MAssivE STaR Outflow: Far-UV HST data to analyze the massive star winds (MAESTRO-UV). (MAESTRO-UV)

Massive stars are key components of galaxies. Characterized by high luminosities and strong outflows, their evolution is strongly impacted by the amount of mass and angular momentum lost through stellar winds. While previously deemed smooth and spherically symmetric, the outflows of massive stars are now found to be inhomogeneous, i.e. clumpy. This severely hampers earlier estimates of the mass-loss rates of hot massive stars and the validity of mass-loss recipes widely adopted in stellar evolution and population synthesis computations.

In this context, the MAESTRO (MAssivE StaR Outflows) project aims to achieve a comprehensive analysis of the wind structure by combining ultraviolet and optical observational diagnostics and a new generation of stellar wind models capable of a detailed treatment of clumping structure (including porosity and vorosity).