Special Seminar

The Path to Characterizing Earth-like Exoplanets with High Contrast Spectroscopy

Characterizing the atmospheres of Earth-like exoplanets requires spectroscopy of R ~ 100-1000 at extreme contrasts (~1e-7–1e-10), small angular separations  (~1–5 λ/D), and over long integration times from space with missions such as the Habitable Worlds Observatory (HWO).  In this regime, spectroscopic performance is limited by photon efficiency, stability, and the need to control and calibrate residual starlight with extreme precision.

In this talk, I describe the technological path to obtaining spectra of exo-Earths from my work on laboratory-based advances and current 8-10m class ground-based telescopes.  I describe my leading, recent role in the development and commissioning of HiRISE on VLT, an instrument designed to characterize young giant exoplanets at high spectral resolution by coupling a high-contrast imager with a high-resolution spectrograph through a single-mode fiber (SMF).

I am spearheading the next breakthrough in high-contrast spectroscopic technology development with astrophotonics.   I describe upcoming, on-sky tests of two key astrophotonics advances at the Subaru Telescope – the photonic lantern (PL) and the thermal phase shifting photonic integrated circuit (PIC) – and the parallel maturing of these technologies in the laboratory whose development I led at UTSA.

Finally, I discuss potential applications of astrophotonics for characterizing gas giant to rocky planet atmospheres with the UT Austin funded-Giant Magellan Telescope and Earth twins with HWO.  Throughout, I describe the major scientific advances enabled by spectroscopy with SMFs and astrophotonics as well as the role that complementary McDonald Observatory instrumentation can play in maximizing the science return of these efforts.