor, and eventually the George Ellery Hale Professor of Astronomy and Planetary Science. Along the way, he served as executive officer for astronomy and as director of Ca ltech Optical Observatories, overseeing the Palomar and Keck telescopes, two of the international astronomy community’s most prized instruments.
Discoveries that changed astronomy
Kulkarni’s scientific reputation rests not on a single breakthrough, but on a sequence of discoveries that repeatedly shifted the field’s centre of gravity. As a graduate student in 1982, he co-discovered the first millisecond pulsar, a neutron star rotating hundreds of times per second, forcing astronomers to rethink how stellar remnants evolve. In 1995, he and his colleagues identified the first brown dwarf, an object too large to be a planet yet too small to sustain hydrogen fusion like a star, opening an entirely new category of celestial bodies. Two years later, Kulkarni was part of the team that measured the distance to a gamma-ray burst for the first time, demonstrating that these violent flashes originated billions of light-years away, far beyond the Milky Way. More recently, his work has helped unravel the mystery of fast radio bursts (FRBs). Using an instrument known as STARE2, developed earlier in his career with a graduate student, Kulkarni was part of the team that in 2020 detected an FRB originating within the Milky Way itself. The source, a magnetar, or highly magnetised neutron star, provided the first direct confirmation that such objects can generate FRBs.
Building the machines that watch the sky
Equally central to Kulkarni’s legacy is his insistence that discovery depends on instrumentation. “My motto has been to build a big enough gizmo and things will happen,” he said in one of his Caltech lectures. Over his career, he has helped construct around ten astronomical instruments, many designed to capture fleeting cosmic events that older observatories would miss. This philosophy culminated in the Palomar Transient Factory (PTF) in 2009 and its successor, the Zwicky Transient Facility (ZTF) in 2017. Using a 70-year-old telescope at Palomar Observatory, these surveys scan the entire northern sky every two nights. Automated software analyses the data, and alerts about transient events, supernovae, asteroids, flaring stars, are sent to astronomers worldwide within minutes. According to the award citation, these projects have “revolutionised time-domain astrophysics at optical wavelengths.” The data from PTF and ZTF has enabled discoveries ranging from a star swallowing one of its planets, to some of the closest and brightest supernovae ever recorded, to binary stars orbiting each other every seven minutes and emitting low-frequency gravitational radiation. Funded by institutions worldwide and supported by major grants from the National Science Foundation and the Heising-Simons Foundation, the projects have also trained a new generation of astronomers now leading the field. Reflecting on ZTF after winning the Shaw Prize, Kulkarni remarked: “ZTF is only possible at Caltech, which values exceptionalism.”
Family, curiosity, and a lifelong fascination with the cosmos
Behind the accolades is a life shaped by an unusually high-achieving family, one that helps explain both Kulkarni’s intellectual confidence and his sensitivity to hierarchy. He is the youngest of four siblings and the brother of author, educator and philanthropist Sudha Murty, who is married to Infosys founder and billionaire Narayana Murthy. His eldest sister, Sunanda, followed their father into medicine and served as a gynaecologist at a government hospital in Bengaluru. Another sister, Jayshree, an IIT Madras alumna, is married to Boston-based IT entrepreneur Gururaj “Desh” Deshpande, one of the wealthiest Indian-born entrepreneurs and a billionaire. “All my sisters were gold medallists and evolved into competent professionals,” Kulkarni said in an interview. “Coming from such a family, I found it strange that there were so few women in high places in the US when I first moved to that country.”
Shrinivas Kulkarni in an old family picture with his parents and sisters Jayashree, Sudha and Sunanda | Photo Credit: rediff.com
During his PhD years at the University of California, Berkeley, Kulkarni met Hiromi Komiya, a doctoral student from Japan. He learned Japanese within a matter of weeks, and the two married soon after. They have two daughters, Anju and Maya.Although his work has helped define some of the most serious frontiers of modern astrophysics, Kulkarni has often pushed back against the popular image of scientists as permanently solemn or detached. In one interview with The Global Indian, he addressed that perception directly. “We astronomers are supposed to say, ‘We wonder about the stars and we really want to think about it,’” he said, acknowledging the stereotype. But, he added, that image misses something essential. “Many scientists, I think, secretly are what I call ‘boys with toys.’ I really like playing around with telescopes. It’s just not fashionable to admit it.”That combination, deep technical seriousness paired with a visible delight in experimentation, has remained a through-line in Kulkarni’s career, shaping both his discoveries and his lifelong commitment to building the tools that allow the universe to surprise us.
Recognition earned over a lifetime
The RAS Gold Medal joins a formidable list of honours, including the 2024 Shaw Prize in Astronomy, the US National Science Foundation’s Alan T. Waterman Award, the Dan David Prize, the Jansky Prize, and the Helen B. Warner Award. He is a member of the US National Academy of Sciences, the Royal Society of London, and the Indian Academy of Sciences. Kulkarni continues to work on future projects, including NASA’s Ultraviolet Explorer (UVEX), planned for launch around 2030, and Z-Shooter, a next-generation spectrometer for the Keck Observatory. Reflecting on awards, he has said simply: “Awards open doors.” With the Royal Astronomical Society’s Gold Medal, Shri Kulkarni takes his place among scientists whose work has not only explained the universe, but transformed how we observe it, teaching astronomy to watch the sky not as a fixed backdrop, but as a living, changing system.
