Meteorites have always been an essential part of research for scientists as it allows them to peer into the distant regions of the universe. Recently, a new study has identified the oldest thing ever found on Earth. Scientists discovered 7-billion-year-old stardust trapped inside a meteorite that fell fifty years ago in Australia.
We know that stars have life cycles. Stars born when bits of dust and gas floats through space, find each other and collapse in on each other and heat up. Their life span can be millions to billions of years, and they die. When they die, the bits of stardust eventually form new stars, along with planets and meteorites. Some of the dust sometimes enters the earth's orbit.
However, the way to discover the date of the grains is quite impressive. Researches determine it by seeing how much they had been battered with cosmic rays. Cosmic rays are high-energy particles that fly through the Milky Way galaxy and penetrate solid matter.
A researching team led by Philipp Heck at the Field Museum in Chicago examined what is known as "presolar grains," or minerals formed before the sun was born. "Presolar grains are the oldest datable solid samples available and provide invaluable insight into the presolar chronology of our galaxy," explained the researchers.
Heck expressed his excitement while describing the findings. "These are the oldest solid materials ever found, and they tell us about how stars formed in our galaxy." The presolar grains are rare and found only in five percent of meteorites that have fallen to earth. The scientists believe that these discoveries would help us by providing a better scope to understand the mystery of the galaxy and how it developed.
"It's so exciting to look at the history of our galaxy. Stardust is the oldest material to reach Earth, and from it, we can learn about our parent stars, the origin of the carbon in our bodies, the origin of the oxygen we breathe," explained Heck.
"With this study, we have directly determined the lifetimes of stardust. We hope this will be picked up and studied so that people can use this as input for models of the whole galactic life cycle," Heck says.