For the first time astronomers have detected stars in an enormous stream of gas shed by the Magellanic Clouds, the two brightest galaxies that orbit our own.
Sought for decades, the newfound stars are young, which means they formed recently, while the Magellanic gas collided with gas in the Milky Way. The newborn stars offer insight into processes that occurred in the ancient universe, when small, gas-rich galaxies smashed together to give rise to giants like the Milky Way. “This is the one and only galaxy interaction we can model in very much detail,” says Dana Casetti-Dinescu, an astronomer at Southern Connecticut State University, who notes that other collisions of gas clouds between galaxies are farther away and thus harder to observe. “For more distant systems that interact, we don’t have the wealth of information.”
Although the stars owe their births to gas from the Magellanic Clouds, they now revolve around a new master: the Milky Way Galaxy, which has enhanced its already significant grandeur by grabbing gas from its two most flamboyant satellites and sculpting it into new stars, a process our galaxy must have exploited numerous times in ancient epochs as it grew into a giant.