Astrophysics postdoctoral researcher Dustin Lang and a
colleague had the bright idea to plug Internet-collected photographs of Comet
17P/Holmes into Astrometry.net to create this striking image of the comet's
trajectory. The site analyzes patterns of stars in photos and calibrates what
part of the sky is shown.
Photo by Dustin Lang (Princeton) and David W. Hogg (New York University)