Calendar

Speaker: A. Garrido (UNIPA)

Titolo: Analysis of exoplanetary atmospheres.

Abstract:

Speaker:  Darius Modirrousta Galian

Titolo: Theoretical exoplanetology

Seminario: Why does 55 Cancri e have a H/H 2 -rich atmosphere? Why is there a bimodal distribution of exoplanet radii with one peak at ~ 1.3R ⨁ , the other and ~ 2.4R ⨁ , and the minima at ~ 1.8R ⨁ .
Why do some airless magma ocean super-Earths have albedos close to ~ 50% when earth-based magmas have measured albedos of ~ 10%? Conversely, why are some hot Jupiters so dark with albedos of ~ 1% or below? New data from astronomical measurements shows that
the universe is far more complex and interesting than what traditional literature predicted. Understanding these bodies and phenomena is not a trivial task, but by coupling different scientific fields with observational data it may be possible to shed some light on these systems.

Speaker:  Ruggero Biondo

Titolo: Data-driven Numerical Reconstruction of the Interplanetary Parker Spiral

Abstract: Over the last decade the science community, governments and private partners have shown a growing interest in the topic of Space Weather: a broad discipline aimed to the forecasting of potential threats to space and ground-based systems and operations. The ability of the state-of-art codes to reconstruct the stationary conditions of the interplanetary plasma is still limited, as shown by the comparisons between model predictions and in-situ measurements acquired by various spacecrafts. Therefore, it is necessary to develop leaner codes and to improve the agreement between forecasts and observed data on the other. The aim of this work is to lighten the procedures involved in determining the inner heliospheric boundary and to bind the numerical simulations to direct measurements of the parameters of the interplanetary plasma. To do this, the ambient plasma parameters of the inner heliosphere are reconstructed, using the 1 AU data provided by the Solar Physics Group in INAF-Turin Astrophysical Observatory from different spacecrafts located in the lagrangian point L1 such as DSCOVR and GGS Wind, by going backwards to 0.1 AU following the spiraling arms of the Interplanetary Parker Spiral. The back-reconstructed plasma parameter at 0.1 AU are thus employed as inner boundary conditions for the solar wind expansion up to 1 AU based on a MHD simulation. This innovative approach provides a new method to reconstruct the conditions of the interplanetary plasma from the Sun to 1 AU and beyond