The Nice model is a widely-accepted hypothesis in planetary science that describes the dynamical evolution of the outer Solar System. It was first proposed in 2005 by a team of astronomers, including Alessandro Morbidelli, Rodney Gomes, Kleomenis Tsiganis, and Harold F. Levison, and is named after the city of Nice, France, where much of the research was conducted. The model provides a framework for understanding the formation and migration of the gas giants and the resulting impact on the Solar System's smaller bodies, such as asteroids, comets, and Kuiper Belt objects.[1]
Overview[]
The Nice model suggests that the giant planets of the Solar System—Jupiter, Saturn, Uranus, and Neptune—formed in a more compact configuration than their current positions. Over time, interactions between the planets and a primordial disk of planetesimals (small solid bodies) led to the outward migration of Uranus and Neptune and the inward migration of Jupiter. These movements caused significant disruptions in the planetesimal disk, scattering its contents across the Solar System and beyond.[2]
Key Features of the Model[]
- Planetary Migration: The Nice model proposes that gravitational interactions between the planets and the planetesimal disk resulted in the gas giants migrating from their initial positions. Jupiter moved inward slightly, while Saturn, Uranus, and Neptune migrated outward.[3]
- Late Heavy Bombardment (LHB): The destabilization of the planetesimal disk is thought to have caused the Late Heavy Bombardment, a period approximately 4 billion years ago when a high number of asteroids and comets bombarded the inner Solar System, creating the large craters still visible on the Moon and other planetary bodies.[4]
- Resonance Crossing: As Jupiter and Saturn migrated, they crossed a 2:1 mean-motion resonance, meaning Jupiter completed two orbits for every one orbit of Saturn. This resonance crossing is a critical event in the Nice model, as it triggered a chaotic reorganization of the outer planets and the scattering of the planetesimal disk.[5]
- Kuiper belt and Oort cloud Formation: The scattering of planetesimals by Uranus and Neptune explains the current structure of the Kuiper belt and the formation of the distant Oort cloud, which contains icy bodies on the Solar System's periphery.[6]
Variations and Updates[]
Subsequent studies have refined the Nice model to address observations and challenges. One such variation, known as the Jumping-Jupiter scenario, suggests that Jupiter’s interactions with a hypothetical additional ice giant could explain certain anomalies in the orbital structure of the inner and outer Solar System.[7]
Advancements in computer simulations and observational astronomy have further tested and supported the Nice model, while also raising questions about the initial conditions required for the model to work. For instance, the model assumes a massive and dynamically cold planetesimal disk, a condition that aligns with current theories of Solar System formation but remains a topic of investigation.[8]
Implications[]
The Nice model has significantly influenced our understanding of planetary formation and migration. It has provided insights into:
- The distribution of small bodies in the Solar System, including the Kuiper belt, Scattered Disc, and Oort cloud.[9]
- The cratering history of terrestrial planets and moons, particularly during the Late Heavy Bombardment.[9]
- The migration histories of exoplanetary systems, where similar planetary movements have been observed.[10]
Criticisms and Challenges[]
While widely regarded as a robust explanation for the dynamics of the early Solar System, the Nice model faces several challenges:
- Timing of the Late Heavy Bombardment: Some studies question whether the bombardment occurred as predicted by the model.[11]
- Initial Conditions: The model's reliance on specific initial configurations of planets and planetesimals has led to debates about how realistic these assumptions are.[12]
- Diversity of Exoplanetary Systems: Observations of other planetary systems raise questions about whether the Nice Model is unique to the Solar System or part of a broader framework for planetary evolution.[13]
Five-planet Nice model[]
Main Article: Five-planet Nice model
The Five-planet Nice model is a refinement of the Nice model, a hypothesis describing the early dynamical evolution of the Solar System. This version of the model includes an additional ice giant, suggesting that the early Solar System contained five giant planets instead of the four currently observed—Jupiter, Saturn, Uranus, and Neptune. According to this model, the fifth planet was ejected from the Solar System during a period of planetary migration and gravitational interactions roughly 600 million years after the Solar System's formation. These interactions, triggered by the dissipation of the protoplanetary disk and interactions with a primordial disk of planetesimals, are thought to have caused the current orbital configurations of the giant planets and the Late Heavy Bombardment of the inner Solar System. The model explains the highly eccentric and inclined orbits of some trans-Neptunian objects and provides a plausible mechanism for the existence of a population of rogue planets in interstellar space.[14][15]
References[]
- ↑ http://docmadhattan.fieldofscience.com/2011/05/nice-model-of-solar-system.html#:~:text=In%20conclusion:%20the%20Nice%20model,strong%20evidence%20for%20their%20model.
- ↑ https://www.aanda.org/articles/aa/full_html/2011/08/aa15731-10/aa15731-10.html#:~:text=The%20planetesimals%20conforming%20this%20disk%20gravitationally%20interact,to%20undergo%20a%20phase%20of%20dynamical%20instability.
- ↑ https://lucy.swri.edu/2018/04/24/Nice-Model.html#:~:text=The%20planets%20interacted%20with%20each%20other%20and,that%20was%20ejected%20from%20the%20Solar%20System!)
- ↑ https://science.nasa.gov/moon/lunar-craters/what-is-the-late-heavy-bombardment/#:~:text=That's%20the%20theory%20of%20the%20Late%20Heavy,system's%20formation%20crashing%20into%20the%20inner%20planets.
- ↑ https://link.springer.com/10.1007/978-3-642-11274-4_1058#:~:text=Definition.%20The%20so%2Dcalled%20Nice%20model%20is%20a,role%20in%20shaping%20the%20present%2Dday%20Solar%20System.
- ↑ https://science.nasa.gov/solar-system/oort-cloud/facts/#:~:text=In%20short%2C%20gravity%20from%20the%20planets%20shoved,what%20we%20now%20call%20the%20Oort%20Cloud.
- ↑ https://www.calacademy.org/explore-science/jumping-jupiter-batman
- ↑ https://www.aanda.org/articles/aa/full_html/2011/08/aa15731-10/aa15731-10.html#:~:text=Batygin%20&%20Brown%20(2010)%20extended%20this%20work,not%20exactly%20the%20same%20as%20those%20proposed
- ↑ 9.0 9.1 https://nap.nationalacademies.org/read/26714/chapter/4
- ↑ https://arxiv.org/html/2404.14982v1
- ↑ https://www.boulder.swri.edu/~bottke/Reprints/Bottke_Norman_2017_AnnuRev-Earth-Planet_45_619_Late_Heavy_Bombardment.pdf
- ↑ https://www.aanda.org/articles/aa/full_html/2011/02/aa15277-10/aa15277-10.html#:~:text=This%20argues%20that%2C%20even%20if%20giant%20planet,between%20Jupiter%20and%20a%20third%2C%20Neptune%2Dmass%20planet.
- ↑ https://www.sciencedirect.com/topics/physics-and-astronomy/planet-formation#:~:text=Although%20a%20comprehensive%20theory%20of%20planet%20formation,suggest%20that%20planet%20formation%20takes%20place%20readily.&text=Moreover%2C%20simulations%20of%20the%20Nice%20model%20(Tsiganis,from%20radially%20migrating%20beyond%20its%20current%20orbit.
- ↑ https://lucy.swri.edu/2018/04/24/Nice-Model.html#:~:text=It%20postulates%20that%20when%20the,us%20to%20test%20these%20ideas.
- ↑ http://link.springer.com/10.1007/978-3-662-44185-5_1058#:~:text=Definition.%20The%20so%2Dcalled%20%E2%80%9CNice%20model%E2%80%9D%20describes%20dynamical,role%20in%20shaping%20the%20present%2Dday%20Solar%20System.
| Models of the Solar System | ||
|---|---|---|
| Solar Formation | Nebular hypothesis | |
| Dynamical Evolution | ||
| Origin of the Moon | ||
| Early Development | Grand tack hypothesis • Fission theory • Co-formation theory • Capture theory • Migration of Neptune • Jumping-Jupiter scenario | |
| Later Development | Nice model (Nice 2 model • Five-planet Nice model) | |
| Planetary Formation | Giant-impact hypothesis | |
| Placement | Heliocentric model • Geocentric model | |