PLANETES is an instrument project designed to detect and characterise exoplanets. It will be installed on the European Southern Observatory’s (ESO) Very Large Telescope Interferometer (VLTI) by the end of 2028, complementing the GRAVITY instrument, in order to extend observations to shorter wavelengths, i.e. from 1 to 1.3 µm (J-band), whereas GRAVITY observes from 2 µm to 2.4 µm (K-band).
Like GRAVITY, PLANETES will rely on a photonic chip to combine and interfere the light collected by the four VLTI telescopes. As part of her PhD research, Jehanne Sarrazin is characterising several prototypes of these chips at Meudon on a dedicated test bench, in order to identify the most effective solution for the instrument.
These components are specially designed to efficiently guide infrared light. In the photo, visible light has been deliberately injected into a chip to reveal its optical guides : as these are not optimised for these wavelengths, some of the light is scattered, making their path visible.
