Astronomers have previously identified stars to be extremely energetic during their early lives, but they were not sure about the sun's behavior during its juvenile stage.
Now, ancient and rare blue crystals called the hibonite from about 4.5 billion years ago confirmed that the sun used to be as hyperactive. Think of the sun with the energy of a three-year-old kid, except that the sun was just a newborn when it behaved like a toddler.
As a juvenile star, the sun erupted habitually, churning out voluminous high-energy particles. The ancient blue crystals trapped in meteorites revealed this rowdy behavior. These minerals may probably be the first minerals formed in the Solar System, according to the scientists with the University of Chicago, the Field Museum, and ETH Zurich, who performed the study on the hibonite.
Ancient Blue Hibonite Crystals
For their study, published in Nature Astronomy on July 30, the scientists examined the chemical reactions that took place in the creation of the microscopic ice-blue crystals. Their analysis revealed that as the sun spewed loads of energetic particles, some of the protons hit the calcium and aluminum in the blue hibonite crystals. The force caused the atoms to split into tinier atoms of neon and helium.
The neon and helium particles were trapped inside the hibonite for billions of years, merging in the space rocks where scientists have discovered them.
The larger mineral grain found in space rocks are usually only a few times larger than the diameter of a human hair, said Andy Davis, co-author for the study. When the team examined these particles, the hibonite stood out as the tiniest light blue crystals.
Levke Kööp, the lead author of the study, explained that hibonite crystals measure less than 100 microns across. Even with this minuscule size, however, Kööp said the ancient blue crystals were able to retain the highly volatile gases produced by the young sun's erratic behavior billions of years ago.
The Hyperactive Juvenile Sun
The young sun, in its days before the planets were formed, contained a massive disk of gas and dust that spiraled around the Solar System. The sun at this time was hot, more than 2,700 degrees Fahrenheit. Venus, in comparison, can already melt lead with its temperature of 872 degrees Fahrenheit.
When the sun's disk of gas and dust calmed down, the blue hibonite crystals were eventually formed. Unlike the more tranquil adult sun that people knew now, the juvenile sun had, however, kept on shooting its loads of high energy, hitting the crystals over and over again, causing the chemical reactions to happen for numerous times.
"It'd be like if you only knew someone as a calm adult — you'd have reason to believe they were once an active child, but no proof. But if you could go up into their attic and find their old broken toys and books with the pages torn out, it'd be evidence that the person was once a high-energy toddler," explained Philipp Heck, one of the authors of the study.