Water masers and the death of stars
Stars similar to our Sun undergo radical changes as their lives draw to an end. After swelling up to huge red giants, they start to pulsate, blowing off large clouds of gas and dust, to create intricately shaped and mesmerizing planetary nebulae. The remaining part of the star collapses under gravity, creating a compact white dwarf to slowly cool and fade away. One of the pivotal questions in this evolutionary scenario is how to explain the shapes of planetary nebulae, whose morphology depart significantly from spherical symmetry. Fortunately, we can use VLBI observations of water masers to get some insight into the last throes of dying stars by tracing their powerful molecular jets forming and shaping their environments. In my talk I will show results from such VLBI observations to get an idea on how stars like our Sun behave when they finally die.