Oldest Material On Earth Discovered

fahrbot-bot shares a report from the BBC: Scientists analyzing a meteorite have discovered the oldest material known to exist on Earth. They found dust grains within the space rock — which fell to Earth in the 1960s — that are as much as 7.5 billion years old. The oldest of the dust grains were formed in stars that roared to life long before our Solar System was born. A team of researchers has described the result in the journal Proceedings of the National Academy of Sciences. The team from the U.S. and Switzerland analyzed 40 pre-solar grains contained in a portion of the Murchison meteorite, that fell in Australia in 1969. Based on how many cosmic rays had interacted with the grains, most had to be 4.6-4.9 billion years old. For comparison, the Sun is 4.6 billion years old and the Earth is 4.5 billion. However, the oldest yielded a date of around 7.5 billion years old. Previously, the oldest pre-solar grain dated with neon isotopes was around 5.5 billion years old.