“Holy cow, this is really bad,” radio astronomer Mark Reid said when informed by ScienceInsider that the telescopes were going offline. “If they don’t operate the telescopes, it could mean a year’s worth of data becomes useless.” And it would be a costly loss, he adds, estimating that the data cost $500,000 to collect.

Reid is a U.S. government employee who works for the Smithsonian Astrophysical Observatory, part of the Harvard-Smithsonian Center for Astrophysics in Cambridge, Massachusetts. Like hundreds of thousands of other federal workers, he’s been at home since the shutdown began on Tuesday. Meanwhile, he’s been trying to use some of his time off productively, thinking about his collaborative work with an international team on measuring and mapping the great spiral arms of the Milky Way.

Twice a year, Reid and his colleagues use the Very Long Baseline Array (VLBA)—a string of 10 sensitive radio telescopes stretching 8600 kilometers from Hawaii to the Virgin Islands and New England—to help make measurements from Earth to massive gas clouds surrounding about 50 newborn stars in the galaxy. The VLBA measurements, made in the spring and fall, allow the team to calculate distances to the stars and construct a map of the galaxy. The map’s accuracy, however, depends on comparing three sets of VLBA measurements taken over 18 months.