NASA's Nancy Grace Roman Telescope will hunt for the universe's first stars — or rather, what's left of them after they've been ripped apart by black holes.
NASA's forthcoming Nancy Grace Roman Telescope could use the grisly death of stars ripped apart by black holes to hunt the universe's first population of stellar bodies. These early stars, referred to (somewhat confusingly) as Population III (Pop III) stars, were very different from the sun and other stars seen in the cosmos today. That's because the universe wasn't yet filled with "metals," the term astronomers use to describe elements heavier than hydrogen and helium. Pop III stars arose just a few hundred million years after the Big Bang and were "metal-poor," composed mostly of hydrogen and helium. They were also believed to be much larger and hotter than the sun. This means that Pop III burned through their fuel for nuclear fusion faster than smaller stars, and these short lifetimes make them elusive targets for astronomers. Because these earliest stars are responsible for forging metals that would become the building blocks of the next generation of less-metal-poor stars, studying them is key to understanding cosmic evolution. New research suggests that the Nancy Grace Roman Telescope (or Roman for short), set to launch in 2027, could have a unique way of doing this. Related: Astronomers witness 18 ravenous black holes ripping up and devouring stars Rather than looking for intact Pop III stars, Roman will search for what remains of them after they have strayed too close to black holes and been destroyed in occurrences that astronomers call tidal disruption events, or TDEs. "Since we know that black holes likely exist at these early epochs, catching them as they're devouring these first stars might offer us the best shot to indirectly detect Pop III stars," study team member and Yale University scientist Priyamvada Natarajan said in a statement. Roman will watch the destruction of the first stars When a star passes close to a black hole, the tremendous gravitational influence it encounters generates immense tidal forces within…