by Alex Fox/Smithsonianmag.com
Scientists studying a hunk of Earth’s crust gathered from deep in the Pacific Ocean have discovered traces of rare forms of plutonium and iron whose chemical makeup suggests they were forged in powerful collisions or explosions in outer space before falling to Earth, reports Nell Greenfieldboyce for NPR.
For many years, the predominant hypothesis was that heavy elements such as gold, silver, platinum, uranium and plutonium were created by the violent deaths of stars, called supernovae, reports Emily Conover for Science News. But a new study, published this week in the journal Science, suggests that ordinary supernovae aren’t enough to explain all the heavy elements researchers have identified in Earth’s vicinity.
Instead, the paper proposes that other interstellar events such as the collision of two super-dense collapsed stars, called neutron stars, or certain rare types of supernovae, according to Science News.
“It’s amazing that a few atoms on Earth can help us learn about where half of all the heavier elements in our universe are synthesized,” Anton Wallner, a nuclear physicist at the Australian National University as well as the Helmholtz Center in Germany and the paper’s first author, tells William J. Broad of the New York Times.