Timothy Beers, the Notre Dame Professor of Astrophysics, was interviewed on this week's episode of Big Picture Science. Big Picture Science is a nationally syndicated radio talk show produced by the SETI Institute in Mountain View, Calif. and broadcast nationally on NPR.
Beers spoke about his work using ancient stars in the Milky Way to reconstruct the abundances of chemical elements in the early universe. He noted that elements heavier than lithium, including most of those necessary for life (carbon, nitrogen, oxygen, etc) were not produced in the Big Bang, but rather inside stars as they lived and died.
There has been a long-standing mystery, only recently solved, about how long it took for enough of these elements to be formed to create the conditions for life. "We now know," said Beers, "that the earliest stars in the universe were so efficient at building these key elements that there was no chemical limitation to building life after the first several hundred million years.”
Evidence for this claim is found in the oldest stars in the Milky Way, which act as scribes, recording the chemical history of the galaxy. These old stars are so rare that they are only found by sifting through millions of other stars, a process that requires a marriage of modern telescopes and high-speed, high-throughput computing. One of those stars, discovered by Beers and collaborators, is BD+44°493. This star, which was born when the Milky Way was still in its infancy and long before the Earth formed, is visible using a pair of binoculars or an amateur telescope, and may well be the oldest object that a person on Earth can ever hope to see with their own eyes.
This episode of Big Picture Science will air locally on WVPE (88.1 FM) on Sun., Jun. 14 at 7:00 a.m. For those outside of Michiana, please check your local listings for show times or download the podcast at online.
Originally published by at physics.nd.edu on June 10, 2015.