On March 16, 1950, astronomers at the US Naval Observatory pointed a telescope roughly in the direction of the constellation Lupus the wolf and took a picture. When scientists look at that same patch of sky today, something is missing. Back in 2016, researchers in Sweden reported that a star had been lost. One of the roiling distant suns visible in that USNO image from the previous century could no longer be seen. The team published a paper on the discovery, but called it "very uncertain" at the time, resolving to do more follow-up work and to continue scouring old USNO observations for other celestial objects that seem to have gone missing. Three years later, it's still unclear what happened to that star spotted in 1950, but the team behind the "Vanishing & Appearing Sources during a Century of Observations" (Vasco) project now says they've found a hundred more missing stars like it by comparing old and new observations. While they've seen no signs of aliens just yet, they say parts of space where multiple stars seem to disappear could be the best places to look for extraterrestrial intelligence (ETI). "Unless a star directly collapses into a black hole, there is no known physical process by which it could physically vanish," explains a new study published in the Astronomical Journal. "The implications of finding such objects extend from traditional astrophysics fields to the more exotic searches for evidence of technologically advanced civilizations."