Descrizione del progetto
Uno studio sull’evaporazione dell’atmosfera planetaria getta luce sulla formazione di un pianeta
Nonostante il progresso della ricerca, resta limitata la comprensione dei processi che portano alla formazione di un pianeta. Molti esopianeti, ovvero pianeti che orbitano attorno a stelle diverse dal Sole, hanno atmosfere volatili. La stretta vicinanza alle stelle rende le atmosfere superiori degli esopianeti vulnerabili alla perdita di massa, attraverso l’evaporazione causata dal riscaldamento. I partner del progetto PEVAP hanno recentemente svolto un ruolo decisivo stabilendo che l’evaporazione delle atmosfere planetarie provoca l’evoluzione della popolazione osservata dell’esopianeta. Questo sviluppo della ricerca sottolinea l’importanza della comprensione dell’evaporazione per decifrare la formazione di un esopianeta. L’obiettivo del progetto PEVAP, finanziato dall’UE, è di creare i primi modelli al mondo esaustivi sull’evaporazione esoplanetaria. Fornendo risposte alle domande cruciali sui processi e gli effetti dell’evaporazione, il team del progetto PEVAP aiuterà a spiegare come sono nati gli esopianeti.
Obiettivo
Modern astronomy has truly entered the exoplanet era. Although our knowledge of what planet formation produces has grown immensely thanks to observational advances, our actual understanding of the physical processes that give rise to planets and planetary systems is limited. We now know most stars are unlike our own Sun, in that they host planets which orbit around their star with periods of months or shorter, yet many have volatile rich atmospheres. These planets must result from a dominant (if not the dominant) mode of planet formation, yet they were completely missing from our planet formation theories a decade ago.
Planets which are close to their parent star are extremely vulnerable to mass-loss through evaporation, where UV/X-ray photons can heat their upper atmospheres to close to the escape temperature, causing them to lose-mass. Recently, I have played a leading role in showing that evaporation drives the evolution of the observed exoplanet population. Thus, the observed exoplanet population is not representative of the one at birth; to use it as a probe of planet formation we must understand evaporation. However, the evaporation of highly-irradiated planetary atmospheres is not well understood. This especially true for terrestrial planets where the atmospheres are dominated by heavy elements.
My team will use a combination of theory, simulations and observations to build the first global and comprehensive models of exoplanet evaporation. In doing this, my team will use evaporation as a window into planet formation by answering the following key questions:
1 What are the mass-loss rates and evaporative flow structures for the full spectrum of observed planets?
2 How can we use observations of evaporating planets to learn about their compositions and histories?
3 How does evaporation affect and control the evolution of planets and their atmospheres?
By understanding how exoplanets evaporate and evolve, my team will unveil the exoplanet population at birth.
Campo scientifico
Parole chiave
Programma(i)
Argomento(i)
Meccanismo di finanziamento
ERC-STG - Starting GrantIstituzione ospitante
SW7 2AZ LONDON
Regno Unito