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Science measurements and instruments for a planetary science stratospheric balloon platform

Balloon platforms operating in Earth's upper stratosphere offer a unique platform to conduct new, high value planetary science observations of our solar system and exoplanets. There are compelling science drivers for conducting observations from such a balloon platform, with several potential high value science measurements that can be accomplished with one of several instrument concepts. Observations from 100,000 to 120,000 feet, which can last from hours to months, night and day, offer significant advantages over observations from ground and aircraft platforms. The stability of the airmass at float altitude is indistinguishable from space so that diffraction-limited performance can be obtained without adaptive optics, resulting in performance at visible wavelengths better than many ground based assets with larger apertures. With >99% of the atmosphere, and almost all the telluric water and CO2, beneath the platform, previously obscured spectral windows are also now open (e.g. water, CO2, and the organic fingerprint region of 5-8 μm), others are now fully free from telluric contributions, and observations in the mid through thermal infrared (IR), as well as shortward into the near ultraviolet (NUV), experience more than an order of magnitude less downwelling radiance than do ground based measurements enabling longer integration times and higher contrast observations. Instrument types that would support high value science include broadband and multispectral high spatial resolution NUV-NIR imagers, multispectral and hyper spectral imagers in the 2.5-5 μm range, as well as in the 5-8 μm range.