Star formation sets the conditions for the formation of planets and origin of life. On large scales, massive stars drive the evolution of galaxies. The formation of massive stars is a fundamentally important yet unresolved problem in astrophysics. In particular, the initial conditions are not well known due to a lack of in-depth observations. This has led to different assumed initial conditions in debating theoretical models. Thanks to recent multi-wavelength surveys, it is finally feasible to make a Galaxy-wide census of massive clumps (precursors to high-mass star clusters) using high-resolution deep ALMA observations. I present our series studies on infrared dark clouds (IRDCs) that pioneered in characterizing the earliest stages during massive star formation. Built on these, I show how our carefully designed ALMA surveys of starless IRDCs can uncover deeply embedded core populations for robust cross comparison, and thereby can single out the truly initial conditions across the Galaxy. In the next 5-10 years, we expect that these combined efforts will give definitive answers to key questions in high-mass star formation, and motivate the next generation of star formation models.

BIO
Dr. Ke Wang is an associate at the European Southern Observatory (ESO) headquartered in Germany, and a grant holder of the German Research Foundation (DFG). His main research interest is the early phase of massive star formation, from Planck cold cores, infrared dark clouds to interstellar filaments. His recent research on the largest filaments ("Bones") in the Milky Way has been featured by Harvard, American Astronomical Society, and European Space Agency. His studies on the initial fragmentation in star cluster forming regions have been highlighted in Annual Review in Astronomy and Astrophysics (ARAA) and review Protostars and Planets VI.
He is an enthusiastic observer with expertise in radio interferometers, including the Atacama Large Millimeter/submillimeter Array (ALMA), the Jansky Very Large Array (JVLA), and the Submillimeter Array (SMA). He received his Ph.D. degree from Peking University in 2012. Majority of his Ph.D. program was carried out at the Harvard-Smithsonian Center for Astrophysics (CfA) during an SMA pre-doctoral fellowship. In 2011, he accepted a research grant of the European Commission and moved to the Kapteyn Astronomical Institute in the Netherlands for a postdoctoral fellowship. He joined ESO in 2012 as an ESO fellow and became an associate in 2015. His Ph.D. thesis was awarded the Springer Theses Prize. He was a member of the Chinese delegation at the 62nd Lindau Nobel Laureate Meeting.