Scientists have discovered that microscopic dust particles extracted from meteorites that landed on Earth were of an ancient and explosive origin.
Dust particles, also known as sunflower grains (since they are older than our Sun), were probably thrown out by stars that exploded hundreds of millions of years before the Earth’s solar system was formed. And studying new data from these tiny particles, the researchers came closer to the identifying type of a stellar explosion, which produced dust 5 billion years ago.
In order to trace the origin of the subatomic “fingerprints” of star dust, scientists created computer models that simulate the explosive conditions that could produce them. This helps to check whether the point of origin of the dust particles is possible by the explosion of a white dwarf in a binary stellar system.
According to the author of the study, Christopher Wrede, this study is complemented by decades of analysis of the mysterious phenomena of the age and origin of these solar stars. Wrede, an assistant professor of physics at the University of Michigan, told Live Science in an email that researchers study grain isotopes, variations of an element with a different number of neutrons. About a dozen grains had a lot of silicon-30 isotope, which was associated with a certain type of star explosion, called the classical new (new star).
Classic new ones are stellar eruptions, occurring in binary form or paired stellar systems - differ from supernovae. According to research, they represent a type of explosion that can happen again and again. A smaller star in a pair, a white dwarf, steals fuel from its larger neighbor, heating its own surface and, eventually, spewing dust and gas into outer space.
Being a classically new star, the white dwarf can continue to pump out fuel from its neighbor and light up again, ”Wrede said. “An entire star explodes in a supernova so that it can only happen once.”
When the Solar System was formed, the collisions heated and mixed the building blocks of dust and gas, preparing them evenly so that they shared most of the same isotopes. Grains with unusual isotopes (as in the case of silicon-30, which are rarely found on our planet) stand out, ”Vrede explained. “This suggests that they should have been produced before the formation of the solar system,” dating back about 5 million years, said Wrede. According to Wrede, high rates of silicon-30 compared to other silicon isotopes in the grains suggest that they originated in a classic new star. But he and his colleagues were not sure how much silicon-30 they could see with respect to other isotopes, if the classical new was responsible for this. Their experiments have demonstrated to everyone a new path for a nuclear reaction, which may affect the amount of silicon-30 production, and also help determine if a certain amount of silicon-30 in dust particles is just a coincidence.
“The path seems reliable, but we have to do a series of experiments to find out how reliable it is,” said Wrede Living Science.