The Nautilus Array will consist of approximate one hundred identical unit telescopes. The unit telescopes are all light-weight with a single, non-cooled instrument, a visual/near-infrared spectrograph, located at the geometric center of the spherical spacecraft.
Launch and deployment: The unit telescopes are launched in a compact format and deployed in orbit. Fundamentally, each unit telescope consists of three components: the lightweight MOD-EnMat lens, the instrument package, and an inflatable spherical mylar balloon. With the balloon deflated the unit telescopes are approximately 1m x 5m cylinders; in orbit the inflation of the balloon deploys the sunshield and moves the instrument packages into the focal plane. Depending on the launch vehicle more than a dozen Nautilus units can be launched simultaneously.
Operations: The Nautilus Unit operates in two modes: the survey mode, in which it will carry out the most comprehensive exoplanet transit search to date; and the atmospheric analysis mode, in which it will perform the most detailed studies of atmospheric composition and climate diversity in earth-like exoplanets.
Survey mode: The unit telescopes carry out a sensitive exoplanet transit search by independently monitoring up to one hundred target fields, each with a light-collecting power four times greater than that of the Hubble Space Telescope and about twenty five times greater than the Kepler mission. The unit telescopes will be able to detect the transits of earth-sized planets around sun-like stars over galactic scales (up to about 10 kpc or about 33,000 light years).
Atmospheric Analysis Mode: During known transit events all unit telescopes will target the same star. Each telescope will be able to individually measure minute changes in the starlight as it filters through the planet’s atmosphere. Several key components of planetary atmospheres have prominent signatures in transmitted light – by measuring the depths of the exoplanet transits at different wavelengths we can explore what gases are present in the atmosphere. The data from the individual Nautilus telescopes can combined (digitally co-added), creating a light gathering power and data quality equivalent to those of a 50m space telescope.
The Nautilus array is optimized to detect atmospheric components that emerge from biological processes or can test the habitability of the targeted planets: for example, with its wavelength coverage of 0.5-1.6 microns the Nautilus array will be capable of detecting molecular oxygen (O2), ozone (O3), and water (H2O).