7 billion years: Scientists say oldest solid material found

An undated handout picture shows a scanning electron micrograph of a presolar silicon carbide grain. [Janaína N. Ávila/AFP / Janaína N. Ávila]

Researchers said Monday that new techniques have allowed them to identify the oldest solid material ever found on earth.

The stardust, formed five to seven billion years ago, came from a meteorite that fell to Earth 50 years ago in Australia, they said in a paper published in the journal PNAS.