Ground-based telescopes can be much larger than telescopes launched into space, allowing enhanced sensitivity and resolution for the study of exoplanets or other astronomical objects with compact sizes or separations. Adaptive optics have been developed for ground-based telescopes to overcome the blurring of images due to turbulence in the Earth's atmosphere, and allow the full potential of large apertures to be realized. Adaptive optics at visible wavelengths now out-performs the Hubble Space Telescope (in terms of angular resolution), and near-IR adaptive optics systems on other Arizona telescopes provide some of the highest resolution images available. Combining adaptive optics and interferometry allows even larger, more powerful telescopes. Arizona’s Large Binocular Telescope Interferometer (LBTI) provides the angular resolution of a 23-m telescope, thus functioning now as the first of the “Extremely Large Telescopes.”

Many fields of research in astronomy depend critically on observations with high angular resolution. Researchers at Arizona often focus on exoplanets and their natal environments, using adaptive optics and interferometry to better understand formation pathways of planets and the demographics of mature planetary systems. A range of other topics are also studied, including white dwarfs, brown dwarfs, and active galactic nuclei. Steward Observatory astronomers also actively pursue the development of new instrumentation and techniques to push towards extremely high resolution and contrast (extreme AO), and also uniquely low background, high-sensitivity infrared observations with adaptive secondary mirrors.