February 23 - The LSST Revolution

Our speaker this week was Federica Bianco, a research scientist at both New York University's Center for Urban Science and Progress and their Center for Cosmology and Particle Physics. Her work focuses on transients - temporary changes in the sky. She is also the chair of the Large Synoptic Survey Telescope (LSST)'s Transients and Variable Stars Collaboration.

Federica's talk revolved around how the survey program of LSST will revolutionize our understanding of the changing universe, also known as time-domain astronomy. In particular, current studies tend to be at most two of wide (covering a large area of the sky), deep (observing faint objects) and fast (repeatedly observing the same place in quick succession). LSST is the first survey to attempt all three of these simultaneously by observing the entire Southern sky from its mountaintop in Chile, cataloging objects about 100 times fainter than current surveys with such a wide area, and imaging each patch of sky about once every three days -- with five different color filters.

LSST can achieve this due to its unique optical design that gives it an enormous field of view -- equal to the size of about 40 full moons -- and a 3,200 megapixel camera. This giant sensor will generate 15-20 terabytes of data a night, which will be immediately piped up to University of Illinois National Center for Supercomputing Applications in Urbana-Champaign, Illinois. There, the goal is to process each image and release in less than 60 seconds, including comparisons to previous data and generating an estimated 10 million science alerts per night. Just storing the 50-100 petabytes of data generated during its 10-year survey will be an immense challenge! Another amazing property of the LSST data is that it will be public immediately to all people in the US, so anyone interested can see what's happening in the sky almost in real time.

Federica also described the diverse science goals of LSST, which include understanding the nature of dark matter and characterization of dark energy; mapping the Milky Way; cataloging the Solar System; and exploring the changing sky. Many more details about LSST and its goals are available on its website.

After her talk, Federica answered questions in the lecture hall. Later, American Museum of Natural History fellow Betsy Hernandez gave a presentation on Active Galactic Nuclei while Columbia undergraduate Richard showed presentations on the 3D Wall and graduate students Daniel, Aleksey, and Adam gave tours of the observatory.


- David Hendel (graduate student)