Astronomers have long sought out the sun’s “siblings,” stars born from the same cloud of gas and dust, because of the clues they’d provide regarding the sun’s origins. For years, the prevailing wisdom suggested that the sun was born in a sparsely populated “suburban” star-forming region about 5 billion years ago, along with roughly 3,000 other stars. (In contrast, densely populated “urban” regions can hold millions of stars.) The sun’s birth environment couldn’t have been too crowded, the logic went, because planetary systems, like ours, could never survive the gravitational jostling of neighboring stars in urban clusters.
But what if that’s wrong? Mark Krumholz, an astronomer at the University of California at Santa Cruz, realized that questioning the untested common wisdom about the sun’s suburban upbringing might mean it’s easier…
