Scientists are analyzing billions of years old isotopes taken from asteroid fragments to determine when the solar system was formed.
The solar system formed in a short period of 200,000 years, Phys reported on November 13. The team at Lawrence Livermore National Laboratory (LLNL) came to this conclusion after studying isotopes of the element molybdenum (Mo) found in several meteorite fragments.
The material that makes up the Sun and the other celestial bodies in the system comes from a large cloud of gas and dust that collapsed 4.5 billion years ago. Looking at other star systems with similar formations, astronomers estimate that it would take 1 to 2 million years for a cloud to collapse and a new star to be born. However, this is the first study to provide data on this process in the solar system.
“Before, we didn’t really know how long it took to ‘design’ the solar system. New research shows that the collapse event that led to the formation of the solar system happened very quickly, just in time. If you compare the life cycle of a human, the time it takes for the solar system to form is equivalent to a pregnancy of just 12 hours instead of 9 months, ”says Greg Brennecka, space chemist at LLNL.
The oldest solids in the solar system are calcium-aluminum rich mixtures (CAI). They keep information about the appearance of the solar system. CAI samples vary from a few micrometers to several centimeters in an asteroid fragment formed in high temperature environments (over 1000 degrees C), possibly near the young sun. They are then transported to the exterior where chondrite C type meteorites are born. Most CAIs formed 4.567 billion years ago, over a period ranging from 40,000 to 200,000 years.
The LLNL team of scientists studied molybdenum (Mo) and trace elements in numerous CAI samples collected from fragments of the C-chondrite meteorite, including Allende, the largest fragment of the C-chondrite meteorite on Earth. They discovered that the Mo isotopes of CAI cover all the material formed in the protoplanet plate instead of a small fraction. Therefore, they must form when clouds collapse.
