In the realm of low-viscosity protoplanetary discs (PPDs), our understanding of the formation of the Solar System is being challenged. Recent studies have shown that the Jupiter-Saturn pair, while migrating inwards, becomes locked in the 2:1 mean motion resonance, rendering the popular Grand Tack scenario impossible.
To shed light on the potential formation scenarios of the Solar System in low-viscosity discs, we embarked on a series of hydrodynamical simulations. Our aim was to investigate the migration patterns of giant planets within a disc with a viscosity of α=10−4.
Upon entering a gas-less phase, we thoroughly examined the stability of various resonant chains formed by multiple giant planets. To do so, we observed their interactions with leftover planetesimals by conducting N-body simulations using the rebound software. Notably, in discs with lower viscosity, the gaps created by the giant planets were wider and deeper, resulting in reduced damping effects and weaker resonant chains.
Through this extensive exploration, we stumbled upon five stable resonant chains consisting of four or five planets. Intriguingly, in thin PPDs, these chains showcased a unique migration behavior – the four giant planets reversed their migration and began moving outwards. Following the dispersal of the gas disc, these resonant chains continued their migration over a billion years, influenced by a belt of planetesimals.
It is worth noting that while some of these resonant chains experienced an instability phase, others migrated smoothly. Ultimately, approximately 1% of the final configurations of three of these resonant chains resembled the orbital parameters of the giant planets in our very own Solar System.
This exciting discovery opens up new avenues for understanding the formation and evolution of planetary systems. The significance of low-viscosity protoplanetary discs in shaping the dynamics of giant planets cannot be understated, and further research will undoubtedly reveal additional insights into the fascinating origins of our celestial neighborhood.
FAQ:
1. What is the main challenge to our understanding of the formation of the Solar System in low-viscosity protoplanetary discs?
– Recent studies have shown that the popular Grand Tack scenario is rendered impossible when the Jupiter-Saturn pair becomes locked in the 2:1 mean motion resonance during their inward migration.
2. What were the aims of the hydrodynamical simulations conducted in this study?
– The aim was to investigate the migration patterns of giant planets within a low-viscosity disc and examine the stability of resonant chains formed by multiple giant planets.
3. How were the interactions between giant planets and leftover planetesimals examined?
– N-body simulations were conducted using the rebound software to observe the interactions between giant planets and leftover planetesimals.
4. What were the findings regarding the gaps created by giant planets in discs with lower viscosity?
– In discs with lower viscosity, the gaps created by giant planets were wider and deeper, resulting in reduced damping effects and weaker resonant chains.
5. What unique migration behavior was observed in thin protoplanetary discs?
– In thin protoplanetary discs, four giant planets in stable resonant chains reversed their migration and began moving outwards after the dispersal of the gas disc.
6. How long did the migration of the resonant chains continue after the dispersal of the gas disc?
– The resonant chains continued their migration over a billion years, influenced by a belt of planetesimals.
7. How many of the final configurations of the resonant chains resembled the orbital parameters of the giant planets in our Solar System?
– Approximately 1% of the final configurations of three resonant chains resembled the orbital parameters of the giant planets in our Solar System.
Definitions:
– Protoplanetary discs (PPDs): These are rotating disks of gas and dust surrounding young stars, believed to be the birthplace of planets.
– Mean motion resonance: This refers to the ratio of the orbital periods of two celestial bodies, such as planets, which causes them to have a regular repeating pattern of gravitational interactions.
– Viscosity: This refers to the resistance of a fluid to flow. In the context of protoplanetary discs, low viscosity means the fluid flows more easily.
– Gas disc: This refers to the portion of a protoplanetary disc that consists of gas.
– Planetesimals: These are small celestial bodies that are believed to be building blocks for planets.
Related links:
– Protoplanetary disk
– Mean motion resonance
– Viscosity