I was born in a small town in the erstwhile principality of Kurundwad, India and grew up in Hubballi, a provincial town in Northern Karnataka. In 1978 I graduated with a degree in Master of Physics (what would be called Engineering Physics in the US) from the Indian Institute of Technology, Delhi (IITD) and obtained a PhD in radio astronomy from UC Berkeley (UCB) in 1983. I continued as a post-doctoral fellow at UCB and joined Caltech in 1985 where I have been ever since. I served as Executive Officer for Astronomy (1997–2000) and as Director of the Caltech Optical Observatories (COO) from 2006 to 2018.
My father was a government doctor. I was the youngest of four siblings. We were a middle-class family with no ancestral or other wealth and, like many other families in this position, the way forward was through higher education. My parents made studying a priority for all of us.
In high school I was particularly influenced by Mr Shyamsundar (Mathematics) and Mr Satyanarayan Rao (Physics). I decided that I wanted to be a scientist instead of the prevalent choice of engineer. I self-studied for the Joint Entrance Exam in 1973. Separately, I also won a National Science Talent Search (NSTS) fellowship which came with a monthly stipend, a magnificent annual book allowance of INR 1,000 and a choice of an annual summer school.
The 1976 summer school on Astrophysics (Raman Research Institute) was eventful. Upon graduation, desiring to focus on experimental radio astronomy, I applied for a graduate program at UCB. By the end of my first year, I developed a vision for my thesis: learn all the techniques of radio astronomy so that I could investigate a broad range of astronomical phenomenology.
My career in astronomy has been guided by two dicta. First, I do not like to work in fields that are popular. Second, I like to see rapid progress. The resulting modus operandi is as follows: [1] Look widely and identify questions in fields which are interesting but not popular and where technological changes are likely to have a big impact. [2] Work in that field, make (ideally) a discovery and then [3] leave the field once it has become popular.
I joined Caltech as a Millikan post-doctoral fellow. I motivated and participated in the discovery of the first millisecond pulsar in globular clusters. Working with Thomas Prince I had a very productive program of pulsars in globular clusters (1987–1992). A chance encounter with astronaut and instrumentation expert Sam Durrance led to a collaboration which eventually resulted in the discovery of the first clear detection of a brown dwarf companion to a nearby star (1995). Desiring to learn X-ray astronomy I undertook a sabbatical to Japan, centered on the launch and commissioning of the ASCA X-ray mission. During this sojourn, I became familiar with gamma-ray burst phenomenology. I proposed that soft gamma-ray repeaters are of Galactic origin, possibly associated with plerionic nebulae. I returned to the US thinking of ways to make progress in gamma-ray bursts (GRBs).
In 1994, influenced by a paper by Paczynski & Rhodes, Dale Frail and I began a program to search for radio afterglow of GRBs. This program blossomed with the launch of the BeppoSAX satellite (1996). We discovered the first radio afterglow and, using the Keck Observatory, showed that GRBs are of not merely extra-galactic origin but cosmological origin. The period 1997–2003 was very fruitful with advances practically every month or so. Upon the launch of Swift X-ray Observatory, a dedicated mission for GRBs, in 2004, I decided to abandon the GRB field.
In Spring 2005 whilst teaching a graduate class on High Energy Astrophysics, I came to realize that the remains of neutron star merger are potentially detectable, but it would require wide-field optical imagers with good sensitivity. However, the rarity of the events meant that one must have a thorough command of the optical transient phenomenology. The Palomar Transient Factory (2009–2012) was designed for a systematic exploration of the dynamic optical sky. Thanks to Joshua Bloom, we were an early adopter of Machine Learning. Robotic spectroscopy was introduced in the intermediate Palomar Transient Factory (2013–2016). The culmination of this program was the Zwicky Transient Facility (ZTF) which saw first light in late 2017.
ZTF was so successful that the National Science Foundation in 2021 decided to fund it for an additional phase. With the funding secured for the second phase, I decided it was time to move on and hand over the project to younger colleagues. I am now working on gas between stars and separately with colleagues on the Ultraviolet Explorer (UVEX) which is expected to be launched in 2030.
12 November 2024 Hong Kong
