A group of people in China and France have come up with a new theory that could help solve the mystery of how our solar system evolved. How did the gas giants end up where they are?
There is a chance that a fifth gas giant is 50 billion miles away.
Our solar system has not always looked the way it does today. Over the course of its history, the planets have changed dramatically, according to an assistant professor in the College of Natural Science.
An explanation for what happened to gas giants in other solar systems and ours was published in the journal Nature.
It is a nice model.
Clouds of gas and dust give birth to stars. The early solar system was filled with a primordial disk of gas that played an important role in the formation and evolution of the planets.
Scientists believed that the gas giants initially circled the sun in a neat, compact, evenly-spaced pattern. Jupiter, Saturn, and the others have settled into oblong, askew and spread out circles.
The question for researchers now is why.
An international team of scientists proposed an answer to that question in 2005. The solution was developed in Nice, France. There was an instability among these planets, and a chaotic set of interactions that set them on their current paths.
This was a shift in how people thought about the solar system.
Over the past 17 years, scientists have found new questions to ask about what causes the Nice model instability.
The dispersal of the primordial gas disk that spawned the solar system was thought to have caused the gas giant instability. Some of the moon rocks retrieved by the Apollo missions suggest it happened more quickly. That raises questions about how the interior solar system evolved.
Working with Sean Raymond from the University of Bordeaux in France, as well as with other people, Jacobson was able to find a fix for how the instability started. The team has a proposal.
I think our new idea could really relax a lot of tensions in the field because what we've proposed is a very natural answer to when the giant planet instability occurred.
There is a new Trigger.
Raymond and Jacobsen had a conversation in 2019. The gas giants may have been set on their current paths because of how the primordial gas disk evaporated. That could explain how the planets spread out earlier in the solar system than the Nice model would have you believe.
Raymond wondered if the Nice model was necessary to explain the solar system.
Raymond and Jacobsen reached out to the man who pioneered the idea of a rebound effect through simulations of gas disks and large exoplanets in other solar systems.
The situation in our solar system is slightly different because Jupiter, Saturn, Uranus and Neptune are distributed on a different path.
Raymond said that the team found that the Nice model instability was caused by the inside-out dissipation.
He said that they strengthened the Nice model rather than destroying it.
The picture at the beginning of the instability looks the same with the new Trigger. There is a cloud of gas and dust around the sun. A group of gas giants are in a neat, compact circle around the star.
All solar systems are formed in a disk of gas and dust. As the sun turns on and starts burning its nuclear fuel, it creates sunlight, heating up the disk and blowing it away from the inside.
The cloud of gas was centered on the sun. The edge of the hole swept through each of the gas giants. The transition leads to giant planet instability with very high probability, according to the team's computer simulations. The process of shifting these large planets into their current orbits is very fast compared to the original model.
The instability occurs as the sun's gaseous disk dissipated, constrained to be within a few million years to 10 million years after the birth of the solar system.
The mixing of material from the outer solar system and the inner solar system is caused by the new Trigger. Our planet is still in the middle of forming and the Earth's geology suggests that mixing needs to happen.
The process will stir up the inner solar system and Earth can grow from that.
The team has a new explanation for what we see in our own solar system, as well as for other solar systems in our galaxy.
We are just one example of a solar system in our universe.
Planet 9 is in outer space.
The paper doesn't mention this, but it has implications for one of the most popular and heated debates about our solar system: How many planets does it have?
When the solar system had five gas giants instead of four, the Nice model worked better. According to the model, the extra planet was thrown from our solar system during the instability, which helps the gas giants find their orbits.
Caltech researchers found evidence that there may be an undiscovered planet 50 billion miles from the sun, which is 47 billion miles farther out than Neptune.
There is still no proof that a hypothetical planet named Planet X or Planet 9 actually exists. Is it possible that they could be one and the same?
The question could not be answered directly with their simulations, but they could do the next best thing. Knowing their instability Trigger correctly reproduces the current picture of our solar system, they could test whether their model works better starting with four or five gas giants.
If you start with five, you are more likely to end up with four. If you start with four, the orbits will match better.
Humans should have an answer soon. If Planet 9 is out there, the Vera Rubin Observatory should be able to spot it.
Planet 9 is controversial, so we didn't stress it in the paper, but we like to talk about it with the public.
Our solar system is still full of mysteries and discoveries that are waiting to be discovered.
More information: Beibei Liu et al, Early Solar System instability triggered by dispersal of the gaseous disk, Nature (2022). DOI: 10.1038/s41586-022-04535-1 Journal information: Nature Citation: The instability at the beginning of the solar system: Does it portend an undiscovered planet? (2022, April 27) retrieved 27 April 2022 from https://phys.org/news/2022-04-instability-solar-portend-undiscovered-planet.html This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only.
All Rights Reserved © 2024
