The structure of our solar system can be explained by a period of orbital instability experienced by the giant planets. And even though they thought it was relatively late, the researchers now estimate that this instability occurred in the hundred million years after the solar system was formed.
Ourformed from a giant and from . Among the This hypothesis has been accepted for some time. And until recently, the researchers imagined that the configuration we know today took about 700 million years. But from the University of São Paolo (Brazil) argue today that everything could be played much faster.
Astronomers explain that the fourfrom ours – – , , and – first appeared more compact. Beyond the current orbit of Neptune and Uranus was a large amount of planetesimals. And it was these small rock and ice bodies that started to disrupt the established gravitational balance. The beginning of a period of instability, chaos, when the giant planets were launched in your area. and planetesimals were pushed into what astronomers call it today , a region between 30 and 50 times the distance between ours and the . In parallel, all of the planets have moved into orbits farther from the sun.
Until recently, astronomers imagined thishad occurred late. Especially because the dating of the rocks from the through missions had made him think. But now the established chronology doesn’t seem so certain anymore.
The key would be hidden between Neptune and the planetary disk
According to researchers from the University of São Paolo, the instability period could only occur late if the distance between the planetesimal disc and thewas great. And so the gravitational influence of these rocks was weak. And to get to the point, they decided to model this slice of planetesimal by going back to a time when Neptune and Uranus were still growing.
Jupiter and Saturn were formed, but instead of Neptune and Uranus there were five to ten. Bodies that are up to five times as massive on our planet. And these eventually collided to give birth to the last two giant planets. A part of was also used to build Neptune and Uranus and another part was thrown away. It would therefore be the growth of these two giant planets that would have defined the boundary of this disc.
In summary, it can be said that the gravitational interaction between theand the planetesimal disk produced perturbations in the gas disk which spread in the form of waves. These waves were the origin of compact planetary systems and . When the gas ran out, the interaction between the planets and the planetary disc disrupted the synchronicity and started the chaotic phase.
Instability occurred in the first hundred million years
In view of all of this, researchers from the University of Sao Paolo believe that the conditions for the distance between the orbit of Neptune and the inner boundary of the planetesimal disk simply did not exist to become large enough to support the hypothesis of late instability. According to them, the instability occurred in the first hundred million years and may have occurred before the earth and moon were formed.
What you should remember
- The structure of our solar system is the result of gravitational instability that astronomers thought was late.
- But today they provide evidence that these events could have happened much earlier.