The oldest material on Earth is 7 billion year old stardust that originates from the Murchison meteorite. The Murchison meteorite first fell in Australia in 1969. It was a 220-lb. rock that fell near Murchison, Victoria in Australia.
Scientists studied the silicon carbide dust particles from the Murchison meteorite to determine that the particles were 7 billion years old which is older than the Earth itself and the Sun.
In order to analyze the dust particles, scientists ground a small part of the Murchison meteorite into powder. They then separated the stardust from other components in the meteorite by its chemical composition.
The grains of dust showed signs that they had traveled the galaxy in large clusters. Some of the grains were found to be one billion to three billion years older than the Sun. Hence, these stardust grains definitely originated in a time before the Sun was born.
Scientists believed that the stardust on the Murchison meteorite originated from dying stars in the universe. The dust collected onto the asteroid that produced the Murchison meteorite as it headed towards Earth.
Scientists estimate that the grains of dust originated from dying stars that were two to three times the mass of the Sun.
Moreover, scientists discovered about 14,000 molecular compounds including 70 amino acids in a sample of the meteorite.
The 7 billion year old stardust can be used by scientists to learn about the historical origin of parent stars and the time period before the existence of the Sun.