Our universe’s first galaxies shone hotter and brighter than scientists thought, according to a group of astronomers who tapped a whopping 400 hours of observing time on NASA’s Spitzer Space Telescope. The discovery could answer a long-standing question about how light first traveled freely through the infant universe.

“We did not expect that Spitzer, with a mirror no larger than a Hula-Hoop, would be capable of seeing galaxies so close to the dawn of time,” study author Michael Werner sa