Andrew J. Connolly, Professor

ajc pic

Contact Information

Email: ajc@astro
Office : B355
Phone : 206.543.9541
Fax : 206.685.0403
Dept. of Astronomy
University of Washington
Box 351580
Seattle, WA 98195-1580

Shipping Address:
3910 15th Ave NE
Seattle, WA 98195-1580

Research Group

  • Scott Daniel
  • Simon Krughoff
  • Jake Vander Plas
  • Yusra AlSayyad
  • Bryce Kalmbach
  • Andy Becker
  • Russell Owen

Former Members

  • Ryan Scranton
  • Alberto Conti
  • Jeff Garner
  • Dan Vanden Berg
  • Ching-Wa Yip
  • Sam Schmidt
  • Joerg Colberg
  • Jeremy Brewer
  • Niraj Welikala
  • Cameron McBride
  • Jim Pizagno
  • Rob Gibson
  • Nicole Silvestre

About Me

I arrived at UW in the summer of 2007 after spending some years on the faculty of the University of Pittsburgh and before that at the Johns Hopkins University. This must mean that I am not afraid of cloud as both Pittsburgh and Seattle share the same number of clear days per year (not many). I work principally on large astronomical surveys such as the Sloan Digital Sky Survey and the Large Synoptic Sky Survey. I currently run the UW data management group for LSST which works on developing software analyzing the data that will come out of the LSST and I also run the LSST simulation group which is developing high fidelity simulations of what we expect to see with LSST. My science focuses on analyzing large astronomical data sets to study the formation and evolution of galaxies and cosmology using techniques such as photometric redshifts.

Research Interests

Scalable Science

Cloud computing has revolutionized the way business is done on the Internet. By linking hundreds to thousands of computers together with Petabyte data storage, massively intensive (in both data and computation) tasks can be addressed. Astronomy is facing many of these issues with the next generation of surveys producing Petabytes of catalogs and tens of Petabytes of images. We work on how to make science easily scalable which represents a departure from traditional thinking in the area of high performance computing in which the data, CPUs, and memory all reside on the same physical machine with fast communication between all components. Instead the processing units only have access to a small amount of local storage and can be considered to be isolated from the other compute nodes in the cluster. Our Cluster Exploration (CluE) initiative work is a joint effort between NSF, Google, and IBM to develop tools for astronomy that can work on large compute resources.


The Large Synoptic Survey Telescope will produce the largest digital map of the sky. Imaging half the sky every three nights it will produce over 20 TB of images each night and 1 Petabytes of catalog data per year. My interests in LSST focus on weak lensing (in particular mass tomography using photometric redshifts), algorithms for analyzing this massive data stream and high fidelity simulations (working with John Peterson and Garrett Jernigan). The Image Simulation Group provides high fidelity end-to-end simulations of the sky. These simulated images and catalogs extend to r=28 (deeper than the expected 10 year depth of the LSST coadded images) and are used in: designing and testing algorithms for the use by the data management groups, evaluating the capabilities and scalability of the reduction and analysis pipelines, testing and optimizing the scientific returns of the LSST survey and providing realistic LSST data to the science collaborations to evaluate the expected performance of LSST.

Google Sky

In 2006 I was on sabbatical at Google where I was project lead for Google Sky which put astronomical images, taken from a wide range of telescopes (from the Hubble Space Telescope, Sloan Digital Sky Survey and the Digitized Sky Surveys), into Google Earth. Sky was released in August 2007 and at UW we maintain an interest in using these visualization tools in research and education. A range of add-ons that have been created at UW for Google Sky can be found here or you can check out the movie that combines image simulations for LSST with Google Sky.

Zoom into a simulated image embedded in the SDSS imagery (using Google Sky). Download animation [24 MB MPEG4]


We also use Google Sky in a browser (as a widget) and add other widgets that can query the SDSS archive or resolve the name of source into a position on the sky. Unlike iGoogle where all of the widgets are independent our science tools all communicate to each other so when we query for galaxies we can see the points overlaid on the sky or color the points based on their g-r colors. This interactive framework can be customized to however you want to see the sky.

Accessing the sky through a browser. Download animation [23 MB Quicktime]