An article published in the journal “Nature Astronomy” reports the detection of gamma-ray eclipses in binary systems formed by a normal star or a brown dwarf that have a pulsar as a companion that is defined as a spider pulsar because they steal gas from the companion behaving like a black widow. A team of researchers used data collected over a decade by NASA’s Fermi Space Telescope to find cases in which the star passes in front of the pulsar. Seven binaries have been identified with a spider pulsar being eclipsed by its companion. This identification made it possible to measure the pulsar’s mass, a result useful to conduct tests on the theory of relativity and understand the behavior of matter in extreme conditions.