We’re starting to see some come through for the Extremely Large Telescope (ELT), which hopefully will get a more imaginative name when the 39m behemoth is officially commissioned in Chile in the 2030s. To detect those lines, the ELT will use a specially designed instrument known as the ArmazoNes high Dispersion Echelle Spectrograph (ANDES), and previously known as HIRES. As one of the main instruments on the ELT, ANDES will be responsible for capturing the light from these planets as they transit in front of their star. It would take roughly four times as many transits to detect oxygen as it would to detect water. Learn More:E. Kurzawa-Ferrandez, A. Bello-Arufe, R. Hu - Biosignature detectability on transiting habitable worlds with ELT/ANDESUT - Life Beyond Biosignatures: A New Method In The Search For LifeUT - Forget Searching for Individual Biosignatures.