Even the most diligent stargazers catch only a minute fraction of the supernovas, variable stars, and other rapidly changing phenomena; there is simply too much sky to cover. But two ambitious new projects seek to fill in that gap in our cosmic understanding.
Jonathan Grindlay, an astronomer at Harvard University, leads the Digital Access to a Sky Century at Harvard program, which will digitize more than 500,000 glass plates—some showing as many as 100,000 stars—taken by telescopes around the world between 1880 and 1985. Then computer programs will sift through the huge database, looking at how quasars and gamma-ray bursts change over decades.
While Grindlay opens windows on the past, Caltech’s Shri Kulkarni is tracking the sky in real time. Kulkarni heads the Palomar Transient Factory, which searches for supernovas and other astronomical things that go bump in the night. The Samuel Oschin Telescope keeps a constant watch, taking around 40 gigabytes of scientific images every night. A computer alerts astronomers whenever it detects a change in a star’s brightness or an interesting object such as an unusually powerful supernova, so they can study it with larger telescopes. Project scientist Nicholas Law says the system may someday automatically coordinate with other telescopes to study such events before they fade away.