ALMA captures distant colliding galaxy dying out as it loses the ability to form stars

(ESO) Galaxies begin to "die" when they stop forming stars, but until now astronomers had never clearly glimpsed the start of this process in a far-away galaxy. Using the Atacama Large Millimeter/submillimeter Array (ALMA), astronomers have seen a galaxy ejecting nearly half of its star-forming gas. This ejection is happening at a startling rate, equivalent to 10 000 Suns-worth of gas a year. The team believes that this event was triggered by a collision with another galaxy.