Balloon-borne Imaging of Polar Mesospheric Clouds

Abstract

Polar Mesospheric Clouds, or PMCs, are the highest forming clouds observed on Earth, forming about 80 kilometers above the polar surfaces during local summers. Due to their height, they are difficult to observe from either ground or space. In early 2013, EBEX, a balloon-borne cosmological experiment that flew over Antarctica for 11 days, serendipitously observed PMCs using its onboard star cameras. Because of the proximity of EBEX to the PMCs, and the high resolution of the star cameras, the captured images had an unprecedentedly small spatial resolution. However, the captured images also contained undesirable artifacts, such as dust spots, image gradients, and other similar pathologies. Several post-hoc techniques were developed to remedy these problems and restore the images.