A galactic visitor entered our solar system last year—interstellar comet 2I/Borisov. When astronomers pointed the Atacama Large Millimeter/submillimeter Array (ALMA) toward the comet on 15 and 16 December 2019, for the first time they directly observed the chemicals stored inside an object from a planetary system other than our own. This research is published online on 20 April 2020 in the journal Nature Astronomy.
Source:
https://phys.org/news/2020-04-alma-reveals-unusual-composition-interstellar.html