Technology development in UV coronagraphy to enable characterization of Earth-like exoplanets

NASA's Habitable Worlds Observatory (HWO) concept and the 2020 Decadal Survey's recommendation to develop a large space telescope to "detect and characterize Earth-like extrasolar planets" requires new starlight suppression technologies to probe a variety of biomarkers across multiple wavelengths. Oxygen abundance in an exoplanet atmosphere is one of the key ensembles of features which suggest biological activity and constrains the evolutionary stage of an Earth-like planet atmosphere (Archean, Protozoic, or Modern Earth). On Earth-like planets, ozone generated by a combination of photolysed atomic oxygen with molecular oxygen is unlikely to persist without a biological source when accompanied by methane (CH4). Broadband absorption due to ozone is a dramatic signal, starting shortward of 350 nm and peaking below 300 nm, which can be detected with low spectral resolution. Longer blue and violet light also probes Rayleigh scattering effects, constraining atmospheric mean molecular mass. Despite the high value of direct ultraviolet (UV) exoplanet observations, high-contrast coronagraph demonstrations have yet to be performed in the UV. The shortest wavelength probed by the Roman Coronagraph technology demonstration mission is 545 nm, and current high contrast imaging testbeds probe a similar (or longer) wavelength regime, leaving a considerable technology gap at shorter wavelengths. Typical coronagraph leakage sources such as wavefront error, surface scatter, polarization aberrations, and coronagraph mask quality all become more significant in the UV and threaten the viability of HWO to produce meaningful science in this vital regime. Establishing the technological feasibility of measuring UV ozone absorption as a means of characterizing Earth-like planets is thus a key step to designing the HWO. This proposal seeks to lay the groundwork for such a design by developing detailed contrast budgets for UV coronagraphy and validating them in a vacuum environment. The results will be used to guide the development of optical requirements for HWO to enable its science goals. The University of Arizona has developed a vacuum high-contrast testbed, the Space Coronagraph Optical Bench (SCoOB) with UV-compatible optics that eliminates atmospheric turbulence and has reached below 5e-9 monochromatic raw contrasts at 633 nm. To disentangle wavelength- and polarization-dependent effects, experiments in multiple coronagraph architectures will be tested over a range of wavelengths from 200 to 500 nm. We will also conduct component level testing of the coronagraph optics using high-resolution surface roughness metrology, scattered light measurements, and Mueller matrix spectropolarimetry to validate coronagraph optical models that predict leakage owing to surface scatter and polarization aberrations. Additionally, we propose to suggest requirements for high-contrast imaging and polarimetry, including additional exoplanet science cases in blue and UV wavelengths, such as Rayleigh scattering in extrasolar terrestrial and gas giant atmospheres and excess UV emission generated from actively-accreting protoplanets, to better understand the scientific yield of high-contrast observations as a function of UV wavelength coverage.

This is a mature technology (TRL 7+) — the realistic path in is usually NASA's Technology Transfer Program: licensing an existing NASA patent, or a Space Act Agreement to use NASA facilities/expertise directly. NASA also runs a startup licensing program with no upfront fee for companies formed to commercialize a specific NASA technology.

None of these are guaranteed paths for this specific project — TechPort itself doesn't have an "apply" button. Reaching out to the contact(s) above with a specific question is usually the fastest way to find out what's actually open.