Free Astronomy Magazine November-December 2023

36 NOVEMBER-DECEMBER 2023 ASTRO PUBLISHING ESO telescopes help unravel pulsar puzzle by ESO Bárbara Ferreira W ith a remarkable observa- tional campaign that in- volved 12 telescopes both on the ground and in space, includ- ing three European Southern Obser- vatory (ESO) facilities, astronomers have uncovered the strange behav- iour of a pulsar, a super-fast-spin- ning dead star. This mysterious object is known to switch between two brightness modes almost con- stantly, something that until now has been an enigma. But as- tronomers have now found that sudden ejections of matter from the pulsar over very short periods are re- sponsible for the peculiar switches. “We have witnessed extraordinary cosmic events where enormous amounts of matter, similar to cosmic cannonballs, are launched into space within a very brief time span of tens of seconds from a small, dense celes- tial object rotating at incredibly high speeds,” says Maria Cristina Baglio, researcher at New York University Abu Dhabi, affiliated with the Ital- ian National Institute for Astro- physics (INAF), and the lead author of the paper published in Astron- omy & Astrophysics . A pulsar is a fast-rotating, magnetic, dead star that emits a beam of elec-