Two teams of astronomers have performed polarimetric observations of 2I/Borisov, the first active extrasolar comet ever detected in our Solar System, using ESO’s Very Large Telescope (VLT) to derive the physical characteristics of its coma dust particles; they’ve also obtained high-resolution interferometric observations of 2I/Borisov with the Atacama Large Millimeter/submillimeter Array (ALMA) and multi-color optical observations with VLT to...