GSoC/GCI Archive
Google Summer of Code 2011

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Astrometry = "astro" (celestial objects) + "metry" (measurement)

Astrometry is the branch of astronomy that deals with measuring the positions and motions of celestial objects (stars, galaxies, planets, comets, and so on). is a project and our goal is to allow astronomers of all levels (professional researchers, tech savvy amateurs, and backyard stargazers) to share and learn from each other's astronomical images. A barrier that we are trying to eliminate is the problem of calibrating images -- figuring out the properties of the camera and where it was pointing, so that we can make sense of the image. We have built an "astrometry engine" -- a piece of code that can recognize the celestial objects in an astronomical image and figure out where the camera was pointing. You take a picture of the night sky, and our software can automatically figure out where your camera (or telescope) was pointing, based on the geometric arrangement of the stars in the image.

It's a computer vision system that *works* -- a cool trick! Exactly what does the astrometry engine produce? A mapping, or transformation, between image coordinates and sky coordinates. Does it work? Yeah! The system can recognize 100% of the 300,000+ images in the Sloan Digital Sky Survey.

We have been running a web service for over three years and have successfully recognized tens of thousands of images. We also run a group on flickr -- the images submitted to the group automatically get fed into the astrometry engine and tags are added to the images identifying their contents. Professional observatories and amateur astronomers are using our code for pointing their telescopes and analyzing the results. We've got a strong technical base, but we want your help to expand our operations, improve our web presence (build a web service that doesn't look like the ugliest thing on the web in 1994!), build a community, reach out to a broader user base (eg, build a tool that lets you plug a digital camera into your laptop and tells you where to point it to find stuff in the sky), and do cool things with the collection of images our users have assembled (build a dynamic map of the sky and a list of the objects in it).


  • Community Platform Update the web service at, by "reframing" the service within the Django framework, and creating user profile registration capability to the service.
  • New Web Service Front-end (+ API) This project involves designing and implementing a new web interface for the service. This new webpage should be feature-rich, easy to use, and relatively "pretty" in order to attract new users and help promote a thriving community around The web interface will be built in python, using Django.