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TV Program on Discovery Channel

quasar formation
Formation of a luminous quasar at z~6.5 through hierarchical galaxy mergers in the early Universe.

In September 2008, I provided a spectacular movie of the birth of a luminous quasar at redshift z~6.5 , for the Disc overy Channel in the program of "Cosmic Collisions". The images are projected densities of gas and stars. The gas is color-coded by temperature (blue indicates cold, yellow indicates hot, tenuous gas), the stars are color-coded by specific star formation rate (blue indicates active star forming). The artistic rays of the black holes (whose strength is proportional to the BH bolometric luminosity) indicate the accretion activity. This movie shows the formation of a luminous quasar at z~6.5 in the LCDM cosmology. It forms in a massive halo, and grows through hierarchical mergers of gas-rich galaxy progenitors. (Credit: Li et al. 2007, ApJ 665, 187)

Space shows

During my graduate years at Columbia University, I worked with advisor Mordecai Mac Low at American Museum of Natural History and made good use of our scientific research, contributing significantly to two thrilling space shows, "Search for Life" and "Cosmic Collisions" , produced by AMNH. They are being shown globally and have reached millions of people.

life
I provided simulations of ionization of molecular clouds by young stars, which tells when a star is formed.

In "Search for Life" (2003), I provided simulations of ionization of the turbulent molecular clouds by young stars, in collaboration with Mordecai Mac Low and Tom Abel (Li et al, 2004, ApJ 610, 339, astro-ph/0407249). Observation of the ionized region with H_alpha line gives important information of the formation of a star.

collisions collisions
I provided simulations of galaxy mergers of Milky Way and Andromeda, which is a major part of this show.

In "Cosmic Collisions" (2006), I provided simulations of galaxy mergers of Milky Way and our neighbor Andromeda, in collaboration with Mordecai Mac Low and Ralf Klessen (Li et al, 2005, ApJL 620, 19, astroph/0407248). My simulation is a major part of the show. This simulation benifited from the most advanced progress at that time: the highest resolution possible run on 64 processors at the Pittsburgh Supercomputing Center around the clock for almost a month, and the use of "sink particles" to represent star clusters formed during the merging event.

These two space shows have received rave reviews, and are viewed by thousands of people everyday around the world (I have also helped translate these two shows into Chinese).

merger
The merger of Milky Way and Andromeda from my simulation with Mordecai, rendered by the AMNH artists.



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