Searching for Earth 2.0 -- a practical approach
Sagi Ben-Ami
Smithsonian Astrophysical Institute

Building a compelling case for the detection of true Earth analogs requires an extremely large telescope and a high-resolution spectrograph working in tandem to characterize the planets' masses and search for bio-signatures in their atmospheres. The upcoming Giant Magellan Telescope (GMT) -- and its first-light instrument, the GMT- Consortium Large Earth Finder (G-CLEF) -- will be uniquely positioned to enable the discovery of Earth-like planets in the next decade. Following their discovery, however, the detection of molecular oxygen (O2) in their atmospheres is crucial in deeming them true Earth analogs. In a detailed study aimed at maximizing the likelihood of detecting O2 in an Earth-like exoplanet atmosphere my colleagues and I found that the optimal spectral resolution for detection is upwards of, significantly higher than those achieved by modern high resolution spectrographs on large telescopes. To address the instrumental challenges of achieving these extreme high resolutions, I have designed FIOS -- a Fabry Perot based Instrument for Oxygen Searches, a unique instrument designed from the ground up for O2 detection through transmission spectroscopy. My talk is structured as follows: I will begin with an overview of G-CLEF's design and science capabilities, followed by a discussion on the unique challenges associated with O2 detection in the atmospheres of terrestrial exoplanets. I will then discuss the physical principles behind FIOS, and demonstrate the advantages of such an instrument via comprehensive MC simulations. I will conclude by describing the current state of the FIOS prototype currently assembled at the CfA labs.