AKATSUKI-IR2 reveals unexpected opacity disruption affecting Venus's lower clouds every 9 days

The images of AKATSUKI acquired with the camera IR2 at 1.74-2.3 µm report the discovery of an equatorial disruption or “front” in the opacity of the lower clouds of Venus at 50 km between 30ºN¿30ºS. This feature appears on the night every 9 terrestrial days during more than 8 months, and introduces a dramatic and abrupt increase of the cloud opacity and reducing the thermal radiance in a factor of about 1:2 from its brightest to the darkest side.Peer ReviewedPostprint (published version