Simon Albrecht's research interests are in the architecture of close binary star and planet-star systems. How do these systems form and evolve over time? Do stars in binary systems acquire a common angular momentum and orientation from their parent molecular cloud? How do tidal interactions between stars, and between planets and stars, result in a redistribution of angular momentum among the rotating bodies and their orbits? Simon is further interested in the atmospheres of exoplanets and optical/infrared interferometry.
During his research he identified a close binary (DI Herculis) in which both stars are spinning on their sides relative to the orbit. This was the first clear demonstration of such a strong misalignment in a close binary system, and resolved the longstanding problem of the anomalous apsidal motion of DI Herculis. He is leading an ongoing observational program entitled BANANA (Binaries Are Not Always Neatly Aligned) project, where the orientations of stellar rotation axes are studied to constrain their formation and evolution. He also conducts similar measurements in exoplanetary systems to constrain migration theories for close-in giant planets. He finds evidence that the obliquities in these systems were initially nearly random, and that the low obliquities that are often observed are a consequence of star-planet tidal interactions.
He was part of a team, which using ground-based telescopes detected the signatures of atoms in exoplanetary atmospheres, and measured the orbital movement of an exoplanet directly. As part of his PhD research he developed a novel instrument combining high spatial and spectral resolution.