By examining microscopic ice-blue crystals of mineral hibonite trapped inside a carbonaceous chondrite meteorite, an international team of scientists was able to figure out what the Sun was like before the Earth formed.
The team studied material from the Murchison meteorite, named after the Australian town near which it fell.
Using a unique state-of-the-art mass spectrometer in Switzerland, the researchers found hibonite crystals — many are less than 100 microns across — trapped inside the meteorite.
These tiny crystals formed over 4.5 billion years ago and their composition bears earmarks of chemical reactions that only would have occurred if the early Sun was spitting lots of energetic particles.
“These crystals preserve a record of some of the first events that took place in our Solar System,” said study lead author Dr. Levke Kööp, a postdoctoral researcher at the University of Chicago and an affiliate of the Field Museum.
“And even though they are so small, they were still able to retain highly volatile noble gases that were produced through irradiation from the young Sun such a long time ago.”
In its early days, before the planets formed, the Solar System was made up of the Sun with a massive disk of gas and dust spiraling around it. The region by the Sun was hot (over 1,500 degrees Celsius, or 2,700 degrees Fahrenheit).
As the disk cooled down, the earliest minerals began to form — blue crystals of hibonite.
When the crystals were newly formed, the young Sun continued to flare, shooting protons and other subatomic particles out into space. Some of these particles hit hibonite crystals.
When the protons struck the calcium and aluminum atoms in the crystals, the atoms split apart into smaller atoms — neon and helium. And the neon and helium remained trapped inside the crystals for billions of years.
“The Sun was very active in its early life — it had more eruptions and gave off a more intense stream of charged particles. I think of my son, he’s three, he’s very active too,” said co-author Professor Philipp Heck, from the University of Chicago and the Field Museum.
“Almost nothing in the Solar System is old enough to really confirm the early Sun’s activity, but these minerals are old enough. They’re probably the first minerals that formed in the Solar System.”
The findings appear online this week in the journal Nature Astronomy.
Source: Sci News