Conor A Nixon¹, M Cordiner¹, Alexander E Thelen¹, Zbigniew Kisiel², Nicholas A Teanby³, Patrick GJ Irwin⁴, Steven B Charnley¹ and Yi-Jehng Kuan⁵, (1)NASA Goddard Space Flight Center, Greenbelt, MD, United States, (2)Polish Academy of Sciences, Institute of Physics, Warsaw, Poland, (3)University of Bristol, Bristol, United Kingdom, (4)University of Oxford, Oxford, United Kingdom, (5)National Taiwan Normal University, Taipei, Taiwan