Astronomers have used the European Southern Observatory's Very Large Telescope (ESO's VLT) to study the composition of 3I/ATLAS, the brightest interstellar object ever seen, in detail. By measuring specific chemical fingerprints—the first observations of this kind for a comet that formed outside t he solar system—they found that 3I/ATLAS likely originated in the outskirts of an old star system. ...read more read less