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About the talk:

Most of Astronomy is based on measurements of the intensity of the light from celestial bodies. For instance, from the subtle variability of the light of a star we can deduce the presence of a planet around it; stellar spectra can reveal the composition of a star, and those of distant galaxies can tell us how fast the Universe is expanding. However, the light is characterised not only by its intensity, but also by the way in which it propagates itself, a feature that we call ‘polarisation’. The instruments that we use to measure polarisation have optical elements that resemble very much to the lenses of Polaroid sunglasses. Polarised light carries a somewhat hidden information about the nature of the object that we are observing. Polarimetric techniques are routinely used in Astronomy to reveal the presence of a magnetic field in the atmosphere of a star, to measure the size of asteroids, or to find the composition of cometary dust. I will explain how polarimetric techniques are used in everyday’s life, and how they have made it possible, recently, to see how magnetic white dwarfs funnel debris of their planetary systems into their atmosphere, and to find life on Earth (!)

About Dr. Bagnulo:

Stefano Bagnulo obtained his PhD at QUB in Belfast in1996, and since then has worked at the University of Vienna and then at the Paranal Observatory in Chile, where he was a member of the Science Operations Team of the ESO Very Large Telescope. He joined Armagh Observatory in 2007.

Click this link to read about his work at AOP