S. George Djorgovski is a Professor of Astronomy and Data Science at Caltech. He has worked on a wide range of subjects in astronomy, cosmology, and applications of data science in different fields.

In astronomy, his work with Hy Spinrad and others led to discoveries of the first radio galaxies known as redshifts z > 1, and the evidence for their strong evolution. His work with Ivan King and others led to the discovery of post-core-collapse of globular clusters, and systematic studies of their structure, dynamics, and stellar populations. He discovered the first known galaxy at z > 3 using the narrow-band Lyman alpha imaging, and with Dave Thompson conducted the most comprehensive searches for high redshift galaxies in the 1990s. With Georges Meylan and others, he discovered the first examples of binary quasars (and the first triple), and several tens of gravitational lenses and binary quasars since, most recently with the Gaia GrAL team, and examples of quasar clustering at high redshifts. With Marc Davis, he discovered the Fundamental Plane correlations for elliptical galaxies, and subsequently with Reinaldo de Carvalho, Mike Pahre, and others, its uses as distance indicator and a probe of the formative history of ellipticals.

Djorgovski was the PI of DPOSS, the digital version of the Second Palomar Sky Survey, one of the first projects to push astronomy into the Terabyte era. Working with Nick Weir, Usama Fayyad, Reinaldo de Carvalho, Steve Odewahn, Roy Gal, Julia Kennefick, Ashish Mahabal, Giuseppe Longo, and others, they pioneeded the use of Machine Learning for data analysis of large digital sky surveys, and a number of scientific projects, including catalogs of galaxies and clusters of galaxies, searches for z > 4 quasars and their luminosity fuction, and early time-domain searches for highly variable objects and optical transients in DPOSS plate overlaps.

Working with Shri Kulkarni, Dale Frail, and others, he obtained the first conclusive evidence that Gamma-Ray Bursts (GRBs) are at cosmological distances, and conducted systematic studies of their afterglows and host galaxies.

At the turn of the millenium, along with Alex Szalay, Tom Prince, Robert Brunner, Roy Williams, Matthew Graham, Ashish Mahabal, Giuseppe Longo, and others, he was one of the founders of the Virtual Observatory framework, including the International Virtual Observatory Alliance, and he was the Chair of the NSF-NASA National Virtual Observatory Science Definition Team. This was followed by the emergence of the new discipline of Astroinformatics, focused on the uses of Machine Learning and Artificial Intelligence based knowledge discovery tools, with the foundational conference at Caltech in 2010.

Exploration of the time domain astronomy commenced with new synoptic sky surveys, Palomar-Quest (in collaboratoin with Charles Baltay and the PQ team), Palomar Transient Factory and Zwicky Transient Facility led by Shri Kulkarni and others, and with the Catalina Real-time Transient Survey (CRTS), co-led by Djorgovski and Andrew Drake and involving Ashish Mahabal, Matthew Graham, Eilat Glikman, Ciro Donalek, Roy Williams, and others, detected and published electronically many thousands of transient and highly variable sources, enabling science ranging from the Solar system and variable stars to cosmic explosions and a rich phenomenology of quasar/AGN variability.

After founding the Center for Data-Driven Discovery at Caltech, along with Ashish Mahabal, Dan Crichton, Santiago Lombeyda, Matthew Graham, Ciro Donalek, and others, Djorgovski was active in data science methodology transfer to other fields, notably medicine and cancer research in particular. This included development of innovative data visualization tools, and led to the formation of a thriving startup, Virtualitics, Inc., with Michael Amori as the CEO, and Donalek as the CTO.

Palomar-Quest data were also used to create The Big Picture mural at the Griffith observatory, that has been seen by over 20 million visitors to date. Djorgovski was also exploring the use of virtual worlds as an educational, scholarly, and scientific platform, and has taught three MOOCs on Coursera and EdX.