Signs of late infall and possible planet formation around DRTau using VLT/SPHERE and LBTI/LMIRCam

ABSTRACT This work investigates the possibility of close binary (CB) star systems having Earth-size planets within their habitable zones (HZs). First, we selected all known CB systems with confirmed planets (totaling 22 systems) to calculate the boundaries of their respective HZs. However, only eight systems had all the data necessary for the computation of HZ. Then, we numerically explored the stability within HZs for each one of the eight systems using test particles. From the results, we selected five systems that have stable regions inside HZs, namely Kepler-34,35,38,413, and 453. For these five cases of systems with stable regions in HZ, we perform a series of numerical simulations for planet formation considering discs composed of planetary embryos and planetesimals, with two distinct density profiles, in addition to the stars and host planets of each system. We found that in the case of the Kepler-34 and 453 systems, no Earth-size planet is formed within HZs. Although planets with Earth-like masses were formed in Kepler-453, they were outside HZ. In contrast, for the Kepler-35 and 38 systems, the results showed that potentially habitable planets are formed in all simulations. In the case of the Kepler-413system, in just one simulation, a terrestrial planet was formed within HZ.

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Machine learning applied to simulations of collisions between rotating, differentiated planets

Computational Astrophysics and Cosmology ◽

10.1186/s40668-020-00034-6 ◽

2020 ◽

Vol 7 (1) ◽

Author(s):

Miles L. Timpe ◽

Maria Han Veiga ◽

Mischa Knabenhans ◽

Joachim Stadel ◽

Stefano Marelli

Keyword(s):

Machine Learning ◽

Planet Formation ◽

Critical Role ◽

Ensemble Methods ◽

Terrestrial Planet ◽

Data Driven ◽

Analytic Methods ◽

Accurate Treatment ◽

Post Impact ◽

The Cost

AbstractIn the late stages of terrestrial planet formation, pairwise collisions between planetary-sized bodies act as the fundamental agent of planet growth. These collisions can lead to either growth or disruption of the bodies involved and are largely responsible for shaping the final characteristics of the planets. Despite their critical role in planet formation, an accurate treatment of collisions has yet to be realized. While semi-analytic methods have been proposed, they remain limited to a narrow set of post-impact properties and have only achieved relatively low accuracies. However, the rise of machine learning and access to increased computing power have enabled novel data-driven approaches. In this work, we show that data-driven emulation techniques are capable of classifying and predicting the outcome of collisions with high accuracy and are generalizable to any quantifiable post-impact quantity. In particular, we focus on the dataset requirements, training pipeline, and classification and regression performance for four distinct data-driven techniques from machine learning (ensemble methods and neural networks) and uncertainty quantification (Gaussian processes and polynomial chaos expansion). We compare these methods to existing analytic and semi-analytic methods. Such data-driven emulators are poised to replace the methods currently used in N-body simulations, while avoiding the cost of direct simulation. This work is based on a new set of 14,856 SPH simulations of pairwise collisions between rotating, differentiated bodies at all possible mutual orientations.

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Can D-D fusion contribute to Jupiter's excess heat?

Symposium - International Astronomical Union ◽

10.1017/s0074180900218068 ◽

2004 ◽

Vol 202 ◽

pp. 280-282

Author(s):

Rachid Ouyed

Keyword(s):

Planet Formation ◽

Internal Heating ◽

Excess Heat ◽

Heating Source ◽

General Aspects

We explore the highly speculative idea of Deuterium - Deuterium (D-D) fusion inside Jupiter as an internal heating source. We suggest that D could have been brought deep inside the planet by planetesimals (during the process of planet formation) and deposited through planetesimal/ices vaporization. Here, the general aspects of the model are presented.

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Interaction of solid bodies with atmospheres of protoplanets

Proceedings of the International Astronomical Union ◽

10.1017/s1743921319001996 ◽

2018 ◽

Vol 14 (S345) ◽

pp. 351-352

Author(s):

Ernst A. Dorfi ◽

Florian Ragossnig

Keyword(s):

Kinetic Energy ◽

Physical Properties ◽

Planet Formation ◽

Frictional Heating ◽

Protoplanetary Disk ◽

Small Bodies ◽

Early Stages ◽

Break Up ◽

Solid Bodies ◽

Stellar Source

AbstractDuring the early stages of planet formation accretion of small bodies add mass to the planet and deposit their energy kinetic energy. Caused by frictional heating and/or large stagnation pressures within the dense and extended atmospheres most of the in-falling bodies get destroyed by melting or break-up before they impact on the planet’s surface. The energy is added to the atmospheric layers rather than heating the planet directly. These processes can significantly alter the physical properties of protoplanets before they are exposed with their primordial atmospheres to the early stellar source when the protoplanetary disk becomes evaporated.

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